Andrena (Aciandrena) equus, WOOD, 2024

WOOD, T. J., 2024, Further revisions to the Palaearctic Andrena fauna (Hymenoptera: Andrenidae), Zootaxa 5483 (1), pp. 1-150 : 81-84

Andrena (Aciandrena) equus spec. nov.

Figures 53A–F ; 54A–F .

HOLOTYPE: TURKEY: Muradiye env., 2000m, 120 km NE Van [inferred 39.0106 oN, 43.7193 oE], 5.vi.2001, ♀, leg. K. Deneš, OÖLM.

PARATYPES: TURKEY: same information as holotype, ♀, TJWC ; Ercek [Erçek]/ Van, 9.vi.1977, 1♂, leg. K. Warncke, OÖLM ; Yüksekova / Hakkâri, 8.vi.1977, 1♀, leg. K. Warncke, OÖLM .

Description: Female: Body length: 5–5.5 mm ( Figure 53A ). Head: Dark, 1.1 times wider than long ( Figure 53B ). Clypeus flattened over majority of surface, irregularly punctate with punctures of variable size, punctures separated by 0.5–2 puncture diameters, underlying surface shagreened in basal ⅔–¾, becoming shiny only in apical ⅓–¼ ( Figure 53C ). Process of labrum broad trapezoidal, 2 times wider than long, anterior margin ½ length of hind margin, straight to slightly emarginate, surface more or less shining. Gena equalling width of compound eye; ocelloccipital distance ½ dimeter of lateral ocellus. Foveae dorsally narrow, occupying ½ space between compound eye and lateral ocellus, ventrally narrowing, almost linear, narrower than the width of the flagellum and separated from inner margin of compound eye by a distance equal to its own width; foveae filled with white hairs. Face, gena, vertex, and scape covered with short whitish hairs. Antennae basally dark, A6–12 ventrally lightened by presence of orange scales; A3 exceeding A4, slightly shorter than A4+5.

Mesosoma: Scutum and scutellum with strong granular shagreen, weakly shining, regularly punctate with small punctures, punctures separated by 0.5–2 puncture diameters ( Figure 53D ). Pronotum rounded. Mesepisternum and dorsolateral parts of propodeum with fine granular shagreen, weakly shining. Propodeal triangle covered with slightly coarser granular shagreen, joining and merging with short raised rugae basally, surface weakly shining; propodeal triangle thus defined by change in surface sculpture ( Figure 53E ). Mesepisternum with moderately long whitish hairs, becoming shorter and sub-squamous on scutum and scutellum. Propodeal corbicula incomplete, weakly formed, dorsal fringe composed of sparse whitish plumose hairs, internal surface with scattered simple white hairs. Legs dark, apical tarsal segments lightened orange, pubescence whitish. Flocculus incomplete, composed of white plumose hairs; femoral and tibial scopae composed of white simple hairs. Hind tarsal claws without inner tooth. Wings hyaline, stigma and venation orange, nervulus antefurcal.

Metasoma: Tergal discs dark, tergal margins lightened dark brown ( Figure 53F ). Tergal discs microreticulate, sculpture strongest basally, dull, becoming weaker apically, here weakly shining. Discs of T1–2 and marginal area of T1 impunctate; discs of T3–4 and marginal areas of T2–4 finely but distinctly punctate, punctures separated by 0.5–1 puncture diameters. Tergal discs laterally with short white hairs, T2–4 apically with weak hairbands, widely separated on T2–3, complete on T4, not obscuring underlying surface. Apical fringe of T5 and hairs flanking pygidial plate golden-white. Pygidial plate narrow, rounded triangular, surface flattened, obscurely punctate, dull.

Male: Body length: 5 mm ( Figure 54A ). Head: Dark, 1.1 times wider than long ( Figure 54B ). Clypeus flattened over majority of area, surface irregularly punctate, punctures separated by 0.5–2 puncture diameters, underlying surface shagreened, weakly shining. Process of labrum rounded trapezoidal, slightly wider than long. Gena subequal to width of compound eye; ocelloccipital distance ⅔ diameter of lateral ocellus. Face, gena, vertex, and scape with white hairs, none equalling length of scape. Antennae basally dark, A5–13 ventrally lightened by presence of grey scales; A3 slightly longer than A4, shorter than A4+5.

Mesosoma: Mesosoma structurally as in female ( Figures 54C–D ), covered with white hairs, hind tarsal claws with strong inner tooth.

Metasoma: Terga structurally as in female, though tergal punctation present also on discs of T1–2 (Figure 54E). T6–7 with short whitish hairs overlying pygidial plate of T7. S8 short, apically broadened with truncate apex, ventrally covered by short whitish hairs. Genital capsule compact, gonocoxae produced into long, apically rounded teeth ( Figure 54F ). Gonostyli broadened and spatulate apically, inner margin raised, outer margin forming more or less rounded 90 o angle. Penis valves basally relatively broad, occupying ½ space between gonostyli, strongly narrowing apically.

Diagnosis. Andrena equus can be recognised as an Aciandrena due to the small body size, propodeal triangle not defined by lateral carinae ( Figure 53E ), surface covered by fine granular shagreen, with weak and obscure rugae basally, facial foveae narrower ventrally than dorsally, approaching a linear state and thus similar to the former Distandrena (= Micrandrena ) but the clypeus, supraclypeal and lower paraocular areas are free of striations, the yellow male clypeus ( Figure 54B ), the small and compact genital capsule with produced gonocoxal teeth ( Figure 54F ), and the female hind tibial claws lack an inner tooth. Within the Aciandrena , it can be recognised most clearly due to the finely but distinctly punctate terga (with the exception of T1), with punctures extending onto the tergal margins ( Figures 53F ; 54E ). The only comparable Aciandrena species is A. fulica Warncke, 1974 which is restricted to the Western Mediterranean ( Portugal, Spain, Morocco, Algeria, Tunisia; Wood et al. 2020b; Wood 2023b). Andrena fulica can be separated as T1 (both disc and margin) have obscure punctures, the marginal areas of T2–4 are strongly and distinctly depressed and more broadly lightened hyaline-brown (in A. equus with only the apical rim of the tergal margins lightened brown), and the head is 1.4 times wider than long (in A. equus with the head 1.1 times wider than long). This relatively elongate head in A. equus ( Figures 53B ; 54B ) is useful for separation from similar Aciandrena species; in almost all other Aciandrena species it is broader, typically 1.2–1.4 times wider than long. Although this character is not immediately diagnostic due to the requirement for measurement, it can be useful to separate out species with clearly shorter heads that occur in Turkey such as A. aciculata Morawitz, 1886 and A. tenuis Morawitz, 1877 .

Etymology. The nominative singular form of the Latin equus meaning horse, in reference to the relatively long face of this Aciandrena species. It is a noun in apposition.

Distribution. Eastern Turkey (provinces of Hakkâri and Van).

Figures

FIGURE 53. Andrena (Aciandrena) equus spec. nov. female. A. Habitus, lateral view; B. Face, frontal view; C. Process of labrum, ventral view; D. Scutum, dorsal view; E. Propodeum, dorsal view; F. Terga, dorsal view.

FIGURE 54. Andrena (Aciandrena) equus spec. nov. male. A. Habitus, lateral view; B. Face, frontal view; C. Scutum, dorsal view; D. Propodeum, dorsal view; E. Terga, dorsal view; F. Genital capsule, dorsal view.