Sclerocoelus punensis, Kuwahara & Marshall & Paiero, 2025

Kuwahara, Gregory K., Marshall, Stephen A. & Paiero, Steven M., 2025, A revision of the genus Sclerocoelus Marshall (Diptera: Sphaeroceridae), European Journal of Taxonomy 979, pp. 1-277 : 93-94

Sclerocoelus punensis sp. nov.

urn:lsid:zoobank.org:act:076ADC38-4F25-4744-B9C7-5AD35CC10F33

Figs 8H, 114–115

Etymology

The species name reflects the high elevation habitat of this species.

Material examined

Holotype

BOLIVIA • ♂; La Paz , Lake Titicaca, W of Guaqui; 16°35′56″ S, 68°53′52″ W; 3810 m a.s.l.; 19 Apr. 2001; S.A. Marshall leg.; stream, sweep; CBFC.

Paratypes

PERU – Cusco • 7 ♂♂; Cusco, Quebradas Salineras ; 3550 m a.s.l.; 3 Aug. 1971; C. and M. Vardy, leg.; BMNH . – Junín • 1 ♂; Ondores ; 4100 m a.s.l.; 28–31 Dec. 1980; Gärdenfors, Hall and Samuelsson leg.; puna and wet pastures; MZLU .

Description

BODY ( Fig. 114A). Length 2.4–3.0 mm. Head dark brown, lower third of frons orange; face and gena orange-brown, antennae brown. Frontal width 2.3–2.4 × frontal height. Three pairs of strong interfrontal bristles surmounting a fine fourth pair; anterior orbital 0.4–0.5 × length of posterior. Palpus yellow. Eye slightly reduced, greatest height about 2.5 × shortest genal height. Thorax dark brown, scutum with paler lateral edges. Two pairs of dorsocentral bristles (anterior pair distinct, 0.7× length of posterior pair) separated by 7–8 rows of acrostichal setulae. Membrane around prosternum bare. Legs brown, mid and hind femora darker. Fore femur with four large ventral preapical setae. Ventral surface of male mid tibia with two rows of stout setae in apical third. Wing ( Fig. 8H) hyaline. CS2 0.7–0.8 × CS3. Halter brown.

MALE ABDOMEN ( Figs 114B–C, 115). Dark brown, posterior edges of tergites sometimes slightly desclerotized. T2–5 and S2–4 uniformly long-setose with large posterolateral setae. S5 rectangular, 1.3× length of S4, posterolaterally long-setose, medially depressed and strongly darkened, lateral quarters darkened and anterior edge dark. Anterior flange of S6+7 not developed. Sclerites A not well differentiated from S6+7; sclerites, B, C, and D absent(?); sclerite E large, dark, tapered, and curved posteriorly; sclerite F large, dark and tapered; sclerite G small, not well developed; ring sclerite very large and very well sclerotized with a prominent mesial lobe. Epandrium very large, 0.9 × length of S8, height 1.9× maximum length and 1.0 × maximum width, uniformly setose with very long setae in anterolateral corners; perianal pads weakly developed. Pseudocercus inconspicuous, fused to epandrium; halves of subepandrial sclerite simple, slightly sinuate, and narrowly fused medially. Subcercus very large, triangular and apically curved posteriorly. Hypandrium with sinuate anteromedial apodeme. Surstylus with a broad anterolateral ridge bearing a row of long setae and an elongate, setose posteroventral lobe which has a prominent, bare, ventral process. Postgonite long, curved anteriorly, with a stout anterior lobe at about basal third and apex bent ventrally. Phallapodeme very large with sclerotized dorsal and ventral ‘fins’; basiphallus wedge-shaped with a curved, beak-like epiphallus; distiphallus basally sclerotized with two large, apical membranous lobes.

FEMALE ABDOMEN. Female unknown.

Distribution

Neotropical: Bolivia, Peru.

Remarks

Sclerocoelus punensis sp. nov. is superficially similar to S. puyensis sp. nov. but can be distinguished by the medially depressed male S5, apically bifurcate surstylus, apically tapered subcercus, and sinuate postgonite. Sclerocoelus punensis , like other ‘basal’ Sclerocoelus lineages, is a high Andean species. All known specimens were collected above 3500 m a.s.l. The holotype is from Lake Titicaca (about 3800 m a.s.l.), where it was taken in the same samples as S. lutosus sp. nov. and close to where S. mandibulum sp. nov. was collected.