Allotrichoma slossonae Cresson 1942

Allotrichoma (Pseudohecamede) slossonae (Cresson)

Allotrichoma slossonae Cresson, 1942:108 [Florida].

Pseudohecamede slossonae.—Wirth, 1965:737 [generic combination].

DESCRIPTION.—Moderately small shore flies, length 2.30 to 2.95 mm. Head: Proclinate fronto-orbital seta present, subequal in length to reclinate seta; pseudopostocellar setae present, about 3A length of ocellar setae. Arista with basal thickened portion short, about 1h total aristal length; arista bearing 4–5 dorsal rays, basal 3 subequal in length. Face of female bicolored, silvery colored on ventral V2, concolorous with gena, brown dorsally, concolorous with frons; face of male more unicolorous, brown, concolorous with frons; lower facial margin shallowly emarginate.

Thorax: Presutural seta present, subequal to larger postpronotal seta; acrostichal setulae in 4–6 rows anteriorly, lateral rows with fewer setulae; mesonotum and dorsal portion of anepisternum brown, coloration more or less uniform, some specimens with slightly darker coloration through setal tracks; a horizontal, light silvery gray stripe from postpronotum through ventral portion of notopleuron; dorsal xh of anepisternum light brown, otherwise pleural areas silvery gray. Wing milky white; veins pale colored, costal vein yellowish, those behind whitish; costal vein ratio 0.43; M vein ratio 0.46. Legs, except for tarsi, grayish to grayish brown; tarsi with basal 1–2 tarsomeres yellowish, apical 1–2 grayish brown.

Abdomen: Second tergum very lightly grayish brown; other terga silvery gray. Male terminalia (Figure 25) as follows: Epandrium in lateral view well developed dorsally, distinctly tapered ventrally, and posteroventral angle little produced; cercus well developed, width obviously greater than that of epandrium; surstylus moderately well developed comparatively, length less than width of cercus, apex pointed; aedeagal apodeme with basal portion large, irregularly shaped, with a short posterior projection, which attaches to the hypandrium, and a short dorsal projection, which attaches to the base of the aedeagus; aedeagus simple, dorsal surface slightly sinuate, and with preapical enlargement, apex narrowly rounded; gonite as an irregular triangle, posteroventral angle well developed, robust, anterodorsal surface shallowly concave; hypandrium in lateral view angulate, ventral arm longer but no more robust than dorsal arm.

TYPE MATERIAL.—The holotype female is labeled “BISC[ayne] BAY, FL[orid]A./Mrs. [A.T.]Slosson Collector/Type No. 56367 U.S.N.M. [red]/Pseudohecamede slossonae Cress, [red, handwritten]/Published as Allotrichoma slossonae Crcsson [white, handwritten].” The holotype is point mounted, is in fair condition (much of the left side of the thorax is obscured by the glue and tip of the paper point), and is in the Smithsonian Institution, National Museum of Natural History (USNM).

OTHER SPECIMENS EXAMINED.—CHILE. Antofagasta: San Pedro Atacama (2280 m), 1–5 May 1964, L.E. Peña (I9; CNC).

ECUADOR. Manabi: Bahia, 10 Jan 1978, W.N. Mathis (16, 10; USNM).

MEXICO. Chiapas: Boca de Cielo (17 km S Puerto Arista), 18 May 1985, W.N. Mathis, A. Freidberg (3, 3; USNM); Puerto Arista, 18 May 1985, W.N. Mathis, A. Freidberg (1; USNM). Tabasco: Paraíso (5 km E), 6 May 1985, W.N. Mathis, A. Freidberg (3, 5; USNM).

PANAMA. Canal Zone: Mojinga Swamp, Fort Sherman, Jan 1953 (1; USNM). Darien: Jaque, 24 Jul 1952, F.S. Blanton (1; USNM). Panama: San Carlos, 17 Sep 1952, F.S. Blanton (1; USNM); Vique Cove, 7 Oct 1952, F.S. Blanton (1; USNM).

UNITED STATES. Florida: Dade Co., Biscayne Bay, A.T. Slosson (1; USNM).

WEST INDIES. DOMINICA. Cabrits (swamp), 22 Mar 1989, W.N. Mathis (1, 2; USNM); Calibishie, 22 Mar 1989, WN. Mathis (1; USNM); Layou River (mouth), 6 Feb 1965, W.W. Wirth (3; USNM); Rosalie, 23 Mar 1989, W.N. Mathis (3, 39; USNM).

DISTRIBUTION (Figure 26).—Chile, Ecuador, Mexico, Panama, United States (Florida), and the West Indies (Dominica and St. Vincent).