Sclerocoelus altus, 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 : 25-26

Sclerocoelus altus sp. nov.

urn:lsid:zoobank.org:act:DF06754A-756B-4FE5-84D7-068C009579FD

Figs 5C , 16–17

Etymology

This name was chosen because S. altus sp. nov. has only been found at high elevations, between 3000 and 3800 m (from the Latin ‘ altus ’, meaning ‘high, tall’).

Material examined

Holotype

ECUADOR • ♂; Pichincha, 10 km NW of Quito, valley near Hosteria San Jorge ; 3000 m a.s.l.; 25 Oct. 1999; S.A. Marshall leg.; trailside litter; QCAZ debu00115708.

Paratypes

ECUADOR – Pichincha • 1 ♂; Campamento Pichan, near Napo; 24 Oct. 1999; S.A. Marshall leg.; sweep; debu00115967/ MYCRO897-21 sequenced for CO1-5’; QCAZ • 1 ♂; Cotopaxi National Park, Lago Limpiopungo; 3800 m a.s.l.; 25 Oct. 1999; R. Anderson leg.; paramo, shrub litter; DEBU • 1 ♂; Cotopaxi National Park, Quebrada Mishahuaycu; 3600 m a.s.l.; 25 Oct. 1999; S.A. Marshall leg.; under streamside vegetation; QCAZ • 1 ♂; same data as for preceding; near stream, pan traps; DEBU .

Description

BODY ( Fig. 16A ). Length 2.8–3.9 mm. Head dark brown, lower quarter of frons and antenna orange; face and gena orange-brown. Frontal width 2.0–2.1× frontal height. Three pairs of large interfrontal bristles surmounting a fine fourth pair; anterior orbital 0.6–0.7× length of posterior; several setulae present at bases of interfrontal and orbital setae. Palpus orange. Eye large, greatest height about 4.0× shortest genal height. Thorax dark brown, scutum with slightly paler lateral edges. Two pairs of dorsocentral bristles (anterior pair distinct, 0.5× length of posterior pair) separated by 6–7 rows of acrostichal setulae. Membrane around prosternum bare. Legs brown, hind leg darker. Fore femur with four large ventral preapical setae. Dorsal surface of mid tibia with a small offset pair of setae at about ⅓, a large anterior seta just above ½ and a large pair of setae at about ¾. Ventral surface of male mid tibia with two rows of stout setae along apical half. Wing ( Fig. 5C ) slightly infuscate. CS2 0.7–0.8 × CS3. Costa extending slightly beyond end of R 4+5 (2–3 × costal width). Halter brown.

MALE ABDOMEN ( Figs 16B–C , 17 ). Dark brown, posterior edges of tergites sometimes slightly desclerotized. T2–5 and S2–4 uniformly long-setose with large posterolateral setae. S5 broad, asymmetrical, medially 0.8 × length of S4, left side reduced, long-setose on posterior half, posteromedially acute. Anterior flange of S6+7 not developed. Sclerite A indistinct from S6+7; sclerite B dark, arched into genital pouch; sclerite C small, triangular; sclerite D dark, apically emarginate, right side fused with sclerite E; sclerite E dark, elongate, apically rounded and curved dextrally; sclerites F and G fused, large, bulging; ring sclerite indistinct. Epandrium small, 0.6 × length of S8, height 1.9 × maximum length and 0.9 × maximum width, uniformly setose; perianal pads weakly developed. Pseudocercus absent; halves of subepandrial sclerite short, arched, medially fused by a weakly sclerotized bridge. Subcercus fused medially but separate from epandrium, slightly angled anteriorly, sinuate, posterior surface with 3 setae, apex expanded posteriorly. Hypandrium moderate, anteromedial apodeme long but thin. Surstylus large, subtriangular with a triangular, inner, anterobasal lobe, outer surface convex and setose, inner surface concave. Postgonite slightly sinuate with a slight constriction about midlength and apex strongly tapered. Phallapodeme elongate, curved; basiphallus elongate and connected to distiphallus by a neck-like distal part; distiphallus largely membranous with a short dorsal sclerite and a pair of sinuate lateral sclerites, anterodorsal surface finely striate.

FEMALE ABDOMEN. Female unknown.

Remarks

Sclerocoelus altus sp. nov. is superficially very similar to S. riparius sp. nov., but differs by the unicolourous gena, distinct posteromedial projection of the male S5 lacking thickened setae, and bisinuate postgonite. Sclerocoelus altus is one of several related species, including the closely related S. punensis sp. nov. and S. puyensis sp. nov., associated with the particular microenvironment created when low branches of high Andean shrubs or herbaceous plants lie on the ground. All type specimens were taken above 3000 m a.s.l.

Figures

Fig. 5. Sclerocoelus Marshall, 1995, left wings, ventral view. A. Sclerocoelus aduncus sp. nov. B. Sclerocoelus alpinus sp. nov. C. Sclerocoelus altus sp. nov. D. Sclerocoelus argentinensis sp. nov. E. Sclerocoelus azulensis sp. nov. F. Sclerocoelus binus sp. nov. G. Sclerocoelus bucki sp. nov. H. Sclerocoelus caligarius sp. nov. I. Sclerocoelus chilensis sp. nov. J. Sclerocoelus copiosus sp. nov. Scale bars: A–J= 0.5 mm.

Fig. 16. Sclerocoelus altus sp. nov. A. Male paratype habitus, lateral view (debu00115967). B. Male paratype terminalia, posterior view (debu00108896). C. Male paratype terminalia, lateral view (debu00108896). Abbreviations: epa=epandrium; sc =subcercus; se =subepandrial sclerite; ss= surstylus. Scale bars: A= 1.0 mm; B–C =0.25 mm.

Fig. 17. Sclerocoelus altus sp. nov., paratype (debu00108896). A. Aedeagus and associated structures, lateral view. B. Male S5 and genital pouch, ventral view.Abbreviations:bp = basiphallus; dp =distiphallus; pg =postgonite; ph =phallapodeme. Scale bars: A–B =0.25 mm.