Trilobitofoenus Macedo

Macedo, Antonio Carlos Cruz, 2009, Generic classification for the Gasteruptiinae (Hymenoptera: Gasteruptiidae) based on a cladistic analysis, with the description of two new Neotropical genera and the revalidation of Plutofoenus Kieffer, Zootaxa 2075, pp. 1-32 : 19-20

Trilobitofoenus Macedo n. gen.

( Figs. 5 , 6g , 7 g –h, 8b, 11i –n, 12e–g, 13g –i, 14f, 15)

Type species. Trilobitofoenus plaumanni Macedo.

Etymology. The name of the genus is derived from Trilobite, because of the mesoscutum sculpture, which in dorsal view, gives to the wasp the appearance of a trilobite ( Figs. 12 e–g). The gender is masculine. Description. Body length between 10.0–15.0 mm (exclusive of ovipositor).

Head. Subtrapezoidal in dorsal view ( Figs. 11 i, 11k, 11m); mandible in frontal view with apex acute; malar space short, almost disconnected from gena ( Figs. 11 j, 11l, 11n); clypeus with a longitudinal ridge ( Fig. 6g ); clypeus and face without longitudinal striae; occipital margin simple ( Figs. 11 i, 11k, 11m).

Mesosoma. Pronotum with three lobes well defined ( Figs. 13 g-i); pronotal process absent ( Figs. 13 g-i); propleuron collar shaped anteriorly ( Fig. 8 b); mesonotum rounded in lateral view ( Figs. 13 g-i); mesoscutum with anterior portion rather smooth and posterior portion rugose or striate, as long as wide, and forming two different planes separated by depressed notauli, parapsides distinct ( Figs. 12 e-g); mesepimeron with a dorsal ridge ( Figs. 13 g-i); fore and middle tibiae uniformly colored; hind tibia entirely black to dark brown; metacoxa rather smooth at posterior portion ( Fig. 14 f); median propodeal carina flattened, either present at anterior half, or absent; fore wing jugal lobe present; discal cell present (subtriangular) ( Fig. 7 g) or absent ( Fig. 7 h), vein r–m present (spectral) or absent, fore wing vein 2–M tubular in 1st 1/3 and spectral in remaining portion ( Fig. 5a ); hind wing with 3–5 equidistant hamuli ( Fig. 5a ).

Metasoma. First metasomal tergum with edges separate, not concealing 1st sternum; female subgenital sternum with a slitlike Y-shaped notch (as Fig. 10 a); ovipositor longer than T2+T3 and shorter than metasoma ( Fig. 5 ).

Distribution. Neotropical: Mexico (Chiapas), Guatemala, Brazil (Amazonas and Santa Catarina). Trilobitofoenus shows a more widespread distribution range than the other two exclusively Neotropical genera, occurring between 15ºN and 27ºS ( Fig. 15 ). Species occur in tropical rainforests (southern Mexico, Guatemala, and Amazon) and in an area originally occupied by a subtropical conifer forest in southern Brazil.

Biology. Unknown.

Comments. There is scarce material of this genus, with each species recorded for only one or two localities.

Figures

FIGURE 8. Propleuron in ventral view. a: Gasteruption bispinosum; b: Trilobitofoenus plaumanni. Without scale. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 10. Subgenital sternum in ventral view. a: notched, Y-shaped; b: notched, V-shaped; c: simple. Without scale. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 11. Head in dorsal and lateral views. a – b: Plutofoenus chaeturus; c – d: P. e d w a rd s i; e – f: P. paraguayensis; g – h: Spinolafoenus ruficornis; i – j: Trilobitofoenus alvarengai; k – l: T. plaumanni; m – n: T. sericeus. Scale bar: 1.0 mm. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 12. Mesonotum in dorsal view. a: Plutofoenus chaeturus; b: P. e d w a rd s i; c: P. paraguayensis; d: Spinolafoenus ruficornis; e: Trilobitofoenus alvarengai; f: T. plaumanni; g: T. sericeus. Scale bar: 1.0 mm. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 13. Mesosoma in lateral view. a: Gasteruption bispinosum; b: G. guildingi; c: Plutofoenus chaeturus; d: P. edwardsi, e: P. paraguayensis; f: Spinolafoenus ruficornis; g: Trilobitofoenus alvarengai; h: T. plaumanni; i: T. sericeus. Scale bar: 1.0 mm. Lobes of pronotum: vl: ventral lobe; dl: dorsal lobe; ll: lateral lobe. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 14. Propodeum and metacoxa in dorsal view. a: Gasteruption bispinosum; b – c: Plutofoenus edwardsi; d: Gasteruption sp. I; e: Spinolafoenus ruficornis; f: Trilobitofoenus plaumanni. Scale bar: 1.0 mm. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 15. Geographic distribution of the species of Plutofoenus, Spinolafoenus and Trilobitofoenus.

FIGURE 5. a – b: Trilobitofoenus plaumanni habitus. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 6. a – g: Head in anterior view. a: Aulacus sp. A; b: Pseudofoenus infumatus; c: Gasteruption bispinosum; d: G. nasutum (without scale); e: Plutofoenus edwardsi; f: Spinolafoenus ruficornis; g: Trilobitofoenus plaumanni; h – i: Left mandible in frontal view (without scale). h: G. bispinosum; i: Plutofoenus edwardsi. Scale bar: 1.0 mm. Numbers indicate characters and respective synapomorphic states (within brackets).

FIGURE 7. a – b: Left fore wing (scale bar: 1.0 mm). a: Pseudofoenus infumatus; b: Gasteruption bispinosum; c – h: Left fore wing discal cell (without scale); c: G. bispinosum; d: G. p a r v u m; e: Plutofoenus edwardsi; f: Spinolafoenus ruficornis; g: Trilobitofoenus plaumanni; h: T. alvarengai. Numbers indicate characters and respective synapomorphic