Penthetria dolichopeza Fitzgerald, 2021

Fitzgerald, Scott J., 2021, Penthetria Meigen (Diptera: Bibionidae): Revision of the New World species and world catalog, Zootaxa 4926 (4), pp. 451-500 : 469-470

Penthetria dolichopeza Fitzgerald n. sp.

( Figs. 12–15 , 43 , Map 2 )

Type Material. Holotype: Male ( Figs. 12–15 ), point-pinned ( BYUC), COSTA RICA, San Jose, Nubes de Coronado, La Abigail , 5-V-1995, Baumann & Houseman [white label] / HOLOTYPE, Penthetria dolichopeza Fitzgerald [red label], terminalia dissected. Missing right front, right middle, and left hind legs. Paratype: MEXICO, Chiapas, Yerba Buena, Hwy 195, 10. VI .1969, B. V. Peterson , 1 male ( CNCI) .

Description. Male ( Fig. 12 ). Body length: approx. [7.0] mm. Head. Black. Compound eye holoptic, covering virtually all of dorsal and lateral surface of head, with lateral longitudinal step dividing upper and lower portion of eye. Eyes nearly bare, with some very minute, very sparse ommatrichia present.Antennae dark brown to black, eight flagellomeres with black setae. Flagellomeres wider than long except first flagellomere elongate, about three times as long as wide, apical flagellomere smaller. Three ocelli on well-developed tubercle. Thorax matte dark brown with light brown highlights on humeral ridge and posterior portions of pleura. Thorax largely bare except fine short dark hairs on scutellum and in broad dorsocentral rows. Legs. Slender elongate. Entirely dark brown with dense short dark appressed hairs. Hind femur gradually thickened (clavate) on apical half. Hind tibia slender elongate virtually parallel-sided. Hind basitarsus slender elongate, about twelve times as long as wide ( Fig. 12 , hb). Wings ( Fig. 13 ). [8.0] mm, evenly brown fumose except slightly darker costally. Veins brown, pterostigma concolorous with membrane. Sc long, complete. R 2+3 elongate, subparallel to R 4+5, without basal appendix. CuA reaching wing edge, CuA and CuP parallel apically, not distinctly convergent or meeting. Abdomen. Dark brown. Terminalia ( Figs. 14–15 , 43 ) dark brown to black. Tergite nine broader than long, posterior margin with very shallow v-shaped emargination on posterior edge ( Fig. 14 ). In dorsal view, gonocoxites dorsoapically with small apically rounded medially-projecting lobe just dorsal to gonostylar socket ( Fig. 14 , dal). In ventral view, posterior edge of medially fused gonocoxites + hypandrium medially flat, without additional median cleft or development of lobes ( Fig. 15 ). Gonostylus short stout gently curved, apically broadly rounded expect for small thorn-like nub anteroapically ( Figs. 14–15 ). In dorsal and ventral views, fused parameres projecting from out of genital capsule, shiny brown heavily sclerotized, posteriorly rounded dome-like, but roughly triangular in overall shape (much broader anteriorly than posteriorly) ( Fig. 43 ). Cerci fleshy, apically rounded with setae.

Female. Unknown.

Diagnosis. This species can be distinguished from all other New World species by the very long slender hind basitarsus (about 12 times as long as wide ( Fig. 12 , hb)), the shape of the gonostylus (short, stout, gently curved, apically broadly rounded with small thorn-like nub anteroapically ( Figs. 14–15 )), the paramere is roughly triangular (much broader anteriorly than posteriorly) in dorsal view ( Fig. 43 ), gonocoxites dorsoapically with small apically rounded medially-projecting lobe just dorsal to gonostylar socket ( Fig. 14 , dal), ventromedian lobes of gonocoxites absent, and posterior edge of tergite with at most a very broad, shallow cleft.

Remarks. The form of the gonostylus and paramere in P. dolichopeza are unlike any other species in the Nearctic and Neotropical regions, though this gonostylar form is known in some Palearctic species such as P. motschulskii (Gimmerthal) from Russia & China (e.g., see Hardy & Takahashi 1960, Fig. 3b ) and P. funebris (Europe, Russia) and the roughly triangular paramere is very similar to that described for P. motschluskii ( Krivosheina 1999) .

While the female of P. dolichopeza is currently unknown, the similarities of the male terminalia to the aforementioned Palearctic species might provide clues to the structure of the female terminalia of P. dolichopeza ; females of both Palearctic species have female tergite nine in dorsal view medially divided, but represented by a significant pair of sclerotized plates. In the New World, only females of P. neonigrita have tergite nine strongly represented, though it occurs to a lesser degree in P. appendicula and P. distincta and is almost absent dorsally (represented by only a very thin strap) in the remainder of the species.

Etymology. The specific epithet is derived from the Greek dolichos (long) and peza (foot) for the long hind basitarsus of this species.

Geographic & Seasonal Distribution. Southern Mexico and Costa Rica ( Map 2 ). Seasonal distribution summarized in Table 1.

Figures

MAP 2. Distribution of P. arizonensis (black circle) and P. dolichopeza (white circle).

FIGURES 12–13. P. dolichopeza n. sp., holotype male. 12. Habitus, lateral. 13. Wing. Scale bars = ca. 1.0 mm. Abbreviations: hb, hind basitarsus.

FIGURES 14–15. P. dolichopeza n. sp., holotype, male terminalia. 14. Dorsal. 15. Ventral. Scale bar = ca. 0.5 mm. Abbreviations: c, cerci; dal, dorsoapical lobe of gonocoxite; gc, gonocoxite; gs, gonostylus; p, paramere; t9, tergite nine.

FIGURES 42–45. Male terminalia, dorsal, tergite nine removed. 42. P. distincta. 43. P. dolichopeza n. sp., paratype. 44. P. appendicula. 45. P. neonigrita n. sp., paratype. Scale bar = ca. 0.5 mm. Abbreviations: dlp, divergent lobes of paramere; ea, ejaculatory apodeme; ga, gonocoxal apodeme; gc, gonocoxite; gs, gonostylus; p, paramere; vml, ventromedian lobes of gonocoxite.

FIGURES 2–3. P. appendicula. 2. Wing. 3. Female habitus, lateral view. Scale bars = ca. 1.0 mm. Abbreviations: ba, basal appendix of R2+3; aem, anepimeron; aes, anepisternum; c, coxa; f, femur; h, halter; hb, hind basitarsus; kem, katepimeron; kes, katepisternum; m, meron; mtaes, metanepisternum; mtg, mediotergite; mtkes, metakatepisternum; ltg, laterotergite; pltrch, pleu- rotrochantin; prn, pronotum; sct, scutum; t, trochanter.