Chilicola (Stenoediscelis) denisii Packer

Packer, Laurence & Genaro, Julio A., 2007, Fifteen new species of Chilicola (Hymenoptera: Apoidea; Colletidae), Zootaxa 1468, pp. 1-55 : 37-41

Chilicola (Stenoediscelis) denisii Packer , n. sp.

( Figs. 13A–H )

Diagnosis: On the basis of numerous characteristics this species is clearly a member of Toro and Moldenke’s subgenus Stenoediscelis, subsumed within Anoediscelis by Michener (1995), but deserving of subgeneric status based upon phylogenetic analysis (Packer, in press). Synapomorphies for Stenoediscelis include, for both sexes, the previously unnoticed notched parascutal carina ( Fig. 13D ); in the male, the form of the hind tibia and basitarsus, both of which are slightly outwardly concave ( Fig. 13E ), and the terminalia with a particularly characteristic S7 ( Fig. 13F ); and in the female the subapical mandibular tooth, which is as long as, or almost as long as, the apical tooth and the presence of a medial angulation basal to the subapical tooth (Packer, in press).

Males of Chilicola denisii can be differentiated from the two described species of Stenoediscelis, C. inermis (Friese) and C. mailen Toro and Moldenke , on the basis of its almost entirely dark hind tibia. Two additional undescribed species are known from the same geographic region as the type locality for C. denisii in Patagonian Argentina. One can be differentiated from C. denisii on the basis of size; it is less than 3.5mm in length whereas C. denisii is 4.5–5.0mm, as well as having narrow pale rings on the base and apex of the hind tibia. The remaining species is as large as C. denisii and like it has an entirely dark hind tibia, but has the ventral surface of the hind femur angulate at the base so that it attains its maximum depth in its basal quarter. The hind femur of C. denisii is not swollen basally and attains its maximum depth near midlength ( Fig. 13E ).

Females of the new species can be differentiated from C. inermis and C. mailen by their generally sparse and irregular mesoscutal punctation, with i=1–5d as opposed to i=1–2d. The smaller of the undescribed species noted above also has irregular and sparser punctation but can be differentiated readily on the basis of size as noted.

Description. Male: body length 5.0mm, forewing length 3.0mm, head width 0.9mm.

Colouration: Black, with following parts yellow: Labrum, mandible (except apex red-brown), all of clypeus, lower paraocular area extending to half distance between anterior tentorial pit and upper margin of clypeus. Following parts orange or yellow-orange: Pedicel and flagellum, apical spot on fore- and midfemur, anterodorsal surface of foretibia, foretarsus, basal and apical rings on midtibia. Following parts testaceous: Mid- and hindtarsi and apical ring on hindfemur. Posterior surface of flagellum brown. Tegula translucent dusky brown. Wing veins dark brown, tending to testaceous towards base. Apical impressed areas of metasomal terga translucent dusky brown.

Surface Sculpture: Labrum coarsely and irregularly punctate (i<d) on moderately shiny background. Clypeus shiny apically, with weak microsculpture elsewhere, with irregular weak punctures, i=2–5d. Yellow portion of lower paraocular area with few punctures, dark portion and upper paraocular area with distinct dense punctures i~d. Frons with punctures i=1–3d. Vertex weakly rugulose. Genal area with small punctures, i=1–2d. Pronotum with shallow dense punctures, i<d. Mesoscutum, scutellum and metanotum shiny despite dense microsculpture. Mesoscutum with punctures irregular i=1–4d, denser along anterior and posterior margins; scutellum with denser, more distinct punctures; metanotum with shallow irregular punctures. Mesepisternum shiny, above scrobe with few minute punctures, rest of mesopleuron weakly and irregularly punctate, i<2–4d. Disk of dorsal surface of propodeum rugulose, remainder and lateral surface impunctate, dorsolateral area weakly roughened. T1 with obscure shallow punctures, i>d, becoming sparser on more posterior terga, apical impressed areas impunctate with weaker microsculpture.

Pubescence: White, short and sparse, not especially plumose; longest on genal area (2MOD), of intermediate length on legs and ventral surface of mesosoma . Without apico-lateral hair patches on metasomal terga and no specialized hair patches on metasomal sterna.

Structure: Head: Longer than broad, length to width 13:12 ( Fig. 13A ). Labrum 2X as broad as long, apical margin slightly produced medially. Mandible length:basal depth ~2:1. Clypeus shorter than broad 38:45, lower one quarter extending beyond lower ocular tangent, lacking median longitudinal groove ( Fig. 13A ). Epistomal suture expanded below anterior tentorial pit into elongate comma, pit adjacent to suture. Subantennal sutures weakly concave outwardly. Supraclypeal area somewhat protuberant dorsally, flat below, length:breadth 25:21. Frons lacking swellings or depressions. Frontal line raised for lower 0.4X distance between supraclypeal area and median ocellus, replaced by narrow depression for remaining 0.6X. Facial fovea present but extremely weakly developed as comparatively shiny area with weak wrinkling in surface above and below. Inner margin of compound eye weakly emarginate, strongly convergent below ( Fig. 13A ), UOD:LOD 77:48. OOC:IOC 22:28. Lateral ocellus separated from compound eye by slightly less than 2X its diameter. Vertex rounded in frontal view, slightly longer than LOL in dorsal view. Upper ocular tangent approximately 0.6MOD below lower margin of median ocellus. Scape slightly shorter than pedicel+F1+F2 combined, almost 3X as long as broad; F1 slightly broader than long; F2–F10 almost 2X as long as broad; F11 0.75X as long as F10; flagellum not markedly increasing in breadth from F1 to F11; flagellomeres lacking unusual patterns of setation or structural modifications. Genal area narrower than compound eye (28:40) ( Fig. 13B ). Malar space linear such that presence or absence of malar suture indetectable.

Mesosoma: Elongate , approximately 2X as long as greatest depth. Pronotal collar short, subequal to LOL. Mesoscutum with parascutal carina notched ( Fig. 13D ). Episternal groove complete; scrobal groove weakly defined posterior to scrobe, absent anteriorly. Propodeum elongate, dorsal surface as long as posterior depth and subequal to length of scutellum (scutellum:metanotum:propodeum 30:15:23), propodeal sulcus absent, area outside of dorsal triangle of propodeum swollen, and dorsal and posterior surfaces at angle of 135º to each other. Hind trochanter unmodified. Hind femur 2.5X as long as greatest depth, convex ventrally. Hind tibia laterally compressed, narrow basally, gradually expanding to apical third, somewhat parallel sided to apex, length to greatest depth 90:23, attaining base of trochanter when folded, lacking angles or carinae ( Fig. 13E ). Hind tibial spurs somewhat short but not robust, strongly curved or sclerotised. Hind basitarsus very slightly concave outwardly and slightly downcurved, 5.5X as long as greatest depth ( Fig. 13E ). Hind tarsal claws bifid. Basal vein weakly curved near base; distal stigmal perpendicular crossing near middle of second submarginal cell; stigma shorter than length of marginal cell on wing margin; stigmal margin on marginal cell angularly convex; first recurrent vein apical to first submarginal cross vein.

Metasoma: Length and apical width of T1 subequal; T2 and T3 with weak basal depressions; apical impressed area approximately 0.25X length of tergum. Metasomal sterna unmodified except S1 concave subapically in profile.

Terminalia : S7 with ventral lobe L-shaped and posteriorly directed, bearing row of long hairs in basal half of outer surface and a few short hairs at extreme apex, dorsal lobe short and flat ( Fig. 13F ). S8 with apical lobe narrowly joined to rest of sternum, apex concave. Gonobase with lateral projection of ventroapical process broadly rounded ( Fig. 13G ). Volsella with outer margin angularly and deeply concave before apex. Gonoforceps elongate, gonostylus poorly demarcated from gonocoxite, elongate and narrow. Penis valve with two long membranous lobes, medial one dorsally oriented, lateral one bent inwardly at right angles over medial lobe ( Fig. 13H ).

Female: Body length 4.5mm, wing length 2.6mm, head width 1.0mm.

Colouration: Entirely dark brown-black except anterior surface of F4–F10 pale orange and apical impressed areas of metasomal terga amber.

Surface Sculpture: As in male except as follows: Labrum with large dense punctures, i<d. Clypeus with punctures more distinct, i=1–4d. Lower paraocular area regularly punctate, i=d; upper paraocular area with shiny almost impunctate area. Frons more regularly punctate, i=2d. Vertex with weak transverse wrinkles. Genal area with distinct punctures anteriorly, i~d. Hypostomal area shiny lacking microsculpture with few minute punctures. Mesoscutum with punctures irregular, i=1–5d. Metanotum with punctures more distinct and regular than in male, i~d;

Pubescence: Longest hairs on frons <1.5MOD; on genal area, <2MOD; on lateral surface of thorax 1MOD. Hind trochanter, femur and tibia with sparse scopal hairs <2MOD. Metasomal terga lacking apicolateral hair patches. S2 with long scopal hairs forming corbicula, <4MOD, with widely spaced, short branches on anterior surface.

Structure: As in male except for usual secondary sexual characteristics and as follows (mouthparts and sting apparatus not dissected in sole female specimen): Head longer, length to width 13:11 ( Fig. 13C ). Labrum 2.5X as wide as long, with circular apicomedial ridge, bearing tuft of setae. Mandible with subapical tooth as long as apical one and with mesal angulation basal to subapical tooth. Frons lacking swellings or depressions. Frontal line raised for lower 0.6X distance between supraclypeal area and median ocellus. Facial fovea absent but represented by shiny almost impunctate area. OOC:IOC 24:26. Upper ocular tangent approximately 1MOD below lower margin of median ocellus. Gena shorter than width of compound eye (30:36). T1 broader, length to width 60:85. S5 with apical lunule 0.75X as long as apical width.

Material studied. Holotype male: ARGENTINA, Santa Cruz, 20km E. of Los Antiguos, 46 o36’595” S 0 71 o21’472”W 17.xi.2003, pan trap, L. Packer; allotype female: same except 0.5km E. of Los Antiguos, 46°33’500” S 071°35’ 507”W, 237m, 17–19.xi.2003, pan trap, L. Packer. Both known specimens will be housed at MACN. The holotype bears a blue label that states: VOUCHER SPECIMEN DNA EXTRACTION E.A.B. Almeida #58 extraction date: 7/2004.

Etymology. This species is named, with gratitude and affection, after the senior author’s father, who ensured that the senior author was not afraid of insects as a child.

Comments. The genitalia of this species are very similar to those of C. inermis and particularly, C. mailen , but the outer margin of the ventral lobe of S7 is straighter and the whole lobe more L-shaped, whereas in the other two species the outer margin is rounded and the whole lobe more lunate. In C. inermis the ventral lobe of S7 is also more gradually narrowed to the apex and the basal bare area longer than in the other two species.

Figures

FIGURES 13 A – H. Chilicola denisii Packer, n. sp. Head of male: A. frontal view, B. lateral view. C. frontal view of female head. Male: D. Lateral view of portion of thorax to show notch in parascutal carina (arrow), E. Hind leg outer view of femur and tibia on left, dorsal view of tibia and basitarsus on right. F – H. Male terminalia. F. S 7. G. S 8. H. genital capsule, dorsal views are at the left.