Chilicola tregualemu Packer

Packer, Laurence & Genaro, Julio A., 2007, Fifteen new species of Chilicola (Hymenoptera: Apoidea; Colletidae), Zootaxa 1468, pp. 1-55 : 43-47

Chilicola tregualemu Packer , n. sp.

( Figs.15A–O )

Diagnosis. This species appears related to a group of three other Chilean species: C. minor , C. olmue and C. orophila Toro and Moldenke , based upon the spinose male hind trochanter ( Figs. 15D and E ) (simple in C. orophila ), somewhat expanded ventral apex of the male hind tibia ( Fig. 15E ) and the general form of the male S7 ( Fig. 15G ). It can be differentiated from all three species by its larger size, entirely dark legs, more complex armature of the hind trochanter and genitalia of the male. No other Chilean species of Chilicola is as uniformly darkly coloured as this species: females of two of the aforementioned species have at least small pale spots at the extreme base of the fore- and midtibia (females are unknown for C. orophila ).

Description. Male: Length 6.5mm, forewing length 3.5mm, head width 1.3mm.

Colouration: entirely brownish-black except for narrow transverse apical dark orange mark on clypeus. Tegula brown. Wing veins dark brown, membrane amber.

Surface Sculpture: Generally dull through combination of dense punctation and microsculpture. Labrum shining with discrete punctures, i<d, except sparser medially towards base. Clypeus shining for apical 1/6th, microsculpture increasingly deep towards base, punctures irregular i=0.1–2d. Punctures slightly larger and with i<d on lower paraocular area. Supraclypeal area with finer more regular punctures, i~d. Face above antennae with small crowded sharp-edged punctures. Vertex densely and finely roughened, punctures difficult to discern. Genal area with weak moderately dense punctures against longitudinally microstriate background. Pronotum with dense small punctures, i<d. Mesoscutum with small dense punctures, crowded for anterior one third and along posterior margin, i~0.5d on disk; scutellum with i<d somewhat shiny between punctures; metanotum with small, crowded, sharp edged punctures. Mesopleuron irregularly punctate, area above scrobal groove almost impunctate, below groove i=0.5–2d. Dorsal surface of propodeum densely rugose, posterior and lateral surfaces microreticulate with sparse, shallow punctures, dorsolateral area with elongate punctures, i<d. Metasomal terga dull, with strong microsculpture and dense shallow irregular punctures, i<d.

Pubescence: Brown on face and thoracic dorsum, white elsewhere. Face with short erect brown pubescence, <1MOD, longer on vertex ~1.5MOD. Genal beard 0.5MOD anteriorly, 2MOD posteriorly. Dorsal surface of thorax with sparse long hairs 1MOD. Posterior margin of mesoscutellum, metanotum and mesopleuron and lateral surface of propodeum with denser longer hairs,>2MOD. Outer surface of hind tibia with dense patch of long apically directed hairs, more ventral ones curved dorsally 2MOD ( Fig. 15E ). Metasomal terga lacking apicolateral hair patches. Sterna glabrous.

Structure: Head: Round, length equal to breadth ( Fig. 15A ). Labrum 3X broader than long. Clypeus shorter than broad (52:60), apical 0.4 extending beyond lower ocular tangent, with weak medial depression ( Fig. 15A ). Epistomal suture expanded below anterior tentorial pit forming elongate comma, pit not separated from suture. Subantennal sutures slightly convergent below, outwardly concave. Supraclypeal area welldefined dorsally, length to breadth 20:15. Frontal line strongly carinate for lower half of distance between supraclypeal area and median ocellus. Facial fovea absent ( Fig. 15A ). Inner margin of compound eye emarginate; eyes strongly convergent below ( Fig. 15A ), UOD:LOD 52:30. IOC more than OOC (16:12). Upper ocular tangent just below lower margin of median ocellus. Vertex weakly convex in frontal view; length 1LOL; margin with occipital region sharp but not carinate. Antenna very long and thin, scape 3X as long as apical width and 3X as long as pedicel; pedicel shorter than broad; F1 1.5X as long as wide (25:18); remaining flagellomeres slightly longer (30:19) except F11 24:18; antenna lacking unusual setation or structural modifications. Malar space linear such that presence or absence of malar suture indetectable. Gena less than 0.5X as wide as eye (16:34) ( Fig. 15B ).

Mesosoma: Less than 2X as long as greatest depth, 13:7. Pronotal collar with dorsal surface moderately long, 1.5MOD medially. Episternal groove well developed; scrobal groove well developed posteriorly, absent anteriorly. Dorsal area of propodeum intermediate in length between metanotum and scutellum, ratio of scutellum:metanotum:dorsal surface of propodeum 40:18:24); propodeal sulcus barely detectable. Hind trochanter with three apicoventral angles, outer one triangular, middle one a minute tooth, inner one a mesally oriented narrow spine ( Figs. 15D and E ). Hind femur somewhat expanded, less than one third as deep as long (40:110), ventral surface gently concave ( Fig. 15E ). Hind tibia strongly expanded for basal two-thirds from narrow base, greatest depth more than one third length (23:60), apical one third produced into broad, flattened pad, apex slightly produced beyond base of unmodified tibial spurs ( Figs. 15E and F ). Hind basitarsus deepest near base, narrowing towards apex, length to greatest depth 4:1. Hind tarsal claws bifid. Basal vein weakly curved; stigma in marginal cell weakly convex, ratio of its length to marginal cell apical to stigma 60:100; distal stigmal perpendicular crossing second submarginal cell basal to middle; first recurrent vein interstitial with first submarginal crossvein.

Metasoma: T1 as long as wide; apical impressed areas 0.25X as long as tergum. Sterna lacking unusual projections, S2 with lateral portion of gradulus short, S3–S5 with small circular lateral gradular marks.

Terminalia : S7 with one pair of well developed lateral lobes; rudiment of ventral lobe a slight extension of apex of disc of sternum; dorsal lobe sclerotised and apicolaterally directed, bearing transverse row of long bristles, anterolaterally directed basally becoming laterally oriented towards apex, ( Fig. 15G ). S8 with apical process broadly rounded at sides, posterior margin concave ( Fig. 15H ). Gonobase with ventroapical process long and narrow, apically shallowly concave. Volsella with angulate lateral margin. Gonocoxite elongate, parallel-sided. Gonostylus well demarcated from gonocoxite, strongly convex on outer surface, concave on inner surface, narrowed towards base; ventromedial lobe slightly more than right angular, sinuate. Penis valve with two membranous lobes, outer one somewhat curved around inner one, inner one elongate and narrow ( Fig. 15I ).

Female: As in male except for usual secondary sexual characteristics and as follows: Length 4.8mm, wing length 3.5mm, head width 1.1mm.

Colouration: Entirely dark brown except for apex of mandible (reddish); tegula and apical impressed area of metasomal terga translucent testaceous.

Surface Sculpture: Labrum with large, irregular punctures i<d on shiny background. Clypeus and supraclypeal area with larger shallow irregular punctures i=0.1–2d. Frons with punctures dense to crowded below, sparser in front of ocelli, i~d. Vertex with weak transverse striae and shallow punctures. Genal and hypostomal areas with sparse obscure punctures. Pronotal collar with shallow punctures, i~d. Mesoscutum with small but dense punctures, i<d, almost crowded posteriorly; scutellum regularly punctate, i~d. Mesopleuron with small irregular punctures, i=2–5d, denser on upper half of hypoepimeral area, i=0.5–2d. Dorsal surface of propodeum strigate apically, rugulose basally; rest of propodeum almost impunctate shiny with weak microsculpture; dorsolateral area narrowly weakly roughened. Metasomal terga with very obscure and sparse punctures.

Pubescence: White except on frons and vertex pale fuscous and on apical metasomal terga pale brown, fine; mostly short, a few long hairs 2MOD on frons and genal area, 1.5MOD on lateral surface of mesosoma and hind tibial scopa. Dorsolateral area of propodeum with narrow area of hairs, 1MOD. Apicolateral patches of short plumose hairs on T1 and T2. Corbicula of S2 with long hairs, 3MOD, with numerous short branches anteriorly. S5 with apical lunule broadly U-shaped, 0.8X as long as broad.

Structure: Head: Longer than broad, length to width 75:68 ( Fig. 15C ). Maxillary palpus with segments increasing in length and decreasing in breadth from first to last, 0.75X as long as prementum. Prementum 0.2X as broad as long, with fovea covering most of ventral surface, margins strongly carinate. Lacinia an elongate triangle, more than 4X as long as greatest breadth. Lorum well sclerotised, approximately 0.33X as long as cardo. Labrum 2.5X as broad as long (38:15), apical margin almost straight. Mandible 2.5X as long as basal depth, subapical tooth long. Clypeus slightly longer than broad (52:50), slightly more than lower one quarter extending beyond lower ocular tangent, lacking median longitudinal groove ( Fig. 15C ). Supraclypeal area as broad as long ( Fig. 15C ). Frons above antenna very weakly depressed; frontal line distinct, but less strongly carinate, for lower half of length between supraclypeal area and median ocellus. Facial fovea absent but represented by shiny area; inner margin of compound eye emarginate ( Fig. 15C ) less strongly convergent below UOD:LOD 87:56. OOC equal to IOC. Vertex longer than length of lateral ocellus, 17:14, abruptly rounded onto occipital region.

Mesosoma: Elongate , ratio of distance from anterior of pronotal collar to articulation of metasoma to greatest depth of mesosoma 100:55. Pronotal collar short, almost entirely declivous medially. Stigma shorter than length of marginal cell on wing margin (50:68); first recurrent vein and first submarginal crossvein approximately interstitial.

Metasoma: T1 shorter than wide (80:115); apical impressed areas poorly defined, approximately 0.25X length of tergum.

Sting apparatus: Lateral portion of marginal ridge of hemitergite 7 thick, well sclerotised evenly curved from apodeme to apex; lateral process short and narrow with apical spine; spiracle somewhat closer to lateral than medial portion of marginal ridge; posterior margin of lamina spiracularis straight ( Fig. 15J ). Hemitergite 8 with apodemal ridge straight, apodeme and plate approximately equal in size, medial portion of plate sinuate ( Fig. 15K ). First valvifer with dorsal process short and narrow, ventral process elongate. Second valvifer with incisura postarticularis narrowed medially, somewhat expanded basally and apically ( Fig. 15L ). Sting shaft curved ventrad ( Fig. 15M ). Furcula with ventral arms broad, especially towards junction with dorsal arm, narrower than dorsal arm in lateral view (Figs. N and O).

Material Studied. Holotype male and allotype female. CHILE; Maule; Tregualemu , 30km W. of Cauquenes, 27.i.1979. L. E. Peña. The types belong to the AMNH.

Etymology. This species is named after the type locality.

Comments. The locality is a small coastal town in a poorly collected part of Chile where there remain a few areas of comparatively undisturbed habitat (A. Ugarte, pers. comm., 2004). This species, belongs to a group that also includes C. minor , C. olmue and C. orophila . These species were originally placed in Heteroediscelis by Toro and Moldenke (1979). This subgenus was divided among Anoediscelis and Oediscelis by Michener (1995) with the three species mentioned above moved to the former. These three, plus C. tregualemu do not fit in any named subgenus and phylogenetic analysis suggests that a new subgeneric name is required for this group (Packer, in press). Among the previously known related species, C. tregualemu has a male S7 and setation of the hind tibia very similar to that of C. olmue and the dense mesoscutal punctation of C. minor .

Figures

FIGURES 15 A – O. Chilicola tregualemu Packer, n. sp. Head of male: A. frontal view, B. lateral view. C. frontal view of female head. Male: D. Hind trochanter, ventral view. E. Hind leg trochanter, femur and tibia, outer view. F. Hind tibia, oblique ventral view. G – I. Male terminalia. G. S 7. H. S 8. I. genital capsule. Dorsal views are to the left. J – O. Sting apparatus of female: J. hemitergite 7, K. hemitergite 8, L. First and second valvifers. M. sting shaft. N and O. Furcula dorsal and lateral views respectively. Stippling in A indicates dark orange colouration, elsewhere it indicates membranous regions.