Macgrathphora, Brown, 2022

Brown, Brian V., 2022, Two new genera of phorid flies, Macgrathphora and Aurisetiphora, from Costa Rica (Diptera: Phoridae), with recommendations for naming new genera in the family, Zootaxa 5115 (4), pp. 571-581 : 573-574

Macgrathphora new genus

Figs. 1–3 , 5–9 , 11–13

Type species: Macgrathphora caribbea Brown (here designated).

Diagnosis. Metopininae (anepisternum divided, midtibia without isolated setae, epandrium and hypandrium fully separate). Four proclinate supra-antennal setae present. Notopleural cleft fringed with long microtrichia present. Hind tibial setal palisade and posterodorsal setal row (found in species of Megaselia and many similar genera) absent. Differing from Metopina -group genera (sensu Brown 1992), by the largely symmetrical male terminalia and presences of wing vein R 2+3. Differs from virtually all other metopinine phorids by the inflated Rs (especially in females) and the strongly downward pointing male cercus. In the key of Disney (1994) to phorid genera of the world, it runs to couplet 186, where it matches neither option ( Woodiphora Schmitz and Beckerina Malloch ). In the key of Brown (2010) to Central American phorid genera, it runs to couplet 90, where it again can be distinguished from Woodiphora Schmitz and Gymnophora Macquart by the swollen Rs vein and ventrally reflexed male cercus. All of these genera (and some others) share with Macgrathphora the presence of a notopleural suture or other notopleural gland opening, and thus might be part of a natural group.

General description. Body length 0.8–0.9 mm. Color light brown.

Head. Frons short, ocellar triangle disproportionally large. Distinct frontal furrow present. Frontal setation consists of usual 12 setae in 3 rows (4-4-4), with 4 subequal supra-antennal setae; dorsal and ventral interfrontal setae medioclinate. First flagellomere rounded, enlarged, with several subcuticular pit sensilla; arista dorsal. Palpus small.

Thorax. Scutal setulae sparse. Anepisternum divided, bare. Two notopleural setae present. Small to large notopleural cleft with fringe of long microtrichia present in males only. Scutellum with two pairs of subequal setae.

Wing. Sc well-developed, fusing with R 1 at the latter’s midlength. Rs inflated, thick, especially in females. R 2+3 present.

Legs. All legs with sparse, light-colored setulae; lacking enlarged setae, longitudinal setal palisades, and setal rows.

Abdomen. Dufour’s mechanism not observed. Tergites large, unmodified in both sexes.

Male terminalia. Epandrium short, triangular; cercus pointing ventrally.

Female terminalia. Large tergites present on segments 1–6 and posterior segments not modified into a parasitic ovipositor.

Derivation of name. The genus is named for Frank McGrath, a bodybuilder who has exceptional vascularity (and thus inflated veins). Latinization of McGrath requires the insertion of an “a” between the “M” and “c”.

Included species. From examination of the material at hand, it appears that there are at least three species of this genus in Central America and northern South America.

Natural history. Unknown.

Figures

FIGURES 1–4. Habitus, male, lateral. 1. Macgrathphora caribbea new species. 2. Macgrathphora longifurca new species. 3. Macgrathphora pacifica new species. 4. Aurisetiphora maggiesnowae new species.

FIGURES 5–10. Wing male. 5–6. Macgrathphora caribbea new species. 5. Male. 6. Female. 7–8. Macgrathphora longifurca new species. 7. Male. 8. Female. 9. Macgrathphora pacifica new species, male. 10. Aurisetiphora maggiesnowae new species, male.

FIGURES 11–14. Male genitalia, left lateral. 11. Macgrathphora caribbea new species. 12. Macgrathphora longifurca new species. 13. Macgrathphora pacifica new species. 14. Aurisetiphora maggiesnowae new species.