Chlerogella octogesima (Brooks & Engel) Engel, 2010

Engel, Michael, 2010, Revision of the Bee Genus Chlerogella (Hymenoptera, Halictidae), Part II: South American Species and Generic Diagnosis, ZooKeys 47 (47), pp. 1-100 : 57-58

Chlerogella octogesima (Brooks & Engel) , comb. n.

Map 3

Ischnomelissa octogesima Brooks and Engel, 1998: 187 . Moure et al., 2007: 800; Engel and Brooks, 2002: 5.

Holotype. ♁, ECUADOR: Napo, Misahualli, 1 hr. down Río Napo, 19 November 1983, L. Huggert ( PMAE).

Diagnosis. Refer to diagnosis for C. silvula (vide supra).

Description. Modified after Brooks and Engel (1998): Male: Total body length 6.67 mm; forewing length 4.58 mm. Head length 1.73 mm, width 1.19 mm. Distal three-quarters of clypeus extending below lower tangent of compound eyes. Malar space about as long as basal mandibular width. Upper interorbital distance 0.58 mm; lower interorbital distance 0.37 mm. First flagellomere about as long as pedicel, about as long as wide and about one-half length of second flagellomere; ventral surfaces of second through eleventh flagellomeres densely covered in placoid sensilla, placoid fields not disrupted. Upper portion of pronotum medially depressed, not elongate, medially less than 0.25 times ocellar diameter in length; ventral portion of preëpisternal sulcus not broad, similar to scrobal sulcus and upper portion of preëpisternal sulcus; mesoscutellum weakly convex, not bigibbous. Basal vein distad cu-a by three times vein width; 1rs-m distad 1m-cu by three times vein width; 2rs-m distad 2m-cu by six times vein width, 2rs-m relatively straight; first submarginal cell longer than combined lengths of second and third submarginal cells; second submarginal cell slightly narrowed anteriorly, anterior border of second submarginal cell along Rs shoter than that of third submarginal cell; posterior border of third submarginal cell about 2.5 times as long as anterior border. Distal hamuli arranged 2-1-2. Inner metatibial spur serrate. Ventral fringe of setae on ventral gonostylar process decreasing in length to very short apically and distinctly thickened and curved, almost hooked, at their apices; penis valves lacking elongate setae dorsoapically.

Clypeus and supraclypeal area faintly imbricate with weak punctures separated by 0.5–1.5 times a puncture width; face with small, contiguous punctures, more widely spaced in malar space; punctures of face blending to smooth integument in ocellocular area and vertex, with punctures separated by 1–2.5 times a puncture width; gena smooth with small punctures separated by 1–3 times a puncture width; postgena imbricate and impunctate. Pronotum smooth with scattered minute punctures; mesoscutum faintly imbricate with minute punctures separated by 1–3.0 times a puncture width; mesoscutellum as on mesoscutum. Preëpisternum smooth with faint contiguous punctures; mesepisternum finely imbricate with minute punctures separated by 1–3 times a puncture width; metepisternum smooth. Propodeum strongly imbricate. Metasoma weakly imbricate.

Mandible pale with black apex; labrum, clypeal apex, and apical half of malar space pale; antenna brown; remainder of head and mesosoma metallic green, except tegula brown amber and semi-translucent. Legs amber except outer surface of metafemur slightly darker. Metasomal TI–III with apical half brown, basal half amber; TIV–VII entirely brown.

Pubescence pale white; setae of mesoscutellum of moderate length. Terga with scattered simple setae progressively becoming longer and more numerous on apical terga; SI and SII with scattered simple setae; SIII with strong apical fringe of setae and SIV with less strong but very distinct brush of setae; SV and SVI with a less dense preapical band of setae.

Female: Unknown.

Comments. The female for C. octogesima remains unknown and, given the similarities of the males of C. octogesima and C. silvula , may prove difficult to distinguish if not captured alongside males. The species was originally placed in Ischnomelissa based on an incomplete knowledge of variation in Chlerogella . Given that the species had a short head and that the female was unknown (the most significant character at that time being the inner metatibial spur of females), the species was attributed to Ischnomelissa as no Chlerogella were known to have short malar spaces and despite the more elaborate and contorted gonostylar process which itself was not known among the otherwise relatively simple species of Ischnomelissa (but again, the genitalia of Chlerogella males was almost entirely unknown in 1998 as even the growing number of new, undescribed species at that date were known principally from females). It is now understood that malar length alone cannot exclude this species from Chlerogella and, more importantly, the structure of the gonostylar process is distinctive to Chlerogella (refer to the generic account, vide supra). Accordingly, this species is herein transferred to Chlerogella .