Allotrichoma (Neotrichoma) insulare, Mathis, Wayne N. & Zatwarnicki, Tadeusz, 2012

Mathis, Wayne N. & Zatwarnicki, Tadeusz, 2012, Revision of New World Species of the Shore-fly Subgenus Allotrichoma Becker of the Genus Allotrichoma with Description of the Subgenus Neotrichoma (Diptera, Ephydridae, Hecamedini), ZooKeys 161, pp. 1-101 : 75-77

Allotrichoma (Neotrichoma) insulare sp. n. Fig. 8690

Description.

This species is distinguished from congeners, especially those in Neotrichoma , by the following combination of characters: Minute to small shore flies, body length 0.86-1.35 mm. Head: Frons moderately 2-3-toned, mostly brown but with gray, microtomentose areas toward anterior apex of triangular mesofrons and at each posterior angle near vertex, whitish gray, microtomentose areas anteriorly on fronto-orbits; pseudopostocellar setae subequal in length to ocellar setae. Pedicel with well-developed, proclinate, dorsal seta. Facial coloration variegated from tan to gray to golden ventromedially; face with dorsal 2/3 between antennal grooves shallowly cari nate, becoming more prominent ventrad of facial grooves, slightly tuberculate; clypeus mostly bare, black, subshiny; maxillary palpus blackish.

Thorax: Mesonotum generally brown with gray stripe anteriorly on either side of acrostichal setulae and more faintly through portion of dorsocentral track; chaetotaxy generally well developed; prescutellar acrostichal setae much larger than other acrostichal setulae and more widely set apart; presutural supra-alar seta well developed, length subequal to notopleural setae; katepisternum with 2 setae, 2nd seta smaller and inserted below larger seta. Wing mostly hyaline; veins behind costa brownish; alular marginal setulae short, less than 1/2 alular height; costal vein ratio 0.41-0.55; M vein ratio 0.44-0.45. Legs: tibiae dark, concolorous with femora.

Abdomen: Abdomen shiny, sparsely microtomentose, black; 5th tergite short, length less than 1/2 4th; 5th sternite unmodified, lacking ventral process, transversely narrow, shallowly arched, bearing numerous setulae. Male terminalia (Figs 86-89): Epandrium in posterior view (Fig. 86) uniformly and broadly U-shaped, in lateral view (Fig. 87) moderately narrow, height twice width, slightly curved anteriorly at ventral margin; cercus in posterior view (Fig. 86) becoming broader ventrally, ventral margin sinuous with a short, medial projection, dorsal margin pointed medially, in lateral view (Fig. 87) with anterior margin shallowly curved, posterior margin rounded, slightly narrower dorsally than ventrally; surstylus a rod-like, slender process that bears an apical, prominent setula; aedeagus in ventral view (Fig. 88) elongate, almost parallel sided, base rounded, apical 1/3 deeply cleft, in lateral view (Fig. 89) gently sinuous, slightly broader apically; phallapodeme in lateral view (Fig. 89) with relatively short keel, irregularly rounded, in ventral view (Fig. 88) rod-like, slightly broader basally; gonite in lateral view (Fig. 89) with basal margin broadly excavated, forming 2 processes, thereafter apically slightly angulate, broadly formed to broadly rounded apex that bears 3 setulae, in ventral view (Fig. 88) elongate, almost parallel sided, curved laterally; hypandrium moderately deeply emarginate along posterior margin, forming a receptacle for base of phallapodeme, longer than wide, anterior margin broadly rounded.

Type material.

The holotype male Allotrichoma insulare is labeled "DOMINICA. Cabrits [Swamp] (15°35'N, 61°29'W)[,] 19 June 1991[,] W. N. & D. Mathis /HOLOTYPE ♂ Allotrichoma insulare W. Mathis & T. Zatwarnicki USNM [red]/USNM ENT 00117963 [plastic bar code label]." The holotype is double mounted (minuten in a block of plastic), is in excellent condition, and is deposited in the USNM. Seven paratypes (3♂, 4♀; USNM) are as follows: DOMINICA. Macoucheri (seashore), 1 Feb 1965, W. W. Wirth.

Type locality.

Dominica. Cabrits Swamp (15°35'N, 61°29'W).

Other specimens examined from the New World.

GRENADA. St. John: Palmiste (12°08.7'N, 61°44.4'W), 21 Sep 1996, W. N. Mathis (1♀; USNM). St. Patrick: Bathway Beach (12°12.6'N, 61°36.7'W), 18-20 Sep 1996, W. N. Mathis (1♂; USNM).

Distribution.

(Fig. 90)Neotropical: West Indies (Dominica, Grenada).

Etymology.

The species epithet, insulare, refers to the island habitat of this species in the West Indies.

Remarks.

This species is distinguished from congeners, especially those in Neotrichoma , by the mostly dark brown mesonotum with faint grayish longitudinal stripes laterad of acrostichal setulae and a subshiny to shiny, blackish brown abdomen that is sparsely microtomentose.