We examined a series of Dasypoda (Heterodasypoda) specimens collected in southern Portugal in the years 2005–2006 by M. and E. Howe, following the taxonomic key from Michez et al. (2004a). The morphological characteristics of two females could be identified as those of Heterodasypoda but did not correspond to any previously known Dasypoda species (following Michez et al. 2004a), while the males could be determined as Dasypoda michezi Radchenko following the detailed description provided by Radchenko (2017).

We sequenced a fragment of the cytochrome oxidase I (COI) gene from these two female specimens and from sympatric males of Dasypoda michezi. DNA was extracted from a middle leg of every individual using the Nucleo spin Tissue kit (Macherey-Nagel, Germany) following manufacturer instructions with a lower volume of elution buffer and expanded final incubation times to improve DNA yield. As pinned specimens from old collections (>10 years) can be difficult to sequence (i.e. their DNA has degraded over time and moreover is affected by the different processes of preservation of the collections), it is advisable to amplify small amplicons (<200 bp) (Wandeler et al. 2007). Therefore, modified LEP primers for older samples (LEP-F1/LEP-R2, Hebert et al. 2004) were selected to amplify a fragment of the cytochrome oxidase subunit 1 (COI) gene, a region commonly used to study the taxonomic status of animals, and frequently used in bee taxonomy (e.g. Orr et al. 2018; Weissmann et al. 2018; Ghisbain et al. 2020a). After Sanger sequencing (Eurofins Genomics, Spain) and alignment of the cleaned sequences, we ran a neighbor-joining phylogeny with 10,000 bootstraps including D. michezi (n = 7, including the two female specimens) along with representatives of each species of Heterodasypoda: D. morotei Quilis, 1928 (n = 2), D. pyrotrichia Förster, 1855 (n = 1), D. albimana Pérez, 1905 (n = 3). We chose the slightly more distant Dasypoda (Microdasypoda) crassicornis Friese, 1896 as an outgroup.

Based on the results of the genetic barcoding (see below), we further examined the morphology of these females in comparison with that of the males and that of the other species of Heterodasypoda (i.e. Dasypoda albimana, D. morotei and D. pyrotrichia). High-quality pictures of both sexes of D. michezi were taken using a Canon EOS 5DS R (Canon Inc., Tokyo, Japan) camera assembled onto a stereomicroscope Leica M205C (Leica Microsystems, Wetzlar, Germany) with Leica LED5000 HDI illuminator under Helicon Remote 3.9.7.w. software. Photographs were then combined into a single image using Helicon Focus 7.5.6 Pro (Helicon Soft Ltd, Kharkiv, Ukraine) automontage software.

Finally, we established a key to all known species of Heterodasypoda following Michez et al. (2004a, b) and the results of the present study. The following abbreviations, after Michener (2007), are used below: T1, T2… = first, second, etc. metasomal terga; S1, S2… = first, second, etc. metasomal sterna; A1, A2… = first, second, etc. antennal segments, pw = puncture width.

We assessed an IUCN status for Dasypoda michezi following the Guidelines for using the IUCN Red List Categories and Criteria V. 14 (https://www.iucnredlist.org/resources/redlistguidelines) and the protocol of Nieto et al. (2014). To do so, we measured both the area of occupancy (AOO) and extent of occurrence (EOO) of the species. The AOO is the measure of the area in which a species occurs and corresponds to the sum of the area of grids the species occupies, while the EOO is a measure of the geographic range size of a species and is calculated by drawing a convex hull which is defined as the smallest polygon containing all the sites of occurrence and in which no internal angle exceeds 180 °C.

The amplified COI fragment of the examined male and female specimens of Heterodasypoda collected in southern Portugal were identical, and distinct from all other species of Heterodasypoda (Fig. 1A). Given that the males morphologically correspond to the original description of Dasypoda (Heterodasypoda) michezi from Radchenko (2017), we can state with confidence that the examined females belong to D. michezi. Updated maps of the Western-Mediterranean distributions of the four known species of Heterodasypoda are given in Figure 1B, C. New sequences are available on Genbank with the accession numbers MW389319–MW389326; MW401790–MW401795.

Figure 1. 

A COI phylogeny of the Heterodasypoda, highlighting the association of both female and male specimens of D. michezi from southern Portugal, with D. (Microdasypoda) crassicornis as an outgroup B, C West Mediterranean distribution of the four known species of Heterodasypoda: B records of D. albimana (orange) and D. michezi (red, new records indicated by the black arrow) C records of D. morotei (green) and D. pyrotrichia (blue). Adapted from Michez et al. (2004) and Radchenko (2017).

First description of the females of Dasypoda michezi

Figures 2–14

Note. We describe for the first time the female of Dasypoda michezi. Specimens examined during the study are deposited in the entomological collection of the Laboratory of Zoology of the University of Mons (Belgium) and in the Institute for Evolutionary Ecology of the National Academy of Sciences of Ukraine.

Material examined. 2 ♀♀, Portugal, Algarve, Sagres Camp/Heath [37.0249°N, 8.9463°W], 13.IV.2006, leg. M. and E. Howe.

Description. Female (Figs 2–15). Body length = 13.5–13.6 mm. Head (Figs 4–9). W – 3. 55–3.65 mm; H – 3.23–3.25 mm. Face between antennae dull, densely punctured and bearing erect white and dark (brown-black) hairs, proportion of dark hairs greater on lateral parts of face and just below ocellar field. Area in front of ocellae very densely punctured and matt, this puncturing less dense behind ocellar field. Area between lateral ocellae and compound eyes shagreened. Vertex (Fig. 5) with sparse yellow pilosity and dark erect setae. Clypeus densely punctured, punctures less than 1 pw apart, on most of its surface, punctures slightly larger and more separated distally. Medio-distal part of clypeus shiny; distal part with tufts of short white hair mixed with a few darker setae; hairless medially except in some areas with a few white and black setae; basal and lateral parts covered with mixed white and black hairs. Labrum unpunctured and shiny basally; distal part bearing thick orange setae inserted in large punctures. Mandibles black, in some places with dark red shades, bearing long white setae ventrally. Malar space (Fig. 6) shorter than width of mandible at its base, one specimen bearing very short, thick, white, black pilosity. Maxillary palpus and galea subequal. Galea with small tubercles merged into sinuous lines on most of its surface; margin of galea with bristles all along its length (Fig. 8). Glossa dark with yellow apical bristles. Maxillary palpi approximately 0.75 times as long as length of glossa (Fig. 9). Scape with sparse dark or white setae; surface shiny, sparsely punctate, punctures large. Last article of antennae truncated at apex (Fig. 7).

Figures 2–14. 

Female of D. michezi from Algarve, southern Portugal (first description) 2 dorsal view 3 lateral view 4 head (frontal view) 5 vertex and ocelli 6 malar area 7 flagellum and pedicel 8 galea and maxillary palpus 9 glossa and labial palpus inside the galea (ventral view) 10 scutum 11 metanotum and propodeum 12 metasoma (dorsal view) 13 pygidial plate 14 metasoma (ventral view).

Mesosoma (Figs 10, 11). W (between tegulae) – 3.15–3.24 mm. Scutum densely punctured medially (Fig. 10), shagreened between punctures, shiny in center, but matt laterally. Small unpunctured, shiny area in center of scutum with starting point of clearly visible carina extending to the most distal part of scutum. Parapsidal lines very thin and long. Scutum with sparse dark pilosity medially, surrounding parts bearing erect dark and yellowish pilosity, proportion of yellowish hairs greater laterally. Scutellum, metanotum and propodeum (Fig. 11) densely punctured and matt, scutellum bearing a majority of erect dark hairs; metanotum and propodeum mostly with yellowish erect setae. Mesosoma ventrally with dense pure-white pilosity ventrally. Tegulae dark brown, slightly shagreened and shiny. Wings transparent, slightly darkened (Figs 2, 3, 15). Forelegs bearing long brown hairs dorsally, protibia and probasitarsus with short orange pilosity ventrally. Mesotibia with yellowish-whitish pilosity ventrally and brown pilosity dorsally. Mesobasitarsus with orange pilosity ventrally, brown pilosity dorsally and whitish pilosity on its outer face. Metatibia and metabasitarsus with whitish pilosity ventrally and brown pilosity dorsally, metabasitarsus bearing orange pilosity on its posterior surface.

Metasoma (Figs 12–14). L – 7.7–7.8 mm; W (at widest point) – 4–4.5 mm. T1 evenly punctate, surface matt, pilosity as on metanotum and propodeum. T2–T4 matt and strongly shagreened, bearing whitish tufts of hair laterally, with very sparse brown pilosity on discs. T5 with denser and longer erect dark pilosity, except lateral part with whitish pilosity as on other terga. Punctures of T5 strong, dense, less than 1 pw apart laterally, but approx. 1 pw medially. Sides of T6 (around pygidial plate) bearing the same dense and long dark pilosity as on T5. Pygidial plate (Fig. 13) hairless, depressed, dark purple, narrowly elongate and bifurcate apically. Sterna thinly shagreened anteriorly with short brown pilosity, strongly punctured posteriorly (Fig. 14).

Additional male material examined. Portugal, Algarve, Sagres Camp/Heath [37.0249°N, 8.9463°W], leg. M and E Howe, 3.IV.2005 (2 ♂♂) , 4.IV.2005 (3 ♂♂), 7.IV.2005 (1 ♂) 13.IV.2006 (1 ♂), at the same place and same day as the presently described females); 1 ♂, Portugal, Algarve, Sagres Campsite [same locality, 37.0249°N, 8.9463°W], 10.IV.2006, leg. M and E Howe; 1 ♂, Portugal, Algarve, Cabo de Sao Vicente [37.0227°N, 8.9964°W], 11.IV.2006, leg. M and E Howe. All specimens are deposited in the Laboratory of Zoology (UMons, Belgium).

Phenology and ecology. Flight period. The previous records of D. michezi were in late spring (20^th–21^st May) (Radchenko 2017). Our new records are from earlier in the season (3^rd–13^th April).

Floral choices. Unfortunately, the labels of the newly recorded specimens do not carry floral records. Some labels state “Heath”, which may refer to the type of vegetation at the collecting sites and not the visited plant (Erica).

Females

Males

Detailed diagnosis of the males of Heterodasypoda is available in Radchenko (2017) and new pictures of are provided in Figures 22–36.

Figures 15–21. 

Comparison of the mesotibia pubescence between D. michezi and D. morotei 15 female of D. michezi (fronto-lateral view; the position of the mesotibia is the same as in Fig. 16) 16–18 pubescence of D. michezi mesotibia under different magnifications 19–21 Pubescence of D. morotei mesotibia under different magnifications.

Figures 22–36. 

Male of D. michezi from Algarve, southern Portugal 22 dorsal view 23 lateral view 24 head (frontal view) 25 vertex and ocelli 26 malar area 27 antenna 28 galea and maxillary palpus 29 glossa and labial palpus (dorsal view) 30 scutum 31 propodeum 32 metasoma (dorsal view) 33 metasoma (ventral view) 34 S6-8 and genitalia (ventral view) 35 genitalia (lateral view) 36 genitalia (dorsal view).

The known EOO of Dasypoda michezi based on all available records encompasses ~199 km² while its known AOO encompasses 16 km² (based on 2 km × 2 km cell width). Both these measures are associated with the category Endangered following the IUCN criteria B1 and B2 and their combination with the condition “a” ([Extent/Habitat] severely fragmented OR [low] number of locations) since the bee has only been reported from a very small number of locations. We therefore assess the IUCN Red List criteria of D. michezi as Endangered with the code B1a+B2a (see discussion).

The female of D. michezi presents some singular morphological features compared to the rest of the Heterodasypoda species, including a clear differentiation in its color pattern from the morphologically closely related D. albimana, the most visible being the color of the pilosity of the mid-leg (white in D. albimana and dark brown dorsally in D. michezi). The species confirms the original combination of morphological characteristics of the female sex proposed by Michez et al. (2004) for the subgenus, namely (i) a clypeus entirely punctured with or without a median carina, (ii) a scopa bicolored, (iii) the disc of T2 with a rather straight marginal line, (iv) pygidial plate glabrous, (v) maxillary palpae and galea of a subequal length, (vi) the margin of the galea with setae along its entire length, (vii) a malar space shorter than the length of the pedicel and (viii) a prefurcal nervulus.

In a context of global declines in bee populations (Potts et al. 2010), the restricted distribution of Dasypoda michezi in the south of Portugal ultimately raises questions about its conservation. Having a restricted distribution implies that, if they occur, all or most individuals will experience adverse conditions simultaneously (Gaston 1998) and, because endemic species present by definition a few sites for conservation intervention, they are inherently more vulnerable to extinction in a context of global changes, particularly climate and habitat change. Moreover, the very recent description of the species (in 2017) naturally means that it was not attributed to a conservation status in the Red List of European bees (Nieto et al. 2014). In the latter work, the subfamily Dasypodainae was amongst the most at risk with 25% of its species being threatened. The IUCN status assessed here, Endangered with the code B1a + B2a, closely recalls those of the other threatened Dasypoda that were all assessed at least with the criterion B2a (accompanied with b[iii]), a threat related to a combination of an overall small AOO, severely fragmented habitats or a low number of locations, and a continuous decline estimated for the quality of the habitat. These criteria are shared with a large number of other threatened bees in Europe (Nieto et al. 2014), highlighting the need to preserve the most suitable natural habitats for the bee fauna of the continent (Michez et al. 2019; Ghisbain et al. 2020b). The criterion b(iii), associated with a continuous decline of habitat quality, is not appropriate for the status of D. michezi given that the whole known distribution of the species is included in a protected area, the Parque Natural do Sudoeste Alentejano e Costa Vicentina. Long-term preservation of such protected habitats is especially critical for bees like Dasypoda due to their relatively specialized foraging behaviour (Michez et al. 2008), a characteristic that could make them especially susceptible to changes in their environment as they do not switch to alternative host plants (Scheper et al. 2014). Dasypoda bees rely on flower-rich environments, and the subgenus Heterodasypoda is mostly associated with Cistaceae and Asteraceae (Michez et al. 2004b, 2008; Ruiz 2013; Özbek 2014) with other records on Lamiaceae and Rosaceae (Michez et al. 2003, 2004b; Ruiz 2013). Radchenko (2017) highlights the association of the males of D. michezi with Cistus (Cistaceae) pollen, which is consistent with the floral choices of other representatives of the subgenus. Further work is needed to characterize in more detail the floral choices of Dasypoda michezi in this National Park and to estimate the population trends of its host plants in its restricted range. With global warming and its associated higher intensity of extreme weather events, such a monitoring of habitat quality is crucial in areas like southern Portugal where heat waves and fires are already frequent.

In addition to the need to characterize the habitats in which D. michezi occurs, more observations of the species are also required to precisely delineate the timing of its flight period. Heterodasypoda bees are known to fly from late spring to late summer: May-July for D. albimana (Michez et al. 2003), mostly May-August for D. morotei and D. pyrotrichia (Ornosa and Ortiz-Sánchez 1998, 2004; Grace 2010). Our new records combined with those of Radchenko (2017) suggest that the flight period of Dasypoda michezi encompasses April and May (late spring). Overall, given the growing evidence that significant phenological shifts and mismatches in plant-pollinator interactions following global warming are occurring (Duchenne et al. 2020; Gérard et al. 2020), further understanding the species phenology and floral associations during their flight period is a key to their effective conservation.

Although Europe constitutes one of the most extensively studied areas in the world for bees (Michez et al. 2019), the very recent discovery and characterization of Dasypoda michezi in Portugal is not surprising. New bee species are still continuously described from the Iberian Peninsula (Müller 2012; Wood and Cross 2017; Kuhlmann and Smit 2018; Smit 2018; Wood et al. 2020a), a geographic area that constitutes a global hotspot not only for bee species diversity (Orr et al. 2020) but also for many other organisms (Gómez and Lunt 2007). In total, over 1000 bee species are known from Spain (Ortiz-Sánchez 2011, 2020) and 722 from Portugal (Baldock et al. 2018; Wood et al. 2020a). This high diversity is partly due to the role that the Peninsula played as a glacial refugium during the Quaternary (Hewitt 2011), as well as the Mediterranean climate of the region, combined with the striking diversity of habitats (i.e. a combination of meadows, scrublands, mountains, woodlands and coastlines). In particular, the Iberian Peninsula constitutes a center of diversity for both of the Dasypoda subgenera Microdasypoda and Heterodasypoda. The first subgenus includes four known species, with one species endemic to Iberia: D. iberica (Michez et al. 2004b; Radchenko et al. 2019). The second includes four species with two endemics: the currently studied D. michezi and also D. morotei (Michez et al. 2004b; Radchenko 2017). Despite the extremely rich bee diversity of the Iberian Peninsula however, both Spain and Portugal present a very high percentage of species assessed as “data deficient” in the European Red List (Nieto et al. 2014; Wood et al. 2020b). The present case further suggests that additional efforts are encouraged to characterize and monitor the highly diverse bee fauna of these understudied areas. Future projects that focus on understanding the ecology of endemic bee species and delineating more precisely their distributions are encouraged to assess the potential threats that these species could face in the near future.