Chilicola tricarinata Packer

Packer, Laurence & Genaro, Julio A., 2007, Fifteen new species of Chilicola (Hymenoptera: Apoidea; Colletidae), Zootaxa 1468, pp. 1-55 : 29-33

Chilicola tricarinata Packer , n. sp.

( Figs. 10A–O )

Diagnosis: This species keys out to Oediscelis in Michener (2000) being more narrowly related to the group lacking a process on the first metasomal sternum in the male, this group previously having been placed in a separate subgenus, Oediscelisca , by Moure (1946), a subgenus that should be resurrected (Packer, in press).

Within the described species of this group, Chilicola tricarinata is most similar to C. dalmeidai Moure , from which it differs primarily in the narrower hind tibia in the male ( Fig. 10D ). In comparison to the large number of other new species in the “ Oediscelisca ” group available to us, the form of the hind tibia of the male is diagnostic for this species except for an additional species from southern Argentina that is described below. This latter species has the hind leg almost entirely blackish-brown, with only a small yellow spot on the outer surface of the hind femur and the extreme apex and ventral margin of the tibia yellow and the punctures on the frons are not crowded and sharp-edged as they are in C. tricarinata but separated by approximately their own diameter, the interspaces being quite shiny in contrast to the entirely dull frons in C. tricarinata . It is often not possible to differentiate females in this group (L. Packer, unpublished data).

Description. Male: Body length 5.0mm, forewing length 3.3mm, head width 1.05mm.

Colouration: Black with following parts yellow: labrum, mandible (except apex red), clypeus, apical half of anterior surface of scape (orange basally), spot on pronotal lobe and ventral-most portion of apical swelling of hind tibia. Following parts orange-tan: anterior surface of pedicel and flagellum, anterior surface of fore and mid femora and tibiae, stripe on anterior surface of hind femur, broad at base and extending almost to apex; most of ventral surface of hind tibia. All tarsi dark brown. Tegula pale amber with large yellow anterior spot. Wing veins dark brown. Apical impressed areas of metasomal terga pale amber. Metasomal sterna brown, S4–S6 suffused with pale brown.

Surface sculpture: Microsculpture moderately dense giving dull appearance except on face below antenna, genal area, legs and apical halves of metasomal terga. Labrum shiny with irregular punctation, i=1– 4d. Clypeus particularly shiny. Punctation on clypeus, supraclypeal area and lower paraocular area irregular, i=1–3d. Frons with punctures crowded, edges sharp. Vertex rugulose. Gena with weak striae and shallow obscure punctures. Pronotum and mesoscutum densely punctate, i<d; scutellum less regularly punctate i<d. Dorsal surface of propodeum rugoso-reticulate, lateral surface with only strong microsculpture below, dorsolateral area rugose. Mesopleuron densely punctate i~d. T1 densely punctate, i~d; basal depressed areas of T2– T5 strongly transversely microstriate very dull, with punctures i~2d; anterior portions of disks of terga densely punctate, i<d, punctures becoming more widely and irregularly spaced posteriorly, i=1–3d; apical impressed areas impunctate and smooth.

Pubescence: Whitish, somewhat yellowed on mesoscutum. Hairs woolly except for longer erect ones on frons and dorsal surface of thorax, those around antennae and on lower paraocular areas recumbent, partially obscuring surface ~0.5MOD. Hairs of genal beard 2MOD posteriorly gradually shorter anteriorly to 0.5MOD. Erect hairs on frons and lateral portions of scutellum and metanotum long <2MOD. T1–T3 with apicolateral hair patches, becoming sparser and less well defined from T1 to T3. S2 with moderately long erect dense pubescence slightly longer laterally, 1.2MOD, than medially, 1MOD; S3 with shorter erect pubescence slightly longer anteriorly than posteriorly, 0.5MOD decreasing to 0.3MOD; few short erect hairs on S4 and S5.

Structure: Head: ( Figs. 10A and B ) As broad as long (73:73). Labrum almost 3X as broad as long, apical margin weakly convex. Mandible more than 2X as long as basal depth (38:16). Clypeus broader than long (45:40), extending for one quarter of its length below lower ocular tangent, lacking median longitudinal groove; anterior tentorial pit punctiform. Supraclypeal area well defined above, 1.5X as long as apical width. Face lacking swellings, depressions and foveae. Eyes emarginate, strongly convergent below UOD:LOD (47:26) ( Fig. 10A ). IOC less than 2X OOC, (21:36); lateral ocellus separated from compound eye by more than its diameter. Upper ocular tangent traverses median ocellus below middle. Scape almost 3X as long as pedicel (17:6) ( Fig. 10A ), only 2X as long as greatest depth; pedicel almost spherical; F2 longer than F1 (22:18) and longer than wide (22:14) ( Fig. 10A ); F8 longer than broad (13:9); F10 and F11 subequal in length, flagellomeres lacking unusual patterns of setation or structural modifications. Vertex strongly depressed before carinate margin with occipital region. Malar space linear such that presence or absence of malar suture indetectable. Gena much shorter than width of compound eye (11:28) ( Fig. 10B ).

Mesosoma: Less than 2X as long as greatest depth, 105:56. Pronotum short, length of collar medially 0.1X as long as anterior width of pronotum (5:47) and 0.8X as long as LOL. Episternal groove complete. Dorsal area of propodeum as long as scutellum and almost 2X as long as metanotum, length of scutellum:metanotum:propodeum 18:10:18; propodeal sulcus formed of somewhat transverse pits. Hind leg as in Figs. 10D–F , trochanter with postero-medial process broadly oval in lateral view, narrowly triangular from ventral perspective; femur considerably expanded, less than 2X as long as greatest depth (52:27), ventral surface somewhat concave ( Fig. 10D ); ventral margin of tibia abruptly expanded for apical one quarter length, slightly less deep than 0.33X length (30:92), basal angulation on ventral surface strong with elongate carina narrowly separated apically from very strong carina on inner ventral margin, elongate carina on outer surface of ventral margin for middle third of tibia ( Figs. 10D–F ); hind tibial spurs unmodified; hind basitarsus 6X as long as greatest depth subparallel; hind tarsal claws bifid. Basal vein comparatively strongly but evenly curved; distal stigmal perpendicular crosses second submarginal cell at middle, stigma 0.8X as long as marginal cell on wing margin, stigmal margin on marginal cell convex apically; first recurrent and first submarginal cross veins interstitial on Rs+M.

Metasoma: Subpetiolate, T1 longer than wide (53:39). Sterna unmodified; sternal gradulus on S2 with long posteriorly directed lateral portion, that on S3 broadly interrupted medially, reduced to tiny lateral marks on S4–S5, absent on S6.

Terminalia : S7 with one pair of lateral lobes, ventral lobe large membranous and kidney shaped bearing numerous short setae; dorsal lobe reduced to minute laterally directed acute process ( Fig. 10G ). S8 with apical process very large, membranous, broadest subapically, apex angularly excised ( Fig. 10H ). Gonobase with ventral process broad and emarginate medially. Volsella narrow, outer surface broadly concave, apex of digitus forming angle of approximately 60º. Gonostylus not demarcated from gonocoxite, broad, apex rounded and directed somewhat mesad. Penis valve narrow with one very small membranous lobe ( Figs. 10I and J ).

Female: Body length 4.5mm, wing length 3.2mm, head width 1.0mm.

Colouration: Body entirely blackish-brown except as follows: Labrum and anterior surface of F2–F10 brown. Tegula dusky translucent. Much of mandible, basal two thirds of anterior surface of fore tibia and large basal spot on midtibia orange. Basal spot on mandible yellow.

Surface Sculpture: Microsculpture weaker than in male except on clypeus; punctures smaller and sparser than in male, on clypeus and lower paraocular area i~2d, on supraclypeal area i~3d, on frons i<d, vertex with weak transverse microstriations and weak punctures; dorsal surface of thorax with i~d, mesopleuron with i=1–2d, metasomal terga with anterior portions weakly transversely microreticulate, disks of terga with minute punctures, i=1–2d, sparser on more posterior terga.

Pubescence: Shorter and less woolly than in male, recumbent hairs on face restricted to area laterad and immediately beneath antennal sockets, not obscuring surface. Hind leg with weak scopa, hairs ~1.5MOD on trochanter, femur and tibia. Scopa of S2 corbiculate, hairs long 3MOD, with anteriorly directed branches decreasing in length towards apex.

Stucture: As in male except for usual secondary sexual differences and as follows: Mouthparts not dissected in sole specimen, premental fovea almost completely covering ventral surface, margins strongly carinate. Compound eyes less convergent below, UOD:LOD 42:29 ( Fig. 10C ). Vertex flat in profile. Facial fovea present at emargination of compound eye shallow, 2X as long as greatest breadth (12:6) ( Fig. 10C ). Propodeal sulcus narrower and shallower than in male. Apical lunule of S5 more than 2X as long as apical breadth.

Sting apparatus: Hemitergite 7 ( Fig. 10K ) elongate more than 2X as long as greatest breadth excepting lateral lamella, apodemal region elongate and narrow, medial portion of marginal ridge somewhat concave, spiracle slightly closer to lateral than medial margin, lateral process short with anteriorly and posteriorly directed apical angulations, anterior one longer, lateral lamella 0.7X as long as greatest breadth of hemitergite, posterior margin of lamina spiracularis straight. Hemitergite 8 with apodeme broad, anterior ridge straight ( Fig. 10L ). First valvifer with dorsal surface almost straight, ventral surface slightly sinuate, ventral process slightly longer than dorsal one. Second valvifer with apodemal ridge somewhat sinuate; apical process acute; spinous process very long, more than 2X basal width; gonostyli gradually narrowed posteriorly. Sting shaft very slightly concave ventrally ( Fig. 10M ). Furcula with ventral arms moderately broad, parallel-sided; dorsal and ventral arms subequal in length; very narrow in lateral view ( Figs. 10N and O ).

Material Studied. Holotype male, allotype female and five paratype males (one in glycerin) ARGEN- TINA: Catamarca: 25km N. of Andalgala, 14.ii.03 L. Packer; additional material: Catamarca: 20km N. of Andalgala, 27°29'477" S 066°23' 006"W, 1736m, 14.ii.03 L. Packer, four paratype males. All specimens are at PYU except for male holotype, female allotype and one paratype male at MACN and one male paratype in each of: IML and CTMI.

Etymology. The specific epithet refers to the ventral surface of the hind tibia, which bears three strong carinae.

Comments. This species, the following one ( C. tricarinatoides ) and numerous undescribed species appear to form a monophyletic group with C. friesei Ducke and C. dalmeidai Moure , which were originally placed in a new subgenus, Oediscelisca , by Moure (1946), but subsequently sunk by Michener (1995) within Chilicola (Oediscelis) . Although this group of species shares male hind leg modifications with C. (Oediscelis), other features, such as the punctiform anterior tentorial pit, and details of the male genitalia, indicate that C. ( Oediscelisca ) group may be quite distantly related to C. (Oediscelis). Moure’s subgeneric name for these bees should be reinstated (Packer, unpublished data).

Figures

FIGURES 10 A – O. Chilicola tricarinata Packer, n. sp. Head of male: A. frontal view, B. lateral view. C. frontal view of female head. Male: D. hind leg outer view. E. hind tibia ventral view, F. hind tibia inner view. G – J. Male terminalia. G. S 7. H. S 8. I. genital capsule, J. same lateral view. Dorsal views are at the left. K – O. Sting apparatus of female: K. hemitergite 7, L. hemitergite 8, M. First and second valvifer with gonostylus and sting shaft, N and O, furcula in ventral and lateral views respectively. Stippling in A, B and D – F indicates pale colouration, elsewhere it indicates membranous regions.