Geodiscelis (Nazcoediscelis) Packer and Dumesh

Packer, Laurence & Dumesh, Sheila, 2014, Two new species of Geodiscelis Michener & Rozen (Hymenoptera: Apoidea: Colletidae) with a phylogenetic analysis and subgeneric classification of the genus, Zootaxa 3857 (2), pp. 275-291 : 288

Geodiscelis (Nazcoediscelis) Packer and Dumesh , new subgenus

urn:lsid:zoobank.org:act:0249B978-22A9-4919-95D9-A54EE618 DE 33

Type species. Geodiscelis nazcalinea Packer & Dumesh sp. nov. Here designated.

Diagnosis. The combination of metasoma with pale subapical transverse bands, maxillary palpus with all 6 palpomeres similarly robust and malar space at least 3X as long as the basal depth of the mandible is sufficient to identify any colletid bee as belonging to this subgenus. Additionally, the males have S6 obtusely angulate or with a spine apicomedially.

Description. Lower paraocular area black. Male protibia entirely or almost entirely yellow. Metasomal terga with pale subapical integumental bands, basal bands of appressed squamose pubescence present, minute silvery hairs absent. Clypeus and lower paraocular area dull due to imbricate microsculpture. Frontal area with interspaces equal to or greater than puncture diameters. Mesoscutum somewhat shiny, microsculpture imbricate; punctures transversely effaced. Galeal comb teeth absent. Mandible with subapical tooth small to absent. Malar space enormous, at least three time as long as basal depth of mandible. Anterior tentorial pit elongate, almost attaining apex of clypeus. Supraclypeal area mostly flat. Metasternum between metacoxae very narrow, width subequal to MOD. First abscissa of M+Cu of hind wing shorter than 2nd abscissa. Male hindleg unmodified, narrow; both sexes with two metatibial spurs. Horizontal surface of metapostnotum subequal in length to scutellum. Sclerotized portion of proctiger undivided medially. Male S6 with apex angulate or spinose. S7 apicodorsal lobe simple, flat. S8 apical process narrowing to apex; posterior margin of lateral lobe narrowly concave, posterior convexity laterad. Gonobase with apicoventral rim lacking a median process. Gonoforceps with subapical medial angulation. Gonostylus short, narrow; retrorse lobe broad, rounded. Female sternal scopa well developed.

Included species. Geodiscelis longiceps Packer, 2005 , G. nazcalinea Packer & Dumesh , sp. nov. and G. phisquiri Packer & Dumesh sp. nov.

Etymology. The name is derived from that of the type species, which was first found very near to the famous Nazca lines in Peru, combined with Oediscelis.

Comments. This subgenus is known only from west of the peaks of the Andes mountains and occurs from the coastal plains of Peru to moderate altitude on the western slopes of the mountains in Chile. The enormously elongate head is undoubtedly related to the need to obtain nectar from Boraginaceae with deep nectaries. Similarly elongate heads are known in a few species of Xeromelissa where additional mouthpart elongation arises primarily through lengthening of the maxillary palpus. In contrast, the maxillary palpi of Geodiscelis (Nazcoediscelis) are unmodified, as is the case in all xeromelissine genera except Xeromelissa (although they are elongate in some species of Chilicola (Hylaeosoma )) ; Geodiscelis (Nazcoediscelis) have the cardines, stipites and prementum all extremely elongate.

While three subgenera may seem excessive for a genus containing only 5 species at present, the enormous diversity found within these few species would seem to justify recognizing them at this rank. It is perhaps worth noting that there are 170 monotypic subgenera, and almost 100 monotypic genera, among the bees ( Ascher & Pickering, 2013).

All Geodiscelis species have been found associated with flowers of Heliotropium or Tiquilia , both members of the Boraginaceae . There are numerous species in this group of plants in the region encompassed by known records of Geodiscelis and additional searching among their flowers will undoubtedly result in the discovery of more undescribed bees.

Following more exhaustive searches for these interesting little bees and the discovery of more species, a formal biogeographic analysis might be of interest. Currently, the two short headed subgenera are from Argentina whereas species of the long headed subgenus are from west of the Andes.