Andrena (Orandrena) densissima, Wood, 2021

Wood, Thomas James, 2021, Fifteen new Andrena species from little-visited arid, Mediterranean, and mountainous parts of the Old World (Hymenoptera: Andrenidae), Zootaxa 4933 (4), pp. 451-492 : 479-480

Andrena (Orandrena) densissima spec. nov.

urn:lsid:zoobank.org:act:BEA79392-12BB-4796-872A-8CDD9C876A4A

HOLOTYPE: TUNISIA: Ksar Hadada , 4–5.iv.1996, 1♀, leg. K. Deneš ( OÖLM).

Description: Female: Body length 8 mm ( Figure 95 ). Head: Black, 1.1 times wider than long. Clypeus weakly domed, shallowly and irregularly punctate, punctures separated by 0.5–3 puncture diameters; narrow longitudinal impunctate central line present, underlying surface strongly microreticulate, dull ( Figure 96 ). Process of labrum short and wide, apically evenly rounded, dorsal surface microreticulate, dull. Gena subequal to width of compound eye; ocelloccipital distance equals ½ width of lateral ocellus. Fovea dorsally occupying ½ distance between lateral ocellus and compound eye, strongly narrowed ventrally, narrower than width of flagellum. Gena, vertex, face, and scape with long whitish to yellowish hairs, longest equalling length of scape. Antenna dark, A4 apically, A5–12 lightened orange below, A3 exceeds A4+5, shorter than A4+5+6. Mesosoma: Scutum and scutellum irregularly punctate, punctures separated by 0.5–3 puncture diameters, underlying surface shagreened, weakly shining ( Figure 97 ). Pronotum rounded, without humeral angle. Episternum and lateral and dorsolateral parts of propodeum shallowly punctate with large punctures, separated by 0.5–1 puncture diameter, underlying surface shagreened, weakly shining, propodeal triangle indicated by change in sculpturing, internal area finely shagreened with weak central rugosity. Episternum and propodeum with long whitish hairs, scutum and scutellum almost hairless, laterally with short sparse light brownish hairs. Legs dark, apical tarsal segments lightened brown, pubescence white, scopa white; hind face of hind femur with 6 strongly produced semi-translucent orange pointed spines, clearly projecting perpendicularly ( Figure 98 ). Wings hyaline, venation and stigma orange, nervulus interstitial. Metasoma: Tergal discs dark, apical margins occupying 2/5ths to ½ visible area, lightened orange-yellow, hyaline ( Figure 99 ), sterna lightened dark orange-red. Terga regularly but superficially punctate, punctures separated by 1 puncture diameter; underlying surface of T1 smooth and shining, T2–4 shagreened, weakly shining. T1–4 with thick, long apical hair bands that obscure underlying surface, widely interrupted on T1–2, continuous on T3–4, apical fringe of T5 and hairs flanking pygidial plate golden; pygidial plate triangular, apex pointed, dorsal surface apically weakly domed, impunctate.

Male: Unknown.

Diagnosis: The subgenus Orandrena is easily recognised in the female sex by the combination of pronounced spines on the hind face of the hind femur, simple scopal hairs, and foveae that are strongly narrowed ventrally. Note, this subgenus should exclude A. garrula Warncke, 1965 which falls outside the true Orandrena ( Pisanty et al. 2020) and which can easily be separated in the female sex by its lack of large punctures on the episternum. With the exception of A. pela Warncke, 1974 from Morocco that is easily separated by its strongly depressed tergal margins, female Orandrena fall into two groups: those with a dull clypeus ( A. monilia Warncke, 1967 ), and the remaining five species ( Table 2) that have clypei with clear longitudinal striations. Andrena densissima has a dull clypeus without striations, placing it close to A. monilia , but it can be easily separated ( A. monilia character state in parentheses) by the process of the labrum which is wide, short, and shallowly rounded, not forming a clear apical point (forming a clear triangular point), by its smaller size of 8 mm (larger, 10–11 mm), by the shagreened and only weakly shining scutum (scutum with very weak shagreenation, shining. Note, this only applies to western A. monilia populations from Spain to Tunisia. Eastern populations in Israel and Jordan have similarly shagreened scuta; these populations may deserve species status in future revisions), and by the much wider tergal hair bands that clearly exceed the width of the tergal margins (hairbands not clearly exceeding the width of the tergal margins, Figures 99–100 ).

Discussion: As a subgenus, Orandrena shows a Mediterranean distribution, but individual species have strongly restricted distributions, most notably those found in Turkey which is the clear centre of diversity, most of which were described by Warncke ( Table 2). The exception to this rule is A. monilia which is found across the Mediterranean basin, though it is variable throughout this range, and populations in the Middle East potentially deserve species status because of variation in integumental sculpturing and male clypeal colouration. Andrena monilia was reported from the northern part of Tunisia some years after its original description ( Warncke 1980), and its presence in the country can be confirmed by more recently examined material (see below). In contrast, A. densissima was collected from southern Tunisia and clearly differs morphologically. Like most members of the subgenus, it may have a highly restricted range, and similar desert habitats in Algeria and Libya should be searched to see if it is more widespread in these regions.

Etymology: The name is the feminine superlative degree of denso (dense, thick, therefore very dense, very thick) because of the pronounced hair bands in the female sex that set it apart from other Orandrena species.

Other material examined: ( Andrena monilia ): ISRAEL: Mishmar HaNegev , 24.iii.19xx [year unspecified], 1♀, leg. Bytinski-Salz, ZMHB ; Gal’on , 23.iii.2010, 1♀, leg. G. Pisanty, SMNHTAU ; JORDAN: 30 km N Tafila [ At-Tafilah ], 2.v.1996, 4♀, leg. Ma. Halada, OÖLM ; Al Karak env [Kerak], 6.iv.2013, 1³, 1♀, leg. M. Snižek, OÖLM ; TUNISIA: Kasserine, 13.iv.1998, 2³, leg. K. Deneš, OÖLM ; Sbeitla , 12.iv.1998, 1♀, leg. K. Deneš, OÖLM ; SPAIN: Montarco , 10.v.1933, 1♀, leg. J. M. Dusmet y Alonso, OÖLM (holotype, Figure 100 ) ; Montarco , 28.iv.1924, 1³, leg. J. M. Dusmet y Alonso, OÖLM (paratype).

Figures

FIGURES 95–100. Andrena densissima spec. nov. 95. female profile, 96. female face, 97. female scutum, 98. female hind femur; 99. female terga. Andrena monilia Warncke, 1967 (holotype); 100. female terga.