Panamamyia silbergliedi, Woodley, 2008

Woodley, Norman E., 2008, Two new Stratiomyinae, including Panamamyia gen. nov., from the Neotropical Region (Diptera: Stratiomyidae), Zootaxa 1701 (1), pp. 29-39 : 37-39

Panamamyia silbergliedi sp. nov.

( Figs. 8–17 )

Diagnosis. Panamamyia silbergliedi is the only known species in the genus. It may be separated from other Neotropical Stratiomyinae by the characters noted in the generic diagnosis.

Description. Male. Head dark yellowish with upper occiput, ocellar tubercle, and dorsal part of frontofacial prominence black, lateral margins of face sometimes with vague darkened areas. Pale yellowish pilosity extremely short and sparse, most easily visible on lower gena and lower occiput; some very short dark hairs present posterior to ocellar tubercle and along upper frons. Little tomentum present except on posterior surface of head where it is grayish. Antenna dark yellow, last three flagellomeres very slightly darkened, scape and pedicel with short blackish hairs. Labella shiny black, sharply pointed apically ( Figs. 9, 10 ), with very short, sparse pilosity; remainder of proboscis yellowish. Palpus pale yellow.

Thorax dark yellow with most of scutum and basal part of scutellum dull black, and subscutellum and central part of mediotergite brownish; pleura with vague pale greenish areas. Scutum and disc of scutellum with surface densely granulate. Scutum with short, inconspicuous appressed pilosity, lateral margins of scutum and scutellum with more erect, longer golden hairs; postalar wall and scutellum with black, slightly scale-like setae. Pleura with golden pilosity that is longest and most easily viewed on posterior half of anepisternum, anterior part of anepimeron, and lateral part of laterotergite, the last also with a few dark hairs. Legs dark yellow with extreme apices of femora blackish and tarsi with tarsomeres 3-5 brownish; legs with inconspicuous pale pilosity, longest and most easily visible on posterior faces of mid and hind femora. Wing ( Fig. 9 ) with even light brown infuscation, but apex paler (visible to the naked eye); wing virtually bare of microtrichia. Calypters dark infuscated with dark hairs along margins. Halter with knob dark brownish, stem dark yellow.

Abdomen ( Figs. 8, 9 ) completely dark yellow except for small dark more or less triangular spot at apex of fifth tergite, and small sixth tergite darkened; entire dorsum appearing brownish due to dense, evenly distributed vestiture of black, slightly scale-like hairs. Sternites with very short, inconspicuous, semi-appressed pale pilosity. Terminalia with gonocoxites ( Fig. 14 ) tapering anteriorly and with lateral margins rounded; gonocoxal apodemes short, near middle of gonocoxites and directed anteromedially; apex of hypandrium slightly produced, rounded posteriorly. Gonostylus arcuate, apex acute. Phallic complex ( Figs. 15, 17 ) trifid with median lobe parallel-sided, slightly rounded at apex, and longer than lateral lobes which are tapered posteriorly; attachment structure reduced medially. Epandrium ( Fig. 16 ) convex, subquadrate with rounded corners.

Length 9.8-10.2 mm.

Female. Differs from male as follows: Head with yellow coloration on lower part paler than that on dorsal areas; dorsal part of vertex behind medial eye margin vaguely infuscated with brown. Tiny silvery tomentose spot present just dorsal to anteriormost point of eye.

Thorax with pilosity on scutum paler, concentrated into a pair of submedial longitudinal vittae; without longer golden hairs at lateral margins; postalar wall with pilosity less conspicuous, mostly pale; pilosity of pleura shorter, less erect. Legs with darkened tarsomeres more blackish in color. Halter knob dull greenish.

Abdominal tergites dark brown with pale narrow lateral margins. Cercus with apical segment short ovoid, about two-thirds length of basal segment, dark brown.

Length 10.3 mm.

Specimens examined. Holotype ♂, PANAMA: Canal Zone , Barro Colorado Island, 15 July 1978, N. E. Woodley, at light ( USNM) . Paratypes: 1♂, same data as holotype ( USNM) ; 1♀ same data except 10 July 1978, and not collected at light ( USNM) .

Etymology. The species epithet is dedicated to Robert Silberglied (1946-1982), my first advisor at Harvard University who encouraged and facilitated my summer stay on Barro Colorado Island in 1978.

Remarks. This new genus is somewhat enigmatic among Stratiomyini because it has antennal structure that is similar to Odontomyia and related genera that have six distinct flagellomeres, but its general appearance is more similar to species of Promeranisa Walker and Rhingiopsis Röder. However , both of these genera have the antennal flagellum with five flagellomeres.

During a three month stay on Barro Colorado Island , Panama from late May to early September in 1978, I collected the three specimens of the type series over a short six day period in July. I have not seen any additional specimens despite having sorted through hundreds of Costa Rican Malaise trap samples from low elevation localities and sorted the entire stratiomyid collection at INBio. It is possible that the species is associated with canopy tree holes or some other limited habitat. Another Neotropical stratiomyine genus, Zuerchermyia Woodley , has larvae that are found in tree holes ( Yanoviak, 2001) and adults are quite rare in collections .

Figures

FIGURES 8–10. Panamamyia silbergliedi, gen. nov., sp. nov., male holotype. 8, dorsal view. 9, lateral view. 10, head and antennae, lateral view.

FIGURES 11–13. Panamamyia silbergliedi, gen. nov., sp. nov., female paratype. 11, dorsal view. 12, lateral view. 13, dorsolateral view of head and antennae.

FIGURES 14–17. Panamamyia silbergliedi, gen. nov., sp. nov., male terminalia of holotype. 14, genital capsule, dorsal view. 15, phallic complex, dorsal view. 16, epandrium and post-genital structures, dorsal view. 17, phallic complex, lateral view.