Leptocera longilimbata Buck, 2009

Buck, Matthias & Marshall, Stephen A., 2009, Revision of New World Leptocera Olivier (Diptera, Sphaeroceridae), Zootaxa 2039 (1), pp. 1-139 : 48-49

Leptocera longilimbata Buck , new species

( Figs. 76–79 )

Description. Relatively small, body length ca. 2.2 mm. Indistinguishable from L. aequilimbata except for the following characters ( Figs. 76–79 ): male sternite 5 with ca. nine long scales of subequal length ( L. aequilimbata has only 5–8 scales, and in those specimens with more numerous scales the lateral ones are always distinctly shorter than the medial ones). Anterior section of surstylus with point of anterior process more projecting (appearing longer) in lateral view (though some L. aequilimbata have the point more projecting than in Fig. 38 ); ventral lobe with long posterior bristle more removed from dorsal margin than in L. aequilimbata , second bristle from hind margin inserted dorsomedial to crest of ventral lobe (its socket thus not visible in lateral view; in L. aequilimbata this bristle is inserted on the crest with socket visible in lateral view).

Female unknown, probably very similar to L. aequilimbata .

Type material. Holotype ♂ ( CNCI): CHILE, Reg. Coquimbo, Hacienda Illapel , 2,300–2,600 m, 20.xi.1954, L.E. Peña . Paratype ♂ ( CNCI): same data as holotype except 2,600 m .

Etymology. The species name refers to the long marginal scales of male sternite 5 (Lat. longus: long; limbatus: bordered) and alludes to the close relationship with L. aequilimbata .

Distribution. At present only known from the type locality in central Chile where it occurs at moderately high elevations (2,300 –2,600 m). The widespread Chilean species L. neocurvinervis is known from the same locality (see Material examined) but occurs at significantly lower elevations (600–1,200 m).

Discussion. This species is very close to L. aequilimbata . As discussed under the latter, L. aequilimbata shows considerable variation in the length of marginal scales of male sternite 5, one of the characters that separate the two species. We are nonetheless confident that L. longilimbata is in fact a good species because of additional surstylar differences (see Description) and because a male of L. aequilimbata from Jujuy Province, Argentina (the locality closest to the type locality of L. longilimbata sp.n.) has relatively short scales on sternite 5 (in L. aequilimbata the longest scales were found in specimens from Lake Titicaca, towards the northern end of its range).

Figures

FIGURES 76–79. Leptocera longilimbata sp.n. (Chile). Male terminalia (phallus and postgonites omitted): (76) lateral; (77) posterior; (78) ventral; (79) sternite 5. cp—finger-like process of cercus (omitted on left cercus), lp—lamellate process of cercus.

FIGURES 38–44. Leptocera aequilimbata (38–40: Argentina, 41–44: Bolivia). Male terminalia (phallus and postgonites omitted): (38) lateral; (39) posterior; (40) ventral, right cercus omitted; (41) sternite 5. Female terminalia: (42) dorsal; (43) spermathecae; (44) ventral. aps—anterior process of anterior section of surstylus, cb—cruciate bristles, ce—cercus, cp—finger-like process of cercus, ep—epandrium, fm—field of dense microtrichia, ha—hypandrial apodeme, hy—hypandrium, lp—lamellate process of cercus, pa—phallapodeme, proc—process at base of posterior section of surstylus, pss—posterior section of surstylus, S—sternite, sc—enlarged scales, se—subepandrial sclerite, T—tergite (female tergite 8 divided into two halves), vap—ventral appendage of tergite 8, vls—ventral lobe of anterior section of surstylus.