Revision of New World Helava Masner & Huggert ( Platygastridae , Sceliotrachelinae )

Nine new species of Helava are described: H. acutiventris sp. n., H. allomera sp. n., H. aureipes sp. n., H. carinata sp. n., H. microptera sp. n., H. pygmea sp. n., H. reducta sp. n., H. simplex sp. n., and H. samanthae sp. n., and Helava alticola Masner & Huggert is redescribed. New characters are presented to supplement the generic description of Masner and Huggert (1989) and the genus is diagnosed from similar genera in Sceliotrachelinae: Aphanomerus Dodd and Austromerus Masner & Huggert.


Introduction
Helava was described by Masner and Huggert in their 1989 treatment of world genera of Sceliotrachelinae.Masner and Huggert separated Helava from Austromerus on the basis of "clavate" antennae in males.We here replace "clavate" with the term "clubbed" to describe the apically enlarged antennomeres in males to maintain strict use of terminology in which clavomeres are defined by the presence of basiconic sensilla.Our revision of Helava reveals that the male antenna is filiform in two species, H. acutiventris and H. allomera, and thus Helava and Austromerus are separable only by the form of the clava in females: compact in Helava and with articulated clavomeres in Austromerus (compare Figures 2 and 12; see also figures 168-173 in Masner and Huggert (1989)).Helava is also morphologically very close to Aphanomerus, from which Masner and Huggert (1989) separated Helava by the dense setation on T1-T2 and presence of propodeal foamy structures (compare Figures 1 and 20).In the concept of Masner and Huggert (1989), Helava is found in South America, Tasmania and continental Australia, a distribution consistent with a Gondwanan origin.The limits of Helava, Aphanomerus and Austromerus have become blurred following this revision and testing hypotheses about the phylogeography of the genus will require a better understanding of relationships between these three genera.We refrain from describing the Australian species of Helava until species-level revision of Aphanomerus and Austromerus are conducted to provide a full grasp of the morphological diversity of their constituent species.Currently no host data are known for Helava.

Materials and methods
The numbers prefixed with "CNC" or "OSUC " are unique identifiers for the individual specimens (note the blank space after some acronyms).Details of the data associated with these specimens may be accessed at the following link: http://purl.oclc.org/NET/hymenoptera/hol, and entering the identifier in the form.Persistent URIs for each taxonomic concept were minted by xBio:D in accordance with best practices recommended by Hagedorn et al. (2013).Morphological terms were matched to concepts in the Hymenoptera Anatomy Ontology (Yoder et al. 2010) using the text analyzer function.A table of morphological terms and URI links is provided in Suppl.material 1.
Photographs were captured with a Z16 Leica lens with a JVC KY-F75U digital camera using Cartograph software.Single montage images were produced from image stacks with the program CombineZP.In some cases, multiple montage images were stitched together in Photoshop to produce larger images at high resolution and magnification.Full resolution images are archived at the image database at The Ohio State University (http://purl.oclc.org/NET/hymenoptera/specimage).
Scanning electron micrographs were produced with a Hitachi TM300 Tabletop Microscope.The specimen was disarticulated with a minuten probe and forceps and mounted on 12 mm slotted aluminum mounting stub (EMS Cat.#75220) using carbon adhesive tabs (EMS Cat.#77825-12) by means of a fine paint brush and sputter coated with approximately 70 nm of gold/palladium.This work is based on specimens deposited in the following repositories with abbreviations used in the text:

Diagnosis of Helava
In the process of coding characters for potential use in species delimitation we encountered a small number of new characters shared between all New World species of Helava.We here present a generic diagnosis based on these characters and those presented by Masner and Huggert (1989): Antennal formula 10-10.Clava compact in females.Epomium absent.Fore wing with tubular submarginal vein terminating in a truncate knob.Ventral rim of pronotum forming lamella flanking procoxa.Mesopleural carina absent.Setation of axillar area present.Setation of mesoscutellum along posterior and lateral margins dense.1st trochanter longest, particularly on metatrochanter.Setation of coxae dense.Tibial spur formula 1-2-2.Setation of laterotergites present.Sculpture of tergites absent.T2 with narrow strip of dense setation along anterior margin.Sculpture of sternites absent.Felt fields on S2 present.

Key to species (males and females)
1 Foamy structures on lateral propodeum covering area larger than visible part of metapleuron (Figures 9,16,19,29,50)   Diagnosis.The ventral protrusion of S2 in H. acutiventris separates this species from all other species in Helava.In addition to the shape S2, the absence of a transepisternal line on the mesopleuron is shared only with H. reducta, which is a starkly different species that can be separated by the absence of ocelli and a scutoscutellar sulcus.
Etymology.The epithet "acutiventris" is given to this species in reference to the sharp projection on S2 in both sexes.
Link Comments.The diagnostic shape of S2 is found in both males and females, leading us to believe that this is not an adaptation for housing the retracted ovipositor system, as can be found in some species of Synopeas Förster and Platygaster Latreille.Diagnosis.Helava allomera can be differentiated from other species in the genus by the combination of the well-developed hyperoccipital carina, percurrent notauli, and foamy structures on the propodeum that are larger than the visible part of the metapleuron in lateral view.Within Helava, this is the only species with a dorsoventral band of dense setae along the posterior margin of the lateral pronotum (Figure 9).

Helava allomera
Etymology.The epithet "allomera" is given to this species in reference to the unusual form and segmentation of antennae in both sexes.

Helava aureipes
Etymology.The epithet "aureipes" is given to this species in reference to the golden colour of the legs.
Link    Diagnosis.Helava carinata belongs to the cluster of species with large propodeal foamy structures that includes H. alticola, H. allomera, and H. samanthae.It can be separated from H. alticola and H. samanthae by the setation of the upper frons and posterior vertex, which is either absent or very sparse.In H. alticola the upper frons is glabrous or nearly so, and then abruptly setose posterior to the ocelli; the dorsal head in H. samanthae is setose throughout.Helava carinata can be separated from H. allomera by the absence of dense setation on the posterior part of the lateral pronotum (compare Figures 9 and 29).

Helava microptera
Etymology.The Greek name "microptera" refers to the small size of the wings in males and females of this species.Diagnosis.Helava pygmea is closest to H. simplex, with which it shares the presence of small propodeal foamy structures, fully developed wings, and a mesoscutum without notauli.The only character that reliably separates these species is the form of the basal vein (Rs+M) in the fore wing: darkly pigmented in H. pygmea and absent in H. simplex.
Etymology.The species name "pygmea" refers to the small size of the body in this species.