Chilicola (Oroediscelis) calchaqui Packer and Dumesh, 2019

Packer, Laurence & Dumesh, Sheila, 2019, Fifteen new species of Chilicola (Oroediscelis) (Hymenoptera: Colletidae: Xeromelissinae) with illustrated keys to the males and females of the subgenus, Zootaxa 4559 (1), pp. 1-56 : 25-26

Chilicola (Oroediscelis) calchaqui Packer and Dumesh , new species

urn:lsid:zoobank.org:act:D71B6883-6A86-4529-A03A-60694BE04D61

( Figs. 68–69 , 129 , 131 )

Diagnosis. The relatively extreme length of the head is diagnostic for the female of this species, it is almost 1.5X longer than wide (99:68). Several species of the subgenus have heads that are 1.3–1.35X longer than wide, but not approaching the extreme relative length of this species. In addition to its extremely long head, C. calchaqui differs from the other longer headed species in the very straight, almost unbranched and uninterrupted striae of the metapostnotum.

Description. Female. Length 5.5 mm; forewing length 4.4mm, head width 1.38 mm.

Head: almost 1.5 X as long as wide, 99:68; entirely black. Clypeus imbricate, punctures irregular in size and spacing, i=1–3 d; with weak longitudinal depression for basal 2/3; supraclypeal area punctures close in size to the smaller ones of clypeus; lower paraocular area punctures i=1–2 d; frontal area densely punctate, i=0.5–1d; facial fovea weakly imbricate, no less densely punctate than adjacent frontal area; vertexal area behind compound eye with punctures in longitudinal depressions; vertexal area behind ocellar triangle sparsely punctate, i=1–5 d. Malar space longer than wide (14:11). Longest hairs on face above antennal sockets, <2 MOD; genal beard <3 MOD.

Mesosoma: pronotum with fine, dense punctures, i~d; mesoscutum somewhat dull; punctures distinct, i~d, somewhat sparser on disc, larger towards rear; mesoscutellum more weakly imbricate, punctures less regular, i=0.5–3 d; metanotum dull, punctures i=1–3 d; mesepisternum with scattered minute punctures among more abundant larger ones, i=1–3 d, sparser above and anterior to scrobe; metepisternum ruguloso-punctate above, coarsely imbricate below. Mesoscutum lacking long hairs, <0,5 MOD; mesepisternum with longest hairs <2.3 MOD. Stigma almost as long as marginal cell on costal margin (36:38); apex of stigma more gradually narrowing than in other species; distal stigmal perpendicular past middle of second submarginal cell. Metapostnotum striate, striae long, parallel, straight, rarely interrupted or branched; lateral surface of propodeum distinctly but shallowly punctate above, i=2–3 d, punctures increasingly shallow and obscure below.

Metasoma: Terga shiny, shallowly imbricate; T1 finely punctate, i=1–3 d on disc, apical impressed area mostly impunctate; T2 punctures larger and more evenly spaced around basal 1/3, i~d; finely and irregularly punctate posteriorly, i=1–8d, only apical half of impressed area impunctate, translucent; T3 more evenly punctate, i=1–2 d except more sparsely punctate towards apex, apical half of impressed area impunctate (remaining terga telescoped and not visible).

Male: unknown.

Material studied. Holotype female: ARGENTINA, Tucumán, Tafi , 2400m, ii.1986, M. Fritz [ AMNH] [See Figs. 184–185 for distribution map].

Etymology. The species is named after the indigenous Calchaqui people that used to inhabit the region of northwestern Argentina from whence this species is known.

Comments. While the male is unknown, it is expected to be readily identifiable through having a similarly elongate head. The very long head of this species is a convergent feature that has evolved independently at least five times elsewhere in the Xeromelissinae ( Packer, 2005; 2008).

Figures

FIGURES 68–69. Chilicola calchaqui. 68. female lateral habitus (holotype); 69. female face (holotype).

FIGURES 129–130. Head, frontal view, to show relative length: width. 129. L~1.5XW (C. calchaqui holotype); 130. L<1.35W (C. carPenteri paratype).

FIGURES 131–132. Heads, side view to show relative length:width of malar space. 131. L clearly> W (C. calchaqui holotype); 132. L<W (C. carPenteri paratype).

FIGURES 184–185. Distribution maps of newly described Chilicola (Oroediscelis) species. 184. Large scale map of South America showing distribution of new species; 185. Small scale map of northern Argentina to show distribution within the country.