Perdita (Perdita) islacabritosensis, Ascher & Engel, 2012

Ascher, John S. & Engel, Michael S., 2012, Discovery of the bee genus Perdita in the West Indies (Hymenoptera: Andrenidae): a new species from Isla Cabritos in the Dominican Republic, Acta Entomologica Musei Nationalis Pragae 52 (2), pp. 595-602 : 596-599

Perdita (Perdita) islacabritosensis sp. nov.

( Figs. 1–4 )

Type material. HOLOTYPE: J, Isla Cabrito [= Isla Cabritos or Little Goat Island], Descubierta, Prov. Independencia, R.D. [ República Dominicana], 7-vii-1979 [7 July 1979], col. Marcano ( SEMC) . PARATYPE: J, same as that of the holotype ( MHND).

Diagnosis. The new species is superficially similar to Perdita (Perdita) stottleri Cockerell, 1896 and will run to this species in TIMBERLAKE’ s (1958) key to the zonalis species group but differs in its facial maculation ( Fig. 3 ; cf. COCKERELL 1896) and its noticeably smaller size (length around 6 mm in P. stottleri vs. about 4.5 mm in the new species). The species share the presence of yellow anteriorly on the mesosternum and completely yellow face below the level of the antennae, the finely and even faintly imbricate (= evanescent tessellation sensu Timberlake) integument of the mesoscutum, and the shorter mandibles which extend at most to the far side of the proboscidial fossa. Such characters are perhaps not indicative of genealogical relationship and considerable phylogenetic work is needed in Perdita (Perdita) (vide Discussion, infra).

Description. Male. Total body length 4.42 mm (4.25 mm); forewing length 2.92 mm (2.88 mm). Head wider than long, length 1.07 mm (1.01 mm), width 1.35 mm (1.29 mm); mandible simple, not elongate or falcate, extending at most to far margin of proboscidial fossa when closed; gena narrower than compound eye; facial fovea weakly impressed, a little less than one-half median ocellar diameter in width, about twice as long as wide. Pronotum with medial, transverse ridge running laterally into lateral grooves which curve posteriorly anterior of pronotal lobe. Intertegular distance 0.97 mm. Pygidial plate tapering apically to acutely-rounded point.

Integument of head and mesosoma gently and finely imbricate (= evanescent tessellation sensu Timberlake) (consistent with zonalis group); labrum impunctate; clypeus impunctate medially otherwise with small, shallow, and faint punctures separated by 1–2 times a puncture width; supraclypeal area impunctate; face with small, shallow, and faint (only visible under raking light) punctures separated by 1–3 times a puncture width; vertex sculptured as on face, integument shiny; gena as on vertex except punctures more sparse. Pronotum impunctate; mesoscutum with small, shallow, faint punctures separated by 1.5–3.5 times a puncture width; mesoscutellum and metanotum as on mesoscutum although punctures separated by 1–2.5 times a puncture width and imbrication stronger on metanotum; mesepisternum with small, shallow, and faint punctures separated by 2–5 times a puncture width; metepisternum impunctate; basal area of propodeum impunctate ( Fig. 4 ); lateral and posterior surfaces of propodeum impunctate. Metasoma faintly imbricate.

Head dark brown with a blue-green tint except yellow on mandible (red at apex), labrum, clypeus, most of face below level of ocelli as depicted in Fig. 3 (consistent with the zonalis group), and antenna except brown on dorsum of pedicel, flagellomeres I–IV, less so on flagellomeres V–VII, and dorsobasally on flagellomere VIII ( Fig. 2 ). Pronotum yellow with broad transverse band of dark brown with blue-green tint medially ( Fig. 2 ), laterally band not reaching to ventral margin; propleura yellow; mesoscutum dark brown with blue-green tints; tegula light translucent yellow; mesoscutellum and metanotum as on mesoscutum; pleura dark brown with blue-green tints except yellow anteriorly on mesepisternum as depicted in Fig. 1 ; propodeum dark brown with blue-green tint. Legs yellow except brown on posterior surface of metafemur, outer surface of metatibia, and dark brown dorsally on metacoxa. Wing membranes hyaline and clear; veins light yellow brown. Metasomal terga dark brown except extensively marked with yellow to create banded appearance (consistent with the zonalis group); tergum I with yellow laterally and forming a broad band across disc at bend between anterior- and dorsal-facing surfaces, band of yellow only slightly narrower than apical margin of dark brown, anteromedially notched; tergum II–V each with broad medial band of yellow across disc, bands of terga II–IV broader than apical dark brown areas ( Fig. 5 ); pygidial plate brown; sterna yellow except extreme base of sternum I dark brown.

Pubescence typical for males of subgenus Perdita and generally white throughout.

Female. Unknown.

Etymology. The specific epithet is taken from the type locality, Isla Cabritos, Dominican Republic.

Comments. An attempt was made to dissect the material but after considerable time in a humidification chamber the apical metasomal segments were unrelenting and we opted to refrain from further manipulation less the specimen become damaged. It is greatly hoped that extensive sampling of bees in the Dominican Republic might bring forth additional material, including females, so that the species can be more fully characterized and compared with its congeners.

Figures

Fig. 1. Lateral habitus of holotype male of Perdita (Perdita) islacabritosensis sp. nov.

Figs. 2–5. Perdita (Perdita) islacabritosensis sp. nov., male holotype: 2 – dorsal habitus; 3 – facial view; 4 – dorsal detail of base of propodeum; 5 – dorsal view of metasoma.