6 urn:lsid:arphahub.com:pub:DE333E49-E4EE-5693-9BEF-D446E6301C98 urn:lsid:zoobank.org:pub:55528528-5C97-4D79-A718-8B3D153B37CC Journal of Hymenoptera Research JHR 1070-9428 1314-2607 Pensoft Publishers 10.3897/jhr.99.190905 190905 Research Article Ichneumonidae Ichneumonoidea Biogeography Faunistics & Distribution General ecology Identification key Systematics Taxonomy Terrestrial Tropical Forests Cenozoic Neogene Africa Central America South America Local diversity of Afrotropical and Neotropical Brachycyrtinae (Hymenoptera, Ichneumonidae), with two new species from western Amazonia and keys to species Österman Emil M. emil.m.osterman@gmail.com https://orcid.org/0009-0008-8307-5804 1 Conceptualization Writing - original draft Writing - review and editing Investigation Project administration Hopkins Tapani https://orcid.org/0000-0002-2256-0098 1 Conceptualization Writing - original draft Writing - review and editing Data curation Funding acquisition Investigation Resources Visualization Kaunisto Kari M. https://orcid.org/0000-0001-6665-0047 1 Writing - review and editing Visualization Gómez Isrrael C. https://orcid.org/0009-0007-1752-8046 1 Writing - review and editing Investigation Österman Iida A. E. https://orcid.org/0009-0002-9532-1060 2 Visualization Sääksjärvi Ilari E. https://orcid.org/0000-0002-8107-5607 1 Conceptualization Writing - original draft Writing - review and editing Funding acquisition Investigation Resources Supervision Zoological Museum, Department of Biodiversity Sciences, University of Turku, Turku, Finland Zoological Museum, Department of Biodiversity Sciences, University of Turku Turku Finland https://ror.org/05vghhr25 Turku, Finland Unaffiliated Turku Finland

Corresponding author: Emil M. Österman (emil.m.osterman@gmail.com)

Academic editor: Tamara Spasojevic

 2026 01 09 2026 99 955 993 3C44FCC7-3ED1-5A98-8CC4-F36D32EBF346 68A6ECD3-3D5B-4902-AD47-77B5F8F31AA0 07 03 2026 25 08 2026 Emil M. Österman, Tapani Hopkins, Kari M. Kaunisto, Isrrael C. Gómez, Iida A. E. Österman, Ilari E. Sääksjärvi This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. https://zoobank.org/68A6ECD3-3D5B-4902-AD47-77B5F8F31AA0

Brachycyrtinae is a small subfamily of Darwin wasps (Hymenoptera, Ichneumonidae) containing one distinctive genus: Brachycyrtus Kriechbaumer, 1880. Here, we report the local diversity of brachycyrtines collected by extensive sampling in the Neotropics and Afrotropics and expand the distributional records of eleven Neotropical and one Afrotropical species. We provide identification keys and minimal diagnoses for all known Neotropical and Afrotropical species, list all known Afrotropical brachycyrtine material, and discuss the phenology, habitat use, and morphological variation of selected species. We compare the local species richness of tropical rain forest sites in Peru and Uganda. Additionally, we describe B. granulatus Österman & Sääksjärvi, sp. nov. and B. politus Österman & Sääksjärvi, sp. nov. from Ecuador and Peru, the males of B. convergens Cushman, 1936 and B. antoninoi Di Giovanni, 2021, and synonymise B. zani Gauld & Ward, 2000 (syn. nov.) with B. xorix Gauld & Ward, 2000.

 Africa Amazonia biodiversity Darwin wasp distribution Malaise trap morphological variation taxonomy Koneen Säätiö 501100005781 https://ror.org/05jwty529 http://doi.org/10.13039/501100005781 Oskar Öflunds Stiftelse 501100005763 https://ror.org/0446gjc92 http://doi.org/10.13039/501100005763 Opetus- ja Kulttuuriministeriö 501100003126 https://ror.org/02w52zt87 http://doi.org/10.13039/501100003126 Suomen Kulttuurirahasto 501100003125 https://ror.org/027xav248 http://doi.org/10.13039/501100003125 Alfred Kordelinin Säätiö 100008969 https://ror.org/0107h6s84 http://doi.org/10.13039/100008969 Suomen Akatemia 501100002341 https://ror.org/05k73zm37 http://doi.org/10.13039/501100002341 The Entomological Society of Finland, Svensk-Österbottniska samfundet, Waldemar von Frenckells stiftelse Citation

Österman EM, Hopkins T, Kaunisto KM, Gómez IC, Österman IAE, Sääksjärvi IE (2026) Local diversity of Afrotropical and Neotropical Brachycyrtinae (Hymenoptera, Ichneumonidae), with two new species from western Amazonia and keys to species. Journal of Hymenoptera Research 99: 955–993. https://doi.org/10.3897/jhr.99.190905

 Introduction

The small Darwin wasp subfamily Brachycyrtinae (Hymenoptera, Ichneumonidae) contains a single genus, Brachycyrtus Kriechbaumer, 1880, that until now included 27 species (Gauld and Ward 2000; Di Giovanni and Varga 2021; Nascimento and Fernandes 2024; Dal Pos et al. 2026). It is cosmopolitan in distribution with many species having large distributional ranges (Nascimento and Fernandes 2024; Österman et al. 2025). The species richness of currently known brachycyrtines is concentrated in the Neotropics, where nearly half of all described species have been recorded (Dal Pos et al. 2026).

Long understudied in the tropics, the taxonomy of the genus has received more attention during the past decades, leading to the description of relatively many new species from both the Neotropics and Afrotropics (Gauld and Ward 2000; Di Giovanni and Varga 2021; Nascimento and Fernandes 2024). Gauld and Ward (2000) laid the foundation for modern Neotropical brachycyrtine research by revising the Costa Rican species of the genus based mainly on material from Central America, providing descriptions of six new species and a key to ten species in the area. Nascimento and Fernandes (2024) provided a synopsis of the genus in Brazil, with the description of two new species and a key to twelve species (including all Neotropical species except for Brachycyrtus noggius Gauld & Ward, 2000). In the Afrotropics, the genus was until five years ago known from only two Malagasy specimens of different species. By examining undescribed museum specimens, Di Giovanni and Varga (2021) recorded the genus from mainland Africa for the first time and described three new species, bringing the number of known species in the Afrotropics to five (the two other species are found only in Madagascar; Seyrig 1952).

Almost all Neotropical and Afrotropical brachycyrtine taxonomy has been based on a small number of miscellaneous museum specimens (the one exception being the Costa Rican material of (Gauld and Ward 2000)). Systematic, long-term collecting has been carried out in Peru and Uganda (Sääksjärvi et al. 2004; Hopkins et al. 2019a, 2019b) but has not yet yielded results for Brachycyrtinae. Long-term collecting could provide more material for taxonomic work on brachycyrtines, since brachycyrtine species seem to have low abundances and are rarely collected.

Brachycyrtus can easily be separated from other Darwin wasps by the combination of their small size, hunched mesosoma, fore-wing vein 1cu-a being distal to M&Rs by more than half the length of 1cu-a, and their characteristic yellow-black or orange-yellow-black colouration (Broad et al. 2018). In practice, the hunched mesosoma makes them instantly recognisable, with the distal fore wing vein 1cu-a confirming an identification. Biological information is scarce for the genus, partly because they are rarely collected, although some species have been observed to be solitary parasitoids of cocooned prepupae and pupae of green lacewings (Neuroptera, Chrysopidae) (Gauld and Ward 2000). Their phylogenetic position and ovipositor morphology suggest that they are idiobiont ectoparasitoids (Short 1978; Wahl 1993).

In this article, we report the brachycyrtines collected in long-term sampling campaigns that we have carried out in western Amazonia and the Afrotropics since the late 1990s. We provide keys and brief diagnoses for all known Neotropical and Afrotropical species, provide new faunistic records, and report all known material of Afrotropical brachycyrtines. We also compare the local species richness of the genus in Amazonian and African tropical forests, discuss the phenology, habitat use, and morphological variation of selected species, recognize B. zani Gauld & Ward, 2000 as a junior synonym of B. xorix Gauld & Ward, 2000, describe the males of B. convergens Cushman, 1936 and B. antoninoi Di Giovanni, 2021, and describe two new species from Ecuadorian and Peruvian Amazonia.

 Methods Sampling

We examined material from both the Neotropics and the Afrotropics (Fig. 1). Most Neotropical Malaise trapping focused on Allpahuayo-Mishana National Reserve in Peru and most canopy fogging on Orellana in Ecuador. The sampling was less geographically extensive in the Afrotropics, where most samples are from Kibale National Park in Uganda and the rest from Mont Tonkoui in Côte d’Ivoire.

10.3897/jhr.99.190905.figure1 D18AD646-3C0B-5593-B250-4B00B897F854

Maps of the collecting localities in the Neotropics (left) and Afrotropics (right). Red circles = Malaise trapping; blue triangles = canopy fogging. Colombia: Sierra Nevada de Santa Marta (SN); Ecuador: Onkone Gare (OG), Tiputini (Ti); French Guiana: Roura (Ro), Saül (Sa); Nicaragua: Cerro Musún (CM); Peru: Allpahuayo-Mishana (A-M), Los Amigos (LA), Pakitza Rio Manu (PRM); Côte d’Ivoire: Mont Tonkoui (MT); Uganda: Kibale National Park (KNP).

https://binary.pensoft.net/fig/1762383

We conducted long-term Malaise sampling in two sites in Peruvian Amazonia: Allpahuayo-Mishana in the north and Los Amigos in the south. Allpahuayo-Mishana National Reserve (3°57–58S, 73°25–26W) is located in northern Peruvian Amazonia in the department of Loreto (Fig. 1). Los Amigos Conservation Concession (12°33–34S, 70°4–5W) is located in southern Peruvian Amazonia in the department of Madre de Dios close to the Andean-Amazonian interface (Fig. 1). The Peruvian sampling program was planned and coordinated by the last author (IES).

In Allpahuayo-Mishana, we combined material from three separate field campaigns covering three main types of non-inundated rain forest types, growing either on clayish, loamy, or white sand soils (cf. Sääksjärvi et al. (2004) and Hopkins et al. (2025)). The first campaign ran from August 1998 to January 1999 with 12 Malaise traps and the second from January 2000 to January 2001 with 15 traps. Both of these campaigns have been described in detail by Sääksjärvi et al. (2004) and Hopkins et al. (2025). The last Malaise sampling in Allpahuayo-Mishana was conducted by 14 Malaise traps, four of which were active in April–December 2011 and ten in October–December 2011. This field campaign has been described in detail by Gómez et al. (2015) and Hopkins et al. (2025). In Los Amigos, nine Malaise traps were in operation in May–July 2008 (details in Hopkins et al. 2025). The combined sampling effort of these four campaigns (three from Allpahuayo-Mishana, one from Los Amigos) was 270.2 Malaise trap months (supplementary data: Österman et al. 2026a).

In the Afrotropics, we carried out long-term Malaise sampling at one site in Uganda, Kibale National Park (0°33.750°N, 30°21.370°E; approx. 1500 m.a.s.l.). Samples were collected with 34 Malaise traps that operated for one year (2014–2015). The traps were placed in habitats that varied across a successional gradient from primary forest and swampy primary forest (swamp), through disturbed forest and clearcut former plantation, to farmland. The sampling effort totaled 382.4 trap months, of which 22.0 trap months were damaged samples or otherwise unrepresentative of a normal catch of brachycyrtines (supplementary data: Österman et al. 2026a). The study area and sampling campaign are described in greater detail in Hopkins et al. (2019a, 2019b). The Ugandan sampling was coordinated by the second author (TH).

For the taxonomic part of this study, we also included a small number of other samples collected by our collaborators: Carol Castillo in southern Peruvian Amazonia and the tropical Andes (close to Los Amigos), Terry Erwin in Ecuadorian Amazonia, the SEAG team in French Guayana, J. Castillo in Colombia, the LLAMA project in Nicaragua, and Yves Braet and Erena Dupont in Côte d’Ivoire. The Ecuadorian and Nicaraguan field work has been described in detail by Veijalainen et al. (2012, 2014).

It is important to note that all field campaigns of Allpahuayo-Mishana, Los Amigos and Kibale used exactly the same type of Malaise trap, with the size, colour, mesh size, and manufacturer all being the same, so the Malaise samples between Amazonia and Africa are comparable in that respect.

 Analyses

To compare the local species richness of our Peruvian and Ugandan sites, we modelled species accumulation rates with rarefaction curves. These allow the relative species richness of sites to be compared even when not all species have been collected, since species generally accumulate faster per individual collected where there are more species in total (cf. Gotelli and Colwell 2011). The rarefaction was based on resampling the Malaise trap samples without replacement 100 times (i.e., placing them in random order 100 times), and plotting the average number of collected species versus collected individuals of the 100 resamples. To get approximate 84% confidence intervals of these curves, we resampled the Malaise samples 100 times with replacement (i.e., the same sample could be included several times) and took the standard deviation of these curves. As a general (although approximate) rule, curves which diverge enough that their 84% confidence intervals do not overlap represent significantly (p < 0.05) different total species richnesses (Gotelli and Colwell 2011). The details of these rarefactions are described in Österman et al. (2026b).

We drew figures of the phenology and habitat use of the four species in our material which we had collected in large enough numbers to analyse (minimum of 20 specimens). Two of these species were collected in our Peruvian Malaise traps, while the remaining two were from our Ugandan Malaise traps. We performed the analyses and drew the phenology and habitat use figures in R version 4.2.1 (R Core Team 2022) with the R package ‘turkuwasps’ (v. 0.0.8) (Hopkins 2025). The data and analyses are available online in the Zenodo repository (Österman et al. 2026a).

 Images and terminology

We photographed the specimens using a Sony Alpha 7R V camera body mounted on a macro rail, which enabled us to control and incrementally move the camera between shots. Photos were captured using an extension tube, a relay lens, and Mitutoyo Plan Apo objectives with 2.5×, 5×, and 20× magnifications. We captured multiple images at successive focal depths and combined them using the software Helicon Focus v. 7.7.5 (by Helicon Soft Ltd) to produce composite layer images with extended depth of field. We carried out final image adjustments in Adobe Photoshop CC to ensure accurate representation of the specimen’s morphological features.

We based our species descriptions largely on the format used in Gauld and Ward (2000) to describe species of Brachycyrtus. However, morphological terminology follows Broad et al. (2018), except for male genitalia that follow Dal Pos et al. (2023). The morphological terminology used for the propodeum is also shown as a figure in the supplementary data (Österman et al. 2026a). We provide less detailed collection information for non-type material below.

 Keys and diagnoses

We provide updated keys for all Neotropical and Afrotropical species. These are based on the existing keys in Gauld and Ward (2000), Nascimento and Fernandes (2024), and Di Giovanni and Varga (2021), with the Neotropical key updated to include our two new species, and the Afrotropical key updated to include two additional species from Madagascar and intended as a complement to that of Di Giovanni and Varga (2021).

We provide brief diagnoses for all Neotropical and Afrotropical species. These are minimal diagnoses that take into account the changes introduced by the description of two new Neotropical species, and the inclusion of two Afrotropical species from Madagascar. They should ideally be used as a complement to the more extensive diagnoses in Nascimento and Fernandes (2024) and Di Giovanni and Varga (2021). For the two new species we describe, we included more extensive diagnoses. The character matrix underlying the keys and diagnoses is available in the supplementary data (Österman et al. 2026a).

 Repositories

USNM National Museum of Natural History, Smithsonian Institution, Washington, DC, USA (Seán Brady).

UNMSM Museo de Historia Natural, Universidad Nacional Mayor de San Marcos, Lima, Peru (Mabel Alvarado Gutiérrez).

ZMUT Zoological Museum, Department of Biodiversity Sciences, University of Turku, Turku, Finland (Ilari Sääksjärvi).

 Results Species richness

The number of species collected by Malaise trapping in Ugandan forest and farmland peaked at two species (Fig. 2). Trapping in primary forest in Peru in 1998 and 2000 collected five species, with species still accumulating at the end of the sampling campaigns (Fig. 2). Trapping in secondary forest in Peru in 2011 collected two species, at a significantly lower rate than in the 1998 and 2000 campaigns, with species still accumulating at the end of the campaign (Fig. 2).

10.3897/jhr.99.190905.figure2 D70DBD2C-6680-59C6-A460-D86931C222D1

Species rarefaction curves of brachycyrtines collected in Malaise traps in Allpahuayo-Mishana in Peru (Amazon 1998, 2000, 2011), Los Amigos in Peru (Amazon 2008) and Kibale National Park in Uganda (Uganda 2014–2015). The curves are sample-based and show the accumulation rates of species per individual collected, with 84% confidence intervals.

https://binary.pensoft.net/fig/1762384 Phenology and habitat use

The two Ugandan species, B. cerrettii Di Giovanni, 2021 and B. antoninoi Di Giovanni, 2021, were mainly collected in Malaise traps during the two dry seasons in December–February and June–August, at a rate reaching about 0.01 individuals per trap per day (Fig. 3). The two Peruvian species with a sufficient sample size for analyses, B. oculatus Cushman, 1936 and B. veriatrix Gauld & Ward, 2000, did not show any clear phenological pattern but were collected at a higher rate than in Uganda, reaching 0.04 individuals per trap per day (Fig. 3).

10.3897/jhr.99.190905.figure3 96612615-08A9-5813-9059-FAD0D38FFDF1

Number of brachycyrtines collected in Malaise traps in Peru (1998, 2000, 2011) and Uganda (2014–2015). The catches of each species are stacked (colour coded by species, as individuals per day per trap). Rainfall has been smoothed by taking the average of the past 21 days. Catches are averaged over the sampling period, which for most Ugandan samples was approximately 14 days, and for most Peruvian samples, approximately 7, 14, or 21 days. Only the two Peruvian (B. veriatrix and B. oculatus) and two Ugandan species (B. cerrettii and B. antoninoi) with reasonable total sample sizes (n ≥ 20) are shown.

https://binary.pensoft.net/fig/1762385

Of the two Ugandan species, B. cerrettii was mainly collected in primary and disturbed forest, and not at all in the more human-impacted clearcut plantation or farmland (Fig. 4). B. antoninoi was collected in all Ugandan habitat types except for swampy primary forest (Fig. 4). The two Peruvian species with a sufficient sample size for analyses were mainly collected in white sand forest, or during the 2011 collecting in secondary forest (Fig. 5).

10.3897/jhr.99.190905.figure4 D28C303C-C08F-536D-8651-3AE2C3ED464E

Number of brachycyrtine individuals collected during a year of collecting with 34 Malaise traps in Uganda. Traps were in five habitat types forming a successional gradient: primary forest, swampy primary forest, disturbed forest, clearcut former plantations, and farmland. The plots include a total of 49 specimens, but do not include one Brachycyrtus antoninoi and one B. cerrettii specimen that came from samples that were unrepresentative of a typical catch.

https://binary.pensoft.net/fig/1762386 10.3897/jhr.99.190905.figure5 C0C7B841-45C7-5DCC-A054-9A90059B930D

Number of brachycyrtines collected during a year of collecting with 17 Malaise traps in Peru (year 2000), and during two shorter collecting events at the same site in Peru (years 1998, 2011). Traps were in three habitat types in 1998 and 2000: clay forest, loamy soil forest, and white sand forest. Traps were in secondary forest in 2011. The plots include a total of 58 specimens of the two species with reasonable total sample sizes (n ≥ 20).

https://binary.pensoft.net/fig/1762387 Taxonomy

Neotropical brachycyrtines

Key to Neotropical species of <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="subfamily" reg="Brachycyrtinae">Brachycyrtinae</tp:taxon-name-part></tp:taxon-name>

This key builds on the keys in Gauld and Ward (2000) and Nascimento and Fernandes (2024) and includes the two new species described herein. We have only examined physical specimens of eleven of the species (which we have collected); the other three, for which we only examined images or written descriptions, are marked with an asterisk *. Figure references that appear as “NF: fig.” refer to the figures in Nascimento and Fernandes (2024), whereas “Fig.” refer to the figures in this work.

1 Propodeum with area superomedia separated from area petiolaris by posterior transverse carina (NF: fig. 5A); tergite 2 with strong oblique thyridium anteriorly (NF: fig. 6A); eye with a deep impression opposite antennal insertion (NF: fig. 7A) B. pretiosus Cushman, 1936 *
– Propodeum with area superomedia confluent with area petiolaris (Fig. 7C, NF: fig. 5B); tergite 2 without distinct thyridium (NF: fig. 6B); eye with a shallow impression opposite antennal insertion (Fig. 9D, NF: fig. 7B) 2
2 Propodeum granulate and weakly polished (Fig. 7C) 3
– Propodeum generally smooth (without granulate sculpture) and polished (Fig. 13D) 8
3 Propodeum completely without posterior transverse carina (NF: fig. 9B); flagellum without coloured (sub)apical bands dorsally (Fig. 9A, B) B. granulatus Österman & Sääksjärvi, sp. nov.
– Propodeum with part of posterior transverse carina present (Fig. 17 B, NF: fig. 9A), delimiting area dentipara posteriorly; flagellum with (Fig. 7A, B, Fig. 11) or without (sub)apical coloured bands dorsally 4
4 Propodeum without anterior transverse carina separating area dentipara from area externa (NF: fig. 9A); flagellum uniformly blackish dorsally (Fig. 14A, or very rarely with a yellow band cf. Fig. 14B); apex of ovipositor tapered to an elongate point (NF: fig. 48F) B. veriatrix Gauld & Ward, 2000
– Propodeum with anterior transverse carina separating area dentipara from area externa (Fig. 13D), but can be reduced or incomplete (as in Fig. 7C); flagellum yellowish brown with apical segments blackish (Fig. 12), with (Fig. 11) or without (Fig. 12) a whitish subapical band; apex of ovipositor with dorsal valve rather abruptly rounded (NF: fig. 18A) or if rather elongate (NF: fig. 40F) then area basalis laterally delineated (NF: fig. 40G) 5
5 Propodeum with posterior transverse carina absent most laterally, not delineating area coxalis anteriorly (NF: fig. 11A) B. oculatus Cushman, 1936
– Propodeum with posterior transverse carina present most laterally, delineating area coxalis anteriorly (NF: fig. 11B) 6
6 Mesoscutum with notaulus impressed most anteriorly (NF: fig. 14A); flagellum with white subapical band (Fig. 7A, B); area basalis of propodeum not laterally delineated (NF: fig. 30G) B. convergens Cushman, 1936
– Mesoscutum without notaulus (NF: fig. 14B); flagellum without whitish subapical band (Fig. 8) or if with whitish subapical band (Fig. 11) then area basalis of propodeum laterally delineated (NF: fig. 40G) 7
7 Propodeum with area basalis not delineated laterally and anterior transverse carina complete latero-medially (NF: fig. 23A); head without distinct ocellar carina (NF: fig. 22A); flagellum without whitish subapical band (Fig. 8) B. cosmetus (Walkley, 1956)
– Propodeum with area basalis mostly delineated laterally and anterior transverse carina incomplete latero-medially (NF: fig. 23B); head with ocellar carina connecting the posterior margins of the foveae of the lateral ocelli (NF: fig. 22B); flagellum with whitish subapical band (Fig. 11) B. ocellicarinatus Nascimento & Fernandes, 2024
8 Propodeum with area dentipara and area lateralis confluent, forming area posteroexterna (NF: fig. 16A) 9
– Propodeum with area dentipara and area lateralis separated by the lateral longitudinal carina (NF: fig. 16B) 10
9 Propodeum with posterior transverse carina present latero-medially, delimiting area dentipara posteriorly (NF: fig. 25A) B. walkleyae Gauld & Ward, 2000
– Propodeum completely without posterior transverse carina (NF: fig. 25B) B. amazonensis Nascimento & Fernandes, 2024
10 Mesoscutum predominantly reddish brown (NF: fig. 17A); ovipositor often with dorsal valve stout, apically rather abruptly rounded or tapered (NF: fig. 18A) 11
– Mesoscutum yellowish white with three longitudinal black marks (NF: fig. 17B); ovipositor with dorsal valve apically fairly evenly tapered to a point (Fig. 13C) 13
11 Propodeum with posterior transverse carina present latero-medially, delimiting area dentipara posteriorly (NF: fig. 25A) B. obelix Gauld & Ward, 2000 *
– Posterior transverse carina completely absent (NF: fig. 25B) 12
12 Epomia strong; scutellum black; tergite 2 of ♀ slender, 1.3–1.4× as long as posteriorly broad B. noggius Gauld & Ward, 2000 *
– Epomia absent; scutellum orange (NF: fig. 36C); tergite 2 of ♀ stouter, 1.0–1.1× as long as posteriorly broad (NF: fig. 36C) B. muesebecki Walkley, 1956
13 Posterior transverse carina thin or absent, either rather weakly delineating area dentipara posteriorly or not at all (Fig. 17B–D); flagellum uniformly brownish (Fig. 16); without C-shaped black band along anterior margin of mesopleuron (Fig. 16) B. xorix Gauld & Ward, 2000
– Posterior transverse carina strong and clearly delineating area dentipara posteriorly (Fig. 13D); flagellum yellowish with apical segments black (Fig. 13A); C-shaped black band along anterior margin of mesopleuron (Fig. 13A) B. politus Österman & Sääksjärvi, sp. nov.
Animalia Hymenoptera Ichneumonidae EC0E781F-C4AA-5D9D-B3C0-D741F7EDE0E7 Brachycyrtus amazonensis Nascimento & Fernandes, 2024 Fig. 6 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of posterior transverse carina of propodeum entirely absent, propodeum smooth rather than granulate, and lateral longitudinal carina of propodeum absent between areas dentipara and lateralis.

10.3897/jhr.99.190905.figure6 19A9C077-0F26-54D2-9A5E-BC1DA170F184

Brachycyrtus amazonensis, habitus in lateral view. A. Non-type ♀ (http://mus.utu.fi/ZMUT.48477); B. Non-type ♂ (http://mus.utu.fi/ZMUT.48480). Scale bars: 1 mm.

https://binary.pensoft.net/fig/1762388 Material examined. Non-type material.

Ecuador • 3 ♀♀; Orellana, Onkone Gare; 1994–1995; T.L. Erwin et al. leg.; canopy fogging; ZMUT (on loan from USNM) http://mus.utu.fi/ZMUT.48477, http://mus.utu.fi/ZMUT.48478, http://mus.utu.fi/ZMUT.48479. • 1 ♂; same data as for preceding; Orellana, Tiputini; 1998; ZMUT (on loan from USNM) http://mus.utu.fi/ZMUT.48480.

 Distribution.

Brazil (Nascimento and Fernandes 2024). New: Ecuador.

 Animalia Hymenoptera Ichneumonidae 52A88C8F-C170-5211-B9D5-B5A65D1393E0 Brachycyrtus convergens Cushman, 1936 Fig. 7 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of mesoscutum with impressed notaulus, propodeum granulate, and lateral longitudinal carina of propodeum present between areas dentipara and lateralis. The white subapical band on the flagellum is a useful additional character if the lateral longitudinal carina of the propodeum is unclear.

10.3897/jhr.99.190905.figure7 7893D6F9-4394-56B3-A57C-608D0E2BC723

Brachycyrtus convergens. A. Non-type ♀ (http://mus.utu.fi/ZMUT.48483); B, C. Non-type ♂ (http://mus.utu.fi/ZMUT.48481): A, B. Habitus in lateral view; C. Propodeum in dorsal view. Scale bars: 1 mm.

https://binary.pensoft.net/fig/1762389 Material examined. Non-type material.

Ecuador • 1 ♀, 1 ♂; Orellana, Onkone Gare; 1996; T.L. Erwin et al. leg.; canopy fogging; ZMUT (on loan from USNM) http://mus.utu.fi/ZMUT.48481, http://mus.utu.fi/ZMUT.48482. • 1 ♀; same data as for preceding; Orellana, Tiputini; 1998; ZMUT (on loan from USNM) http://mus.utu.fi/ZMUT.48483.

 Description.

Male. Similar to female (see description in Gauld and Ward 2000) except with 27 flagellomeres (females with 29+ flagellomeres) and black mark on tergite 2 almost straight (V-shaped in female).

 Distribution.

Brazil (Walkley 1956; Nascimento and Fernandes 2024); Costa Rica, Panama (Gauld and Ward 2000). New: Ecuador.

 Remarks.

The anterior transverse carina (ATC) of the propodeum is more or less absent in all our examined specimens (Fig. 7C), unlike the examined specimens in Gauld and Ward (2000) and Nascimento and Fernandes (2024). In the image in Nascimento and Fernandes (2024, fig. 30), the ATC is complete, although not very strong. The strength of the ATC can vary within Neotropical species of Brachycyrtus, as in our specimens of B. oculatus the ATC is variably reduced, varying from being latero-medially complete but weak to being absent near the antero-lateral black mark. Furthermore, Gauld and Ward (2000) noted that the examined females of B. convergens have 30–31 flagellomeres, one or two more than our female specimens. We interpret these differences as intraspecific variation within the species.

 Animalia Hymenoptera Ichneumonidae A09255C8-D981-5D8F-92D8-30BB6FB1E7E5 Brachycyrtus cosmetus (Walkley, 1956) Fig. 8 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of mesoscutum without impressed notaulus, propodeum granulate, latero-median carina by area basalis absent, anterior transverse carina present between areas dentipara and externa, and posterior transverse carina of propodeum delimiting areas coxalis and postero-externa.

10.3897/jhr.99.190905.figure8 93E37FDF-068D-5294-9045-9A6FC25567A7

Brachycyrtus cosmetus, non-type ♀ (http://mus.utu.fi/ZMUT.48569), habitus in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762390 Material examined. Non-type material.

French Guiana • 1 ♀ Roura, Orapu; 2016; Société entomologique Antilles-Guyane leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48569.

 Distribution.

Brazil, Costa Rica, Suriname, Trinidad and Tobago, Venezuela (Gauld and Ward 2000; Nascimento and Fernandes 2024); Mexico (González–Moreno and Bordera 2011); Panama (Collantes 2011). New: French Guiana.

 Animalia Hymenoptera Ichneumonidae CDD1D802-0B3A-509B-AB4F-9C413B8A813E Brachycyrtus granulatus https://zoobank.org/10F794E7-9192-436B-B99C-73FE3C711779 Österman & Sääksjärvi sp. nov. Fig. 9 Material examined. <italic>Holotype</italic>.

Peru • ♀; Madre de Dios, Pakitza Rio Manu, BIOLAT Biological Station, lot #184; 11.9464°S, 71.2833°W; alt. 356 m; 4 Oct. 1991; M.G. Pogue & T.L. Erwin leg.; canopy fogging; ZMUT (on loan from USNM) http://mus.utu.fi/ZMUT.48513.

10.3897/jhr.99.190905.figure9 C3437163-94C2-58EB-97C9-C2AB7A5B111F

Brachycyrtus granulatus sp. nov. A. Paratype ♂ (http://mus.utu.fi/ZMUT.48515); B–E. Holotype ♀ (http://mus.utu.fi/ZMUT.48513): A, B. Habitus in lateral view; C. Propodeum in antero-dorsal view; D. Face in frontal view; E. Ovipositor in lateral view. Scale bars: 1 mm.

https://binary.pensoft.net/fig/1762391 <italic>Paratypes</italic>.

Peru • 1 ♀; Loreto, Iquitos, Allpahuayo-Mishana National Reserve, trap H1 on clay; 3.9489°S, 73.4212°W; 28 Dec. 2000–23 Jan. 2001; I.E. Sääksjärvi et al. leg.; Malaise trapping; ZMUT (on loan from UNMSM) http://mus.utu.fi/ZMUT.48514. Ecuador • 1 ♂; Orellana, Onkone Gare, lot #1570; 0.6571°S, 76.453°W; alt. 216 m; 22 Jun. 1996; T.L. Erwin et al. leg.; canopy fogging; ZMUThttp://mus.utu.fi/ZMUT.48515.

 Diagnosis.

This new species can easily be separated from other Neotropical species of Brachycyrtus by the combination of propodeum granulate and posterior transverse carina entirely absent. Additional helpful characteristics include: area basalis septate and not laterally delineated; anterior transverse carina complete to pleural carina; flagellum without coloured subapical bands.

 Description.

Female: fore wing length about 4.2 mm. Head. Mandible slender with dorsal tooth broader than ventral, oblique and dorsally pointed; eye with a weak impression in periphery opposite antennal insertion; ocelli more or less forming an equilateral triangle, the posterior one separated from eye by about 1.4× its own maximum diameter; posterior ocellar carina absent. Flagellum slender, not distinctly clavate, with 37 flagellomeres. Mesosoma. Pronotum without a discernible epomia; mesoscutum polished with fine, close setiferous punctures over entire surface, without discernible notaulus, and without antero-lateral crest; scutoscutellar groove broad and rather shallow; mesosternal region rather short, with a distinct central transverse carina posteriorly. Propodeum granulate over surface with sparse setae; area superomedia not delineated posteriorly, confluent with area petiolaris; area basalis septate and not laterally delineated; area externa and area spiracularis confluent; anterior transverse carina complete to pleural carina; posterior transverse carina absent, area dentipara not delineated posteriorly nor laterally by the short lateral longitudinal carina. Fore wing with 1cu-a distal to base of M&RS by 1.5–1.6× its own length. Metasoma. Tergite 2 without an impressed thyridium, moderately stout, about 1.1× as long as posteriorly broad: tergite 3 polished with fine setiferous punctures, with a flat thyridium anteriorly that is not impressed. Ovipositor projecting beyond apex of metasoma by 0.9× length of hind tibia, its apex without a distinct nodus, evenly and moderately strongly tapered to a point, ventral valve with about four small teeth.

Colour: Head yellow with interocellar area and continuous occipital mark black; antenna brownish with basal half ventrally yellowish. Mesosoma yellow with three longitudinal stripes on mesoscutum, scutoscutellar groove, central scutellum and metanotum, tegula, diagonal central band and two patches, one upper and one lower, anterior to it on mesopleuron and antero-lateral patches on propodeum black; wings uncoloured; fore and mid leg yellow with dorsal stripe on femur and tibia, and tarsus apically infuscate; hind leg yellow other than basal marks on coxa, trochanter other than dorsally, lateral stripes on femur, tibia other than centrally and tarsus other than most basally blackish. Metasoma yellow with first sternite and petiole, broad basal marks on tergites 2+, which are slightly V-shaped on tergites 2–3, black; ovipositor sheath black.

Male: similar to female except with 34 flagellomeres and black marks on tergites 2–3 straight.

Etymology. The specific epithet refers to the granulate sculpture of the propodeum.

 Distribution.

Ecuador, Peru.

 Biology.

The host(s) are unknown.

 Remarks.

The paratype female lacks the black patches anterior to the diagonal central band on the mesopleuron (Fig. 9A, B).

 Animalia Hymenoptera Ichneumonidae D09CE59A-CE0C-52E1-AF13-75CCD78D1E26 Brachycyrtus muesebecki Walkley, 1956 Fig. 10 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of mesoscutum predominantly reddish brown, posterior transverse carina of propodeum entirely absent, and without epomia.

10.3897/jhr.99.190905.figure10 D741A36D-9935-5C51-9A62-C1C819DF6C67

Brachycyrtus muesebecki, non-type ♀ (http://mus.utu.fi/ZMUT.48486), habitus in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762392 Material examined. Non-type material.

Ecuador • 2 ♀♀; Orellana, Tiputini; 1999; T.L. Erwin et al. leg.; canopy fogging; ZMUT (on loan from USNM) http://mus.utu.fi/ZMUT.48484, http://mus.utu.fi/ZMUT.48485. Peru • 1 ♀; Loreto, Iquitos, Allpahuayo-Mishana National Reserve; 1998; I.E. Sääksjärvi & R. Jussila et al. leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48486.

 Distribution.

Brazil (Walkley 1956). New: Ecuador, Peru.

 Remarks.

The metanotum of our specimens is entirely orange unlike the holotype which has the metanotum black-marked. The colouration and, for example, propodeal carination is otherwise similar to the holotype. We interpret this difference as intraspecific variation within the species.

We provide as new information for the key to Neotropical species above also the following characters (based on non-type material): epomia absent; tergite 2 of female 1.0–1.1× as long as posteriorly broad.

 Animalia Hymenoptera Ichneumonidae 161B2B81-27C7-567C-A8D8-200D383B1A9F Brachycyrtus noggius Gauld & Ward, 2000 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of mesoscutum predominantly reddish brown, posterior transverse carina absent behind area dentipara, and epomia present.

 Material examined.

No physical specimens examined. The diagnostic characters are based on written descriptions in Gauld and Ward (2000).

 Animalia Hymenoptera Ichneumonidae 373043B3-35B8-5BE0-8226-851BB96A1C5F Brachycyrtus obelix Gauld & Ward, 2000 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of mesoscutum predominantly reddish brown, lateral longitudinal carina of propodeum present between areas dentipara and lateralis, and posterior transverse carina present latero-medially so that area dentipara is separated from area postero-externa, but area lateralis is confluent with area coxalis.

 Material examined.

No physical specimens examined. The diagnostic characters are based on written descriptions in Gauld and Ward (2000).

 Animalia Hymenoptera Ichneumonidae DCBA71C1-CF46-5A62-8B3C-C54C94D21958 Brachycyrtus ocellicarinatus Nascimento & Fernandes, 2024 Fig. 11 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of ocellar carina connecting posterior margins of the left and right ocellar fovea, propodeum granulate, and latero-median carina mostly delineating area basalis laterally.

10.3897/jhr.99.190905.figure11 8CB29D9F-B54E-5758-B4FC-215A0A490BB3

Brachycyrtus ocellicarinatus, non-type ♀ (http://mus.utu.fi/ZMUT.48490), habitus in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762393 Material examined. Non-type material.

Peru • 3 ♀♀; Loreto, Iquitos, Allpahuayo-Mishana National Reserve; 1998–1999; I.E. Sääksjärvi & R. Jussila et al. leg.; Malaise trapping; ZMUT (2 on loan from UNMSM) http://mus.utu.fi/ZMUT.48487, http://mus.utu.fi/ZMUT.48488, http://mus.utu.fi/ZMUT.48489. • 1 ♀. Same data as for preceding; 2000; I.E. Sääksjärvi et al. leg.; ZMUThttp://mus.utu.fi/ZMUT.48490.

 Distribution.

Brazil (Nascimento and Fernandes 2024). New: Peru.

 Animalia Hymenoptera Ichneumonidae 7B60ED31-E215-57DF-8092-69C415FC952E Brachycyrtus oculatus Cushman, 1936 Fig. 12 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of propodeum granulate, lateral longitudinal carina of propodeum short, and posterior transverse carina present only latero-medially, delimiting area dentipara posteriorly.

10.3897/jhr.99.190905.figure12 41D6177B-9B96-560C-8181-D2BF102B09C6

Brachycyrtus oculatus, non-type ♀ (http://mus.utu.fi/ZMUT.48498), habitus in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762394 Material examined. Non-type material.

Peru • 20 ♀♀; Loreto, Iquitos, Allpahuayo-Mishana National Reserve; 1998–1999; I.E. Sääksjärvi & R. Jussila et al.; Malaise trapping; ZMUT (10 on loan from UNMSM) http://mus.utu.fi/ZMUT.48491, http://mus.utu.fi/ZMUT.48492, http://mus.utu.fi/ZMUT.48493, http://mus.utu.fi/ZMUT.48494, http://mus.utu.fi/ZMUT.48495, http://mus.utu.fi/ZMUT.48496, http://mus.utu.fi/ZMUT.48497, http://mus.utu.fi/ZMUT.48498, http://mus.utu.fi/ZMUT.48499, http://mus.utu.fi/ZMUT.48500, http://mus.utu.fi/ZMUT.48501, http://mus.utu.fi/ZMUT.48503, http://mus.utu.fi/ZMUT.48504, http://mus.utu.fi/ZMUT.48505, http://mus.utu.fi/ZMUT.48506, http://mus.utu.fi/ZMUT.48507, http://mus.utu.fi/ZMUT.48508, http://mus.utu.fi/ZMUT.48509, http://mus.utu.fi/ZMUT.48510, http://mus.utu.fi/ZMUT.48512. • 3 ♀♀; same data as for preceding; 2000; I.E. Sääksjärvi et al. leg.; ZMUThttp://mus.utu.fi/ZMUT.48502, http://mus.utu.fi/ZMUT.48511, http://mus.utu.fi/ZMUT.48566.

 Distribution.

Brazil (Nascimento and Fernandes 2024); Costa Rica, Panama, Venezuela (Gauld and Ward 2000). New: Peru.

 Animalia Hymenoptera Ichneumonidae 652A02B8-9763-56F7-965A-231010249738 Brachycyrtus politus https://zoobank.org/6278D8BE-C303-4709-9B4C-D01CA3B4F189 Österman & Sääksjärvi sp. nov. Fig. 13 Material examined. <italic>Holotype</italic>.

Peru • ♀; Loreto, Iquitos, Allpahuayo-Mishana National Reserve, trap C2 on clay; 5–17 Nov. 1998; I.E. Sääksjärvi & R. Jussila et al. leg.; Malaise trapping; ZMUT (on loan from UNMSM) http://mus.utu.fi/ZMUT.48518.

10.3897/jhr.99.190905.figure13 88F0E383-55FD-5DAB-A4C5-85E883BD0950

Brachycyrtus politus sp. nov., holotype ♀ (http://mus.utu.fi/ZMUT.48518). A. Habitus in lateral view; B. Face in frontal view; C. Distal ovipositor in lateral view; D. Propodeum in dorsal view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762395 <italic>Paratypes</italic>.

Peru • 1 ♀; Same data as for holotype; trap E1 on white sand; 3.9434°S, 73.4114°W; 16 Apr.–3 May 2000; I.E. Sääksjärvi et al. leg.; ZMUThttp://mus.utu.fi/ZMUT.48516. • 1 ♀; Madre de Dios, Los Amigos, trap la1; 12.5632°S, 70.0973°W; alt. 280 m; 24–31 Jul. 2008; I. Gómez leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48517. • 1 ♀; Cuzco, Amarakaeri Communal Reserve; 12.916°S, 70.850°W; alt. 333–884 m; 17 Sep.–14 Nov. 2010; M. Vilchez & C. Castillo leg.; ZMUT (on loan from UNMSM) http://mus.utu.fi/ZMUT.48519.

 Diagnosis.

This species can be separated from other Neotropical species of Brachycyrtus by the combination of the following characteristics: propodeum polished and sparse punctate (as opposed to granulate), area dentipara completely separated from area lateralis by the lateral longitudinal carina, posterior transverse carina strong and clearly delineating area dentipara posteriorly, mesoscutum yellowish with three longitudinal black stripes. Additional helpful characteristics include: flagellum yellowish with apical segments black, C-shaped black band along anterior margin of mesopleuron.

 Description.

Female: fore wing length about 4.7 mm. Head. Mandible slender with dorsal tooth broader than ventral, oblique and dorsally pointed; eye with a weak impression in periphery opposite antennal insertion; ocelli more or less forming an equilateral triangle, the posterior one separated from eye by 1.1–1.2× its own maximum diameter; posterior ocellar carina absent. Flagellum slender, not distinctly clavate, with 39–41 flagellomeres. Mesosoma. Pronotum without a discernible epomia; mesoscutum polished with quite dense setiferous punctures over entire surface, without discernible notaulus, and without antero-lateral crest; scutoscutellar groove rather deeply impressed but broad, U-shaped; mesosternal region rather short, with a distinct central transverse carina posteriorly. Propodeum polished, with rather sparse setiferous punctures, without punctures centrally; area superomedia not delineated posteriorly, confluent with area petiolaris; area basalis septate and not laterally delineated; area externa and area spiracularis confluent; anterior transverse carina complete to pleural carina; lateral longitudinal carina complete behind anterior transverse carina; area dentipara clearly delineated; posterior transverse carina strong but incomplete centrally and most laterally, not delineating area coxalis anteriorly. Fore wing with 1cu-a distal to base of M&RS by about 1.2× its own length. Metasoma. Tergite 2 without an impressed thyridium, moderately stout, about as long as posteriorly broad: tergite 3 polished with fine setiferous punctures, with a flat thyridium anteriorly that is not impressed. Ovipositor projecting beyond apex of metasoma by about 0.9× length of hind tibia, its apex without a distinct nodus, evenly and rather weakly tapered to a point, ventral valve with about four small teeth.

Colour: Head yellow with interocellar area and separated occipital mark black; antenna yellowish with roughly flagellomeres 21+ black. Mesosoma yellow with three longitudinal stripes on mesoscutum, scutoscutellar groove, posterior scutellum and metanotum, tegula, C-shaped band along anterior margin and diagonal central band on mesopleuron, band bordering mesopleuron and antero-lateral patches on propodeum black; wings hyaline; legs yellowish with basal marks on hind coxa and hind trochanter other than dorsally black. Metasoma yellow with petiole and broad, straight basal marks on tergites 2+ brownish; ovipositor sheath black.

Male: unknown.

Etymology. The specific epithet is derived from the Latin word politus, meaning polished or smooth, referring to the species’ general appearance and surface texture.

 Distribution.

Peru.

 Biology.

The host(s) are unknown.

 Remarks.

B. politus resembles most B. xorix but can be separated from it by the strong posterior transverse carina clearly delineating area dentipara posteriorly (Fig. 13D; in B. xorix area dentipara is at most weakly delineated posteriorly), the apical black band of the otherwise yellowish flagellum (Fig. 13A; in B. xorix the brownish flagellum has no coloured bands), and the C-shaped black band along the anterior margin of the mesopleuron (Fig. 13A; lacking in B. xorix). B. politus is also a noticeably larger species than B. xorix.

 Animalia Hymenoptera Ichneumonidae 1B86B5EA-2597-59FC-AB19-DBD7402486E6 Brachycyrtus pretiosus Cushman, 1936 Brief diagnosis.

Told apart from all currently known Neotropical species by the presence of the posterior transverse carina behind the area superomedia.

 Material examined.

No physical specimens examined. The diagnostic characters are based on written descriptions in Gauld and Ward (2000).

 Animalia Hymenoptera Ichneumonidae 0DB9F9FD-26A3-5286-9877-E022E7BF6480 Brachycyrtus veriatrix Gauld & Ward, 2000 Fig. 14 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of propodeum granulate and anterior transverse carina of propodeum absent between areas dentipara and externa. In uncertain cases, the uniformly blackish dorsal flagellum (which can very rarely have a yellow median band), and the apex of the ovipositor being tapered to an elongate point, are useful additional characters.

10.3897/jhr.99.190905.figure14 26542FCB-76B2-562D-8FA1-FDCFA03A18B2

Brachycyrtus veriatrix. A. Non-type ♀ (http://mus.utu.fi/ZMUT.48551), habitus in lateral view; B. Non-type ♀ (http://mus.utu.fi/ZMUT.48559), antenna in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762396 Material examined. Non-type material.

French Guiana • 2 ♀♀ Roura; 2016–2017; Société entomologique Antilles-Guyane leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48568, http://mus.utu.fi/ZMUT.57764. • 3 ♀♀; same data as for preceding; Saül; 2011–2012; ZMUThttp://mus.utu.fi/ZMUT.48521, http://mus.utu.fi/ZMUT.48522, http://mus.utu.fi/ZMUT.48523. Peru • 3 ♀♀; Loreto, Iquitos, Allpahuayo-Mishana National Reserve; 1998; I.E. Sääksjärvi & R. Jussila et al. leg; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48534, http://mus.utu.fi/ZMUT.48552, http://mus.utu.fi/ZMUT.48553. • 15 ♀♀; same data as for preceding; 2000; I.E. Sääksjärvi et al. leg.; ZMUThttp://mus.utu.fi/ZMUT.48524, http://mus.utu.fi/ZMUT.48525, http://mus.utu.fi/ZMUT.48526, http://mus.utu.fi/ZMUT.48527, http://mus.utu.fi/ZMUT.48528, http://mus.utu.fi/ZMUT.48529, http://mus.utu.fi/ZMUT.48530, http://mus.utu.fi/ZMUT.48531, http://mus.utu.fi/ZMUT.48532, http://mus.utu.fi/ZMUT.48533, http://mus.utu.fi/ZMUT.48555, http://mus.utu.fi/ZMUT.48556, http://mus.utu.fi/ZMUT.48557, http://mus.utu.fi/ZMUT.48558, http://mus.utu.fi/ZMUT.48559. • 17 ♀♀; same data as for preceding; 2011; I. Gómez & I.E. Sääksjärvi leg.; ZMUT (10 on loan from UNMSM) http://mus.utu.fi/ZMUT.48520, http://mus.utu.fi/ZMUT.48535, http://mus.utu.fi/ZMUT.48536, http://mus.utu.fi/ZMUT.48537, http://mus.utu.fi/ZMUT.48538, http://mus.utu.fi/ZMUT.48539, http://mus.utu.fi/ZMUT.48540, http://mus.utu.fi/ZMUT.48541, http://mus.utu.fi/ZMUT.48542, http://mus.utu.fi/ZMUT.48543, http://mus.utu.fi/ZMUT.48544, http://mus.utu.fi/ZMUT.48550, http://mus.utu.fi/ZMUT.48545, http://mus.utu.fi/ZMUT.48546, http://mus.utu.fi/ZMUT.48547, http://mus.utu.fi/ZMUT.48548, http://mus.utu.fi/ZMUT.48549. • 1 ♀; same data as for preceding; I. Gómez & I.E. Sääksjärvi leg.; sweep netting; ZMUThttp://mus.utu.fi/ZMUT.48551. Nicaragua • 1 ♀; Matagalpa, Cerro Musún Natural Reserve; 2011; LLAMA project, Longino et al. leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48554.

 Distribution.

Brazil, Costa Rica, Ecuador, Venezuela (Gauld and Ward 2000; Nascimento and Fernandes 2024); Mexico (González–Moreno and Bordera 2011). New: French Guiana, Peru, Nicaragua.

 Remarks.

In one of our examined specimens (Fig. 14B) the dorsal flagellum is black with a median wide yellow band, and another specimen has such an apical band, whereas the rest of our specimens have a uniformly black dorsal flagellum (Fig. 14A). The yellow-banded specimens are otherwise similar to the other specimens. Hence, we interpret these rarely occurring bands as intraspecific variation within the species.

 Animalia Hymenoptera Ichneumonidae 27CD8418-0B2C-57F6-BBE8-D725A086DA5F Brachycyrtus walkleyae Gauld & Ward, 2000 Fig. 15 Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of propodeum smooth rather than granulate, lateral longitudinal carina of propodeum absent between areas dentipara and lateralis, and posterior transverse carina posteriorly delimiting area dentipara.

10.3897/jhr.99.190905.figure15 851AF340-A480-519C-B2F7-73FDE7FC829C

Brachycyrtus walkleyae, non-type ♀ (http://mus.utu.fi/ZMUT.48561), habitus in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762397 Material examined. Non-type material.

Ecuador • 1 ♀; Orellana, Onkone Gare; 1995; T.L. Erwin et al. leg.; canopy fogging; ZMUT (on loan from USNM) http://mus.utu.fi/ZMUT.48562. French Guiana • 3 ♀♀; Roura; 2016; Société entomologique Antilles-Guyane leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.57763, http://mus.utu.fi/ZMUT.57765, http://mus.utu.fi/ZMUT.57766. • 1 ♀; same data as for preceding; Saül; 2011; ZMUThttp://mus.utu.fi/ZMUT.48560. Peru • 1 ♀; Loreto, Iquitos, Allpahuayo-Mishana National Reserve; 2011; I. Gómez & I.E. Sääksjärvi leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48561.

 Distribution.

Belize, Brazil, Costa Rica, Panama, Trinidad and Tobago (Gauld and Ward 2000). New: Ecuador, French Guiana, Peru.

 Animalia Hymenoptera Ichneumonidae D0F1DA5F-D675-5101-B640-4473CE26AEE9 Brachycyrtus xorix Gauld & Ward, 2000 Figs 16 , 17 Brachycyrtus zani Gauld & Ward, 2000, syn. nov. Brief diagnosis.

Told apart from all currently known Neotropical species by the combination of mesoscutum yellowish white with three longitudinal black marks, propodeum smooth rather than granulate, lateral longitudinal carina of propodeum delimiting areas dentipara and lateralis, and posterior transverse carina varying between absent and thin behind area dentipara. Apart from the posterior transverse carina, B. xorix also differs from our new species B. politus Österman & Sääksjärvi in the colour of the flagellum and mesopleuron and in size.

10.3897/jhr.99.190905.figure16 9B5C38B9-5F45-5C98-AE52-06D8D4050DEC

Brachycyrtus xorix, non-type ♀ (http://mus.utu.fi/ZMUT.48567), habitus in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762398 10.3897/jhr.99.190905.figure17 DC7BFB54-34B0-50D0-BA12-207459A882E9

Brachycyrtus xorix. A, C. Non-type ♂ (http://mus.utu.fi/ZMUT.48563); B. Non-type ♂ (http://mus.utu.fi/ZMUT.48564); D. Non-type ♂ (http://mus.utu.fi/ZMUT.48565): A. Habitus in lateral view; B–D. Postero-lateral propodeum in dorsal view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762399 Material examined. Non-type material.

Colombia • 1 ♀; Magdalena, Parque Nacional Natural Sierra Nevada de Santa Marta; 2001; J. Castillo leg.; Malaise trapping; ZMUThttp://mus.utu.fi/ZMUT.48567. Ecuador • 3 ♂♂; Orellana, Onkone Gare; 1996; T.L. Erwin et al. leg.; canopy fogging; ZMUT (2 on loan from USNM) http://mus.utu.fi/ZMUT.48563, http://mus.utu.fi/ZMUT.48564, http://mus.utu.fi/ZMUT.48565.

 Distribution.

Brazil (Nascimento and Fernandes 2024); Mexico (González-Moreno and Bordera 2012); Costa Rica, Panama, Peru, Trinidad and Tobago (Gauld and Ward 2000). New: Colombia, Ecuador.

 Remarks.

Originally, in Gauld and Ward (2000), B. xorix and B. zani were described as separate species based on the “sharp” posterior transverse carina (PTC) delineating area dentipara posteriorly (present only in B. xorix) and the “ill-defined” ventral black mark on the mesopleuron (present only in B. zani). However, specimens from Brazil (identified as B. zani in Nascimento and Fernandes 2024) and from Ecuador (here) lack both the PTC (Fig. 17D) and the ventral black mark on the mesopleuron (all our specimens, cf. Figs 16, 17A), implying minimally that the colouration of the mesopleuron cannot be used to separate the species (nor apparently any other difference in colouration). Thus, the sole diagnostic character is the presence or absence of the thin PTC. By studying other Neotropical brachycyrtine species, we have observed that some of the propodeal carinae can be variously reduced, varying from being complete but rather weak to more or less absent for at least a portion of the length (see, e.g., the remarks for B. convergens above). Particularly, the entire absence of a short carina can be expected if the carina is otherwise variable in development. This is evident for the PTC in our B. xorix specimens from Colombia and Ecuador as our specimens form a gradient in the reduction of the PTC; it is absent (or just very weakly indicated as on the right side in Nascimento and Fernandes 2024, fig. 57F) in one specimen (Fig. 17D), partially indicated in two specimens (Fig. 17C and the Colombian specimen in Fig. 16), and complete but thin (as in the examined B. xorix specimen in Nascimento and Fernandes 2024, fig. 54) in a fourth specimen (Fig. 17B). Hence, in the absence of DNA evidence to the contrary, we regard these diagnostic characters as intraspecific variation and Brachycyrtus zani Gauld & Ward, 2000 as a junior synonym of Brachycyrtus xorix Gauld & Ward, 2000.

Afrotropical brachycyrtines Key to Afrotropical species of <tp:taxon-name><tp:taxon-name-part taxon-name-part-type="subfamily" reg="Brachycyrtinae">Brachycyrtinae</tp:taxon-name-part></tp:taxon-name>

This key is intended as a complement to the key and detailed species descriptions of Di Giovanni and Varga (2021) for quick identification of the currently known species. Malagasy species have also been included (unlike in Di Giovanni and Varga 2021). We have only examined physical specimens of two of the species; the other three, for which we only examined images and written descriptions, are marked with an asterisk *.

1 Membranous patches on tergites 2–4 (Fig. 18A). (Mainland African species in forest.) B. cerrettii Di Giovanni, 2021
– No membranous patches on tergites 2–4 (Fig. 18B) 2
2 Tergite 1 anteriorly black; tergites 2–5 with pale postero-lateral patches (Fig. 18B). (Mainland African species.) B. antoninoi Di Giovanni, 2021
– Tergite 1 anteriorly mostly pale; tergites 2–5 posteriorly either pale both laterally and in middle or not pale (Fig. 18C–E) 3
3 Tergites 2–5 anteriorly dark, posteriorly pale, with the dark patch extending further back laterally than along the midline (Fig. 18C). (Mainland African species widespread in at least agricultural land, possibly also Madagascar.) B. lucchii Di Giovanni & Varga, 2021*
– Some of tergites 2–5 either not posteriorly pale or with a pale band that does not extend noticeably further forward along the midline than laterally (Fig. 18D–E). (Malagasy species.) 4
4 Tergites 3–5 mostly dark but with unclear pale patches posteriorly (Fig. 18D) B. luteoniger Seyrig, 1952*
– Tergites 2, 5 mostly red and tergites 3–5 anteriorly black and posteriorly pale (Fig. 18E) B. fianarensis Seyrig, 1952*
Animalia Hymenoptera Ichneumonidae AE5521B6-D149-5332-9EF6-B875DD8203D5 Brachycyrtus antoninoi Di Giovanni, 2021 Figs 19 , 20 , 21 Brief diagnosis.

Mainland African species. Told apart from all currently known African species by the colour pattern of the metasoma, with tergite 1 black except for postero-lateral pale spots, and tergites 2–5 with two postero-lateral patches that are paler than the rest of the tergite (cf. Figs 19B, 20, 21B); does not have membranous patches on tergites 2–4.

10.3897/jhr.99.190905.figure18 DBA48164-5B77-5AEF-9C53-EB7B8740F83D

Colour patterns and structure of the metasomal tergites, in dorsal view, of the five known Afrotropical brachycyrtine species for quick keying to species. A. Brachycyrtus cerrettii, non-type ♀ (http://mus.utu.fi/ZMUT.23057); B. B. antoninoi, non-type ♀ (http://mus.utu.fi/ZMUT.18277), dark colour morph; C. B. lucchii, drawing based on holotype images (Di Giovanni and Varga 2021); D. B. luteoniger, drawing based on holotype images (MNHN 2025b), with tergites 2, 7, and the tip of tergite 1 left out due to being unclear in the images; E. B. fianarensis, drawing based on holotype images (MNHN 2025a; van Noort 2026).

https://binary.pensoft.net/fig/1762400 10.3897/jhr.99.190905.figure19 EE7477D0-75E0-5CD4-BEE8-EA92DA01B31B

Brachycyrtus antoninoi¸ non-type ♀ (http://mus.utu.fi/ZMUT.18277), black colour morph, with the dark patches of the metasomal tergites black instead of pale red. A. Habitus in lateral view; B. Metasomal tergites in dorsal view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762401 10.3897/jhr.99.190905.figure20 7FFAD5C7-96D1-52DE-B18D-B3D887C569A5

Brachycyrtus antoninoi¸ non-type ♂ (http://mus.utu.fi/ZMUT.50763), black colour morph, with the dark patches of the metasomal tergites black instead of pale red, habitus in lateral view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762402 10.3897/jhr.99.190905.figure21 4A9983CF-62BF-50BD-A8CA-3A4B294AAF3F

Brachycyrtus antoninoi, non-type ♀ (http://mus.utu.fi/ZMUT.20633), red colour morph, with the dark patches of the metasomal tergites mostly pale red instead of black. A. Habitus in lateral view; B. Metasomal tergites in dorsal view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762403 Material examined. Non-type material.

Uganda • 21 ♀♀; Kibale National Park, Kanyawara; 2014–2015; T. Hopkins leg.; Malaise trapping; ZMUT. Côte D’Ivoire • 2♀♀, 4♂♂; Mont Tonkoui; 2018–2019; Y. Braet & A. Gué leg.; Malaise trapping; ZMUT. Data in the supplementary dataset (Österman et al. 2026a).

Male. Similar to female. The gonostyle is similar to B. lucchii (the only other Afrotropical brachycyrtine species for which the male is known): elongated and rod-like, which is otherwise rare in ichneumonids outside the Mesochorinae.

 Known material.

30 specimens: 23 ♀♀, 4♂♂ in ZMUT material, 3 ♀♀ in other material. Listed in the supplementary data (Österman et al. 2026a) and localities shown in Fig. 23.

 Distribution.

Kenya, Uganda (Di Giovanni and Varga 2021). New: Côte d’Ivoire.

 Biology.

In Uganda, B. antoninoi was mainly collected during the dry seasons in Malaise traps (Fig. 3), a pattern that we suspect is typical of idiobiont ectoparasitoids in the Ugandan material (based on the observed phenology of subfamilies Pimplinae, Rhyssinae, and Ophioninae). Unlike B. cerrettii, individuals were collected in a variety of habitat types, including one individual in farmland (Fig. 4). Of the nine known specimens outside our material, at least eight were likely collected in natural habitat (one at our site in Kibale National Park, one in Kakamega Forest in Kenya, six on Mont Tonkoui in Côte d’Ivoire), possibly also the remaining one if it was collected in Meru National Park, so B. antoninoi could be more a (semi) natural habitat than agricultural land species. Only females were collected in our Ugandan (flight interception) traps, which suggests the males may be less mobile, possibly staying near the area they pupated to mate. However, the collecting in Côte d’Ivoire does not match this pattern, collecting an admittedly small sample size of four males and two females in a similar trap to that used in Uganda.

 Remarks.

The Ugandan females vary in how dark their colour is: the colour of the dark patches on the metasoma varies from black (Figs 19B, 20) to a pale red (Fig. 21B), with some intermediate forms. The holotype of the species is close to the pale red end of this variation based on the images in Di Giovanni and Varga (2021, fig. 2).

 Animalia Hymenoptera Ichneumonidae 2853369A-D8FA-5DD5-83D6-1EB7408DBAF0 Brachycyrtus cerrettii Di Giovanni, 2021 Fig. 22 Brief diagnosis.

Mainland African species. Told apart from all currently known African species by the membranous patches on tergites 2–4 (Fig. 22B).

10.3897/jhr.99.190905.figure22 87C8D4BA-32CE-5E53-B730-01606122DBBB

Brachycyrtus cerrettii, non-type ♀ (http://mus.utu.fi/ZMUT.23057). A. Habitus in lateral view; B. Metasomal tergites in dorsal view. Scale bar: 1 mm.

https://binary.pensoft.net/fig/1762404 Material examined. Non-type material.

Uganda • 30 ♀♀; Kibale National Park, Kanyawara; 2014–2015; T. Hopkins leg.; Malaise trapping; ZMUT. Data in the supplementary dataset (Österman et al. 2026a).

 Known material.

31 specimens: 30 ♀♀ in ZMUT material, 1 ♀ in other material. Listed in the supplementary data (Österman et al. 2026a) and localities shown in Fig. 23.

10.3897/jhr.99.190905.figure23 952070BA-FCD2-5AEB-B9F6-01D249A3168D

Map of all known collecting localities of African brachycyrtines. Côte d’Ivoire: Mont Tonkoui (MT); Kenya: Kakamega Forest (KF), Meru (Me), Nairobi, Kasarani (NK); Madagascar: Bekily (Be), Fianarantsoa (Fi); Tanzania: Kilosa, Ilonga (KI); Uganda: Kawanda (Ka), Kibale National Park (KNP); Zambia: Lusaka (Lu); Zimbabwe: Chipinge district (Cd), Chishawasha (Ch). The localities are from the supplementary data (Österman et al. 2026a).

https://binary.pensoft.net/fig/1762405 Distribution.

Uganda (Di Giovanni and Varga 2021).

 Biology.

In Uganda, B. cerrettii was mainly collected during the dry seasons in Malaise traps (Fig. 3), a pattern that we suspect is typical of idiobiont ectoparasitoids in the Ugandan material (based on the observed phenology of subfamilies Pimplinae, Rhyssinae and Ophioninae). Most individuals were collected in primary forest, and none in clearcut plantation or the two traps in farmland (Fig. 4), which suggests the species may prefer undisturbed forest. Only females were collected in our (flight interception) traps, which suggests the males may be less mobile, possibly staying near the area they pupated to mate.

 Remarks.

Currently only known from one site, in Uganda: Kanyawara in Kibale National Park. However, we strongly suspect this is a widespread forest species, so it should be present in at least the Democratic Republic of Congo.

 Animalia Hymenoptera Ichneumonidae CB11B073-7CA4-51CA-B032-8A4D53DCB30B Brachycyrtus fianarensis Seyrig, 1952 Brief diagnosis.

Malagasy species. Told apart from all currently known African species by the colour pattern of the metasoma, with tergite 1 pale with a wide dark red band in the middle, tergite 2 more or less uniformly dark red (although with a hint of a posterior paler patch), tergites 3–4 with the anterior half black and posterior half pale, tergites 5–7 dark red (Fig. 18E). Does not have membranous patches on tergites 2–4.

 Material examined.

No physical specimens examined. The diagnostic characters are based on images of the holotype (MNHN 2025a; van Noort 2026).

 Known material.

1 specimen: none in ZMUT material, 1 ♀ in other material. Listed in the supplementary data (Österman et al. 2026a) and localities shown in Fig. 23.

 Distribution.

Madagascar (Seyrig 1952).

 Animalia Hymenoptera Ichneumonidae ED9A09B2-68C4-5DF6-BF8C-64FD9E75BC58 Brachycyrtus lucchii Di Giovanni & Varga, 2021 Brief diagnosis.

Probably a mainland African species (but possibly also Madagascar, see remarks). Told apart from all currently known Afrotropical species by the colour pattern of the metasoma, with tergite 1 pale with a dark band or patch in the middle, tergites 2–5 anteriorly dark and posteriorly pale, with the dark patch extending further back laterally than along the midline (Fig. 18C). Does not have membranous patches on tergites 2–4.

 Material examined.

No physical specimens examined. The diagnostic characters are based on images of the holotype (Di Giovanni and Varga 2021).

 Known material.

18 specimens: none in ZMUT material, 14 ♀♀ and 4 ♂♂ in other material. Listed in the supplementary data (Österman et al. 2026a) and localities shown in Fig. 23.

 Distribution.

Botswana (Benn 2025); Kenya, Tanzania, Uganda, Zambia, Zimbabwe (Di Giovanni and Varga 2021).

 Biology.

Many of the known specimens were collected in agricultural land or shrubland, e.g., in cotton fields or a “meadow in degraded shrub-/ grassland” (Di Giovanni and Varga 2021, also summarised in the list of known material in Österman et al. 2026a). No specimens were collected by us in Ugandan forest, despite the species having been observed in Uganda and our year of Malaise trapping catching 51 brachycyrtines of other species. B. lucchii thus seems to be a widespread agricultural land / open land species, likely absent from forest.

 Remarks.

Since Di Giovanni and Varga (2021), the species has been observed in Botswana (Benn 2025). Two other iNaturalist observations, one from South Africa (Taylor 2023) and the other from Madagascar (Wiesner 2022), look like B. lucchii, but could also be undescribed species.

 Animalia Hymenoptera Ichneumonidae 1D622501-68B7-57E4-A4F4-5B9A9A41A268 Brachycyrtus luteoniger Seyrig, 1952 Brief diagnosis.

Malagasy species. Told apart from all currently known African species by the colour pattern of the metasomal tergites, with tergites 3–5 mostly dark with a paler patch posteriorly, and tergite 1 anteriorly pale (Fig. 18D). The colour pattern resembles that of B. lucchii, but with smaller pale patches that do not extend anteriorly along the midline on the tergites. Does not have membranous patches on tergites 2–4.

 Material examined.

No physical specimens examined. The diagnostic characters are based on images of the holotype (MNHN 2025b).

 Known material.

1 specimen: none in ZMUT material, 1 ♀ in other material. Listed in the supplementary data (Österman et al. 2026a) and localities shown in Fig. 23. Seyrig (1952) mentions that there are other specimens, both female and male, but we do not know how many they are or where they are.

 Distribution.

Madagascar (Seyrig 1952).

 Discussion

Although brachycyrtine abundances in our samples were low and thus the number of collected specimens was small, the relative rates at which species accumulated in the Peruvian and Ugandan samples (Fig. 2) clearly show that there are more species at the Peruvian site. We earlier observed a similar higher species richness at our Peruvian site for the subfamily Rhyssinae (Hopkins et al. 2024). This matches many other previous studies showing that the Neotropics is generally richer in species than the Afrotropical region (e.g., Raven et al. 2020). This suggests that the greater number of currently known Neotropical Brachycyrtus species (14 species) than Afrotropical species (5 species) is at least partly due to a genuinely higher species richness in the Neotropics, not just because of different amounts of collecting.

Nevertheless, it is clear that both the Neotropical and especially the Afrotropical brachycyrtines are severely undersampled. Our Neotropical material contained two new species for science, and we got new (country level) distributional records for all collected Neotropical species. Rarefaction curves for our Peruvian site suggest that more species remain to be discovered there if sampling were to be continued, despite almost two years of collecting (Fig. 2). The first observation of brachycyrtines in mainland Africa was published as recently as five years ago (Di Giovanni and Varga 2021). We know of only 81 Afrotropical specimens, the majority of them (51) collected by us in Uganda, and the 6 from Côte d’Ivoire being new records and including the first record of the male of B. antoninoi. Three of the species are known from only one site (B. cerrettii, B. fianarensis, B. luteoniger; Fig. 23), one is known from just a few sites in Côte d’Ivoire, Kenya, and Uganda (B. antoninoi; Fig. 23), leaving only one species collected in more than three countries (B. lucchii; Fig. 23). Our entire knowledge of the brachycyrtines of Madagascar is based on two individuals collected in 1936 and 1937 (cf. known material listed in Österman et al. 2026a), plus to some extent a recent photo uploaded to iNaturalist (Wiesner 2022). iNaturalist observations also suggest there are either new distribution records or new species still to be discovered (see remarks for B. lucchii).

Geographically more extensive sampling in both the Neotropics and Afrotropics would not only discover further species and extend distribution records, but it would also allow more accurate analyses of the biology and species richness of brachycyrtines. By collecting extensively at Peruvian and Ugandan sites (Allpahuayo-Mishana, Los Amigos, and Kibale), we discovered that the Peruvian Allpahuayo-Mishana site has more brachycyrtine species than the Ugandan site. We also found that Ugandan species are mainly collected during the dry seasons (giving some additional support for them being idiobiont ectoparasitoids, cf. remarks of Brachycyrtus antoninoi), that Brachycyrtus cerrettii is likely a forest species and B. lucchii likely absent from forest, and that the Peruvian species may tentatively prefer white sand forest. The latter is interesting as white sand forests are rare in Western Amazonia, contain a high number of endemic species, and there are tentative signs they may generally contain fewer species than other kinds of rain forest (Gómez et al. 2017 found a weak signal of this for the subfamily Pimplinae). Collecting more brachycyrtines will, however, need some effort, at least if using Malaise traps: our Peruvian traps collected at most around 0.04 specimens per trap per day (Fig. 3), translating to about 25 days of trapping needed to catch one brachycyrtine wasp. This may indicate that brachycyrtine abundances are low in tropical rain forests. Ugandan maximum catches were a quarter of this (100 trap days to catch one wasp), and average rates as opposed to maximum peaks were much lower.

The proposed synonymisation of B. zani with B. xorix highlights a broader challenge in current brachycyrtine taxonomy: heavy reliance on the shapes of colour patches, and on potentially variable development of the propodeal carinae, as determining diagnostic characters. Hence, species delimitation and diagnoses may benefit greatly from geographically extensive sampling where, for example, individuals displaying intraspecific colour variation are discovered. In our view, this does not call into question the new species described herein, but care is needed when separating species in cases where there is variation in a morphological character, particularly of the type weak-to-reduced-to-absent (see the remarks for B. xorix for an example). Our keys to species should still work despite relying quite heavily on colouration and propodeal carinae as we have included notes on observed variation which could make identification difficult, and in some cases, we opted for using conditional statements despite their length to provide more characters.

 Acknowledgements

We thank the reviewers for their constructive comments and valuable feedback, which significantly improved the quality of this work. The collecting in Central and South America was supported or conducted by the late Terry Erwin, by John Longino (LLAMA project), Carol Castillo, Manuel Ahuite, Pekka Soini (late), J. Castillo, and the SEAG team. The collecting in Côte d’Ivoire was conducted by Yves Braet and Erena Dupont. The collecting in Uganda was supported by Heikki Roininen, Isaiah Mwesige, and the staff of the Makerere University Biological Field Station. Countless people helped process the Peruvian and Ugandan samples, including the staff of the Zoological Museum of the University of Turku, students of the university, and school pupils from the Turku region. These contributions are gratefully acknowledged.

The Ministry of Agriculture and the Ministry of Environment of Peru provided the collecting and export permits for the Peruvian samples. We appreciate the support of the Instituto de Investigaciones de la Amazonía Peruana (IIAP) for the field studies in Allpahuayo-Mishana. The required Ugandan research and export permits were issued by the Uganda National Council of Science and Technology (NS 504) and the Uganda Wildlife Authority.

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Proceedings of the Royal Society B 279(1748): 4694–4698. https://doi.org/10.1098/rspb.2012.1664 Veijalainen A, Sääksjärvi IE, Tuomisto H, Broad GR, Bordera S, Jussila R (2014) Altitudinal trends in species richness and diversity of Mesoamerican parasitoid wasps (Hymenoptera: Ichneumonidae). Insect Conservation and Diversity 7(6): 496–507. https://doi.org/10.1111/icad.12073 Wahl DB (1993) Cladistics of the ichneumonid subfamily Labeninae (Hymenoptera: Ichneumonidae). Entomologia Generalis 18: 1–105. https://doi.org/10.1127/entom.gen/18/1993/91 Walkley LM (1956) A tribal revision of the Brachycyrtine wasps of the world (Cryptinae-Ichneumonidae). Proceedings of the United States National Museum 106(3369): 315–329. https://doi.org/10.5479/si.00963801.106-3369.315 Wiesner F (2022) Brachycyrtus. iNaturalist observation. https://www.inaturalist.org/observations/121487072 [Accessed on 11.8.2026] Additional information Conflict of interest

The authors have declared that no competing interests exist.

 Ethical statement

No ethical statement was reported.

 Artificial Intelligence (AI) use

The authors accept full responsibility for the content of the manuscript, including the disclosure of any use of AI.

No AI tools were used in the preparation of this manuscript.

 Funding

The collecting, processing and publishing of the Ugandan material was supported by the Alfred Kordelin Foundation, the Entomological Society of Finland, the Finnish Cultural Foundation, Oskar Öflunds Stiftelse, Svensk-Österbottniska Samfundet, and Waldemar von Frenckells stiftelse (grants to Tapani Hopkins). The Peruvian sampling campaign was funded by the Finnish Kone Foundation (a grant awarded to the project: Biodiversity and multiple trophic interactions lead by Ilari E. Sääksjärvi) and Biological Interactions Graduate School (Ministry of Education and Culture, Finland). The Ministry of Education and Culture (Finland) and the Research Council of Finland funded Emil M. Österman’s doctoral research through the Sustainability Transformations Doctoral Education Pilot when writing this article.

 Author contributions

Conceptualization: TH, IES, EMÖ. Data curation: TH. Funding acquisition: IES, TH. Investigation: EMÖ, ICG, IES, TH. Project administration: EMÖ. Resources: TH, IES. Supervision: IES. Visualization: KMK, IAEÖ, TH. Writing - original draft: TH, IES, EMÖ. Writing - review and editing: IES, EMÖ, ICG, KMK, TH.

 Author ORCIDs

E.M. Österman https://orcid.org/0009-0008-8307-5804

T. Hopkins https://orcid.org/0000-0002-2256-0098

K.M. Kaunisto https://orcid.org/0000-0001-6665-0047

I.C. Gómez https://orcid.org/0009-0007-1752-8046

I.A.E. Österman https://orcid.org/0009-0002-9532-1060

I.E. Sääksjärvi https://orcid.org/0000-0002-8107-5607

 Data availability

The data and analyses are in the Zenodo repository (Österman et al. 2026a, https://doi.org/10.5281/zenodo.21908280). The data includes the complete data of all brachycyrtine specimens examined by us, basic data of all known Afrotropical specimens, and a character matrix with the diagnostic characters of all Neotropical and Afrotropical species.