Forcipomyia (Metaforcipomyia) rivalis, Spinelli, Gustavo R., Marino, Pablo I. & Borkent, Art, 2012

Spinelli, Gustavo R., Marino, Pablo I. & Borkent, Art, 2012, A revision of Biting Midges of the Subgenera Forcipomyia (Metaforcipomyia) and F. (Saliohelea) from Costa Rica (Diptera: Ceratopogonidae), Zootaxa 3419, pp. 1-52 : 7-9

Forcipomyia (Metaforcipomyia) rivalis n. sp.

( Figs. 11–17 , 140 )

Diagnosis. Male: only species of Neotropical Forcipomyia (Metaforcipomyia) with labrum truncate apically and a row of transverse elongate spicules, scutum pale and contrasting with the dark scutellum, parameres absent and the aedeagus with an slender posteriorly directed prong. Female: unknown.

Description. Male. Head. Brown. Eyes abutting medially for length of three ommatidia. Antenna ( Fig. 11 ) with plume setae poorly developed, flagellomeres 2–4 spherical, flagellomere 10 1.42–1.50 (1.45, n = 4) X longer than flagellomere 11, flagellomeres 10–13 elongate; flagellomere 13 with apical nipple, not constricted basally; AR 1.18–1.24 (1.20, n = 4). Palpus ( Fig. 12 ) with segment 3 swollen at midlength, with scattered sensilla on surface; PR 2.50–2.88 (2.71, n = 3). Labrum truncate apically with a row of transverse elongate spicules.

Thorax. Pale yellowish except scutellum and postscutellum brown; scutellum with 8 strong setae. Legs ( Fig. 13 ) light brown, basal 2/3 of fore femur, distal 2/3 of fore tibia, apex of hind tibia slightly darker; apex of hind tibia with 5–6 spines; tarsomeres 1–5 brown with pectinate scales; tarsomere 1 of foreleg with a row of spine-like bristles; tarsomere 1 of hind leg with patch of thick setae on basal portion; foreleg TR 1.75–2.00 (1.84, n = 4), midleg TR 0.83–0.91 (0.88, n = 4), hind leg TR 1.08–1.16 (1.12, n = 4); claws curved, moderately stout. Wing ( Fig. 14 ) plain, without pattern of pigmented membrane; M2 not visible; first radial cell obliterated; second radial cell well developed; fork of cubitus situated distad to level of apex of costa; CuA2 obsolete on distal 1/3; wing length 1.58–1.70 (1.67, n = 4) mm; breadth 0.52–0.58 (0.55, n = 4) mm; CR 0.37–0.39 (0.38, n = 4). Halter whitish.

Abdomen. Tergites pale brown with brownish lateral spots. Genitalia ( Fig. 15 ): Brown except gonostyli pale. Tergite 9 short, extending to 1/4 length of gonocoxite; posterior margin truncate; cercus lobe-like, slightly produced beyond midlength of gonocoxite; sternite 9 ( Fig. 16 ) broad, posterior margin nearly straight, with single row of five strong setae. Gonocoxite stout, 1.9 X longer than greatest breadth; gonostylus 0.85 length of gonocoxite, somewhat sinuous, tip pointed. Parameres absent, gonocoxal apodemes slightly curved. Aedeagus ( Fig. 17 ) stout, triangular, with posteriorly directed prong poorly defined distally; basal arch very low, extending 1/20 of total length; lateral arms extending laterally.

Female. Unknown.

Distribution. This species is known only from the Osa Península of Costa Rica at elevations of 300–495 meters ( Fig. 140 ).

Taxonomic discussion. This species is very similar to F. pluvialis which differs from this new species in having an irregularly shaped sensory pit on palpal segment 3, the base of the hind femur is dark and the aedeagus abruptly tapers to slender pointed tip. In addition, this species shares with F. truncata the presence of a transverse row of spicules on the labrum and has a similarly shaped aedeagus, but the pigmentation of the scutum of the latter species is uniformly as dark as that of the scutellum, and the basal arch of the aedeagus extends 1/10 of its total length.

Type material. Holotype male on microscope slide, labeled “ HOLOTYPE Forcipomyia (Metaforcipomyia) rivalis Spinelli, Marino and Borkent , Costa Rica, Puntarenas prov., Golfito, Corcovado NP, Estación Agujas, La Bonanza, 495 m, 15/V-15/VI-1999, J. Azofeifa, Malaise tp. LS276000 525500 #52741, CD 5179” ( INBC). Paratypes, 3 males as follows: same data as holotype, 1 male ( CNCI). Costa Rica, Puntarenas prov., Península de Osa, Río Agujas, Est. Agujas, Send. Purruja, 300 m, 10/ 20-VIII-1996, A. Azofeifa, Malaise tp., CD 5079, 1 male ( INBC). Costa Rica, Puntarenas prov., Pto. Osa, Est. Agujas, 300 m, 15-VII / 15-VIII-1999, J. A. Azofeifa, CD 5089, 1 male ( INBC).

Derivation of specific epithet. The name rivalis (competitor) refers to the contrasting pigmentation between the pale scutum and dark scutellum of the male of this species.

Figures

FIGURES 11 – 17. Forcipomyia (Metaforcipomyia) rivalis sp. n., male. 11 — flagellum; 12 — palpus; 13 - legs (lateral view); 14 — wing; 15 — genitalia (ventral view); 16 — 9 th sternite; 17 — aedeagus.

FIGURES 140 – 141. Distribution map of species of Forcipomyia (Metaforcipomyia).