Eusphalerum margaretae Zanetti, 2014

Zanetti, Adriano, 2014, Taxonomic revision of North American Eusphalerum Kraatz, 1857 (Coleoptera, Staphylinidae, Omaliinae), Insecta Mundi 2014 (379), pp. 1-80 : 46

Eusphalerum margaretae Zanetti n. sp.

Material examined (1 specimen)

Holotype m Tennessee Sevier Co S. Gatlinburg 24.05.1977 leg. M. Thayer.

Measurements. Head length: 0.22; head width: 0.44; pronotal length: 0.44; pronotal width: 0.57; elytral length: 0.88; elytral width: 0.83; length (clypeus to apex of elytra): 1.69; total length: 1.8.

Etymology. The species, like E. thayeranum n. sp., is dedicated to its collector, Margaret K. Thayer, specialist of Staphylinidae Omaliinae .

Description. Habitus as in Fig. 130. Head, pronotum and elytra yellowish; abdomen brown, somewhat paler at apex; prosternum yellowish, metasternum brownish, legs yellowish; antennae yellowish, slightly darkened from antennomere 7.

Head with prominent eyes, postocular carina well marked; temples short, convergent caudad. Medial margin of eyes with microsculpture formed by meshes slightly lengthened, postantennal depression large not much deep, confluent with the rounded tentorial pits forming 2 superficial longitudinal depressions in front of ocelli, punctation very superficial and sparse, ground with isodiametric microsculpture, neck scarcely separated from head. Antennae rather short, antennomere 1 and 2 ovoid, 3 elongate, twice as long as wide, 4 and 5 longer than wide, 6 subquadrate, 7-10 transverse, 10 less than twice as wide as long, 11 twice as long as wide, cylindrical in the proximal part, conical at apex.

Pronotum not much convex, without impressions, transverse (ratio width/length = 1.45), widest slightly in front of middle, anterior margin slightly narrower than posterior, lateral margins rounded, posterior angles scarcely obtuse and well marked, punctation very sparse and superficial, surface with isodiametric microsculpture, pubescence extremely short, scarcely visible, depressions near posterior angles distinct, extending anterad in front of middle.

Elytra scarcely elongate (ratio length from scutellum to apex / combined width of elytra = 1.0), truncate at apex, clearly widened toward apex, punctation much stronger than on pronotum, irregular and scarcely confluent, ground glossy, pubescence extremely short and scarcely visible.

Abdomen rather glossy, microsculpture superficial, with decumbent pubescence.

Tibiae straight, not modified, tarsomere 5 of posterior tarsi as long as 1-4 together.

Aedeagus as in Fig. 131, internal sac with 2 short spines.

Female unknown.

Comparative notes. Eusphalerum margaretae is close to E. thayeranum , which has different shaped spines in the internal sac of the aedeagus. It is also similar to E. fenyesi , but the latter lacks the spines of the internal sac. The unique known specimen has a brown metasternum (yellowish in E. thayeranum ). Eusphalerum orientale is distinguished by the even more sparse and superficial punctation of the pronotum, and by the presence of 2 rows of fine spines in the internal sac of the aedeagus.

Distribution. UNITED STATES: Tennessee (Map 3).

Natural history. The specimen was collected in May.