Microteroschema Eya, 2024

Microteroschema Eya , new genus

Type species. Microteroschema parvum Eya , new species

A new genus Microteroschema is created to include Microteroschema parvum new species and Microteroschema pseudolaetum new species.

Description. Form small, stout, sides subparallel. Head with front short, declivous, mid-cranial sulcus (median line) narrow, canaliculate, extending from postclypeus to posterior margin of antennal tubercles, each side above postclypeus below antennal insertion with a small pit, frontoclypeal sulcus transversely, shallowly excavated between pits; postclypeus declivous, subparallel with front ( Fig. 434 View Figures 428–439 , 446, 450 View Figures 440–458 ); genae short ( Fig. 433 View Figures 428–439 , 445, 449 View Figures 440–458 ); palpi short, subequal, last segments not expanded, apices truncate or rounded, dorsoventrally flattened, outer margin vaguely impressed; mandibles prominent, extended forward, sides arcuate from base to apex, dorsum with outer edge vaguely impressed; apices simple, not emarginated; eyes moderately large, finely faceted, upper lobes small, well separated, lower lobes large; antennal tubercles divergent; integument between tubercles impressed; antennae elongate, 11-segmented, 11 th antennomere slender, vaguely to non-appendiculate. Pronotum as broad as long to slightly broader, cylindrical, narrower than base of elytra at humeri, sides vaguely rounded, unarmed; apex narrower than base, apical margin without lateral collar-like projection ( Fig. 435 View Figures 428–439 , 447, 451 View Figures 440–458 ); prosternum with intercoxal process narrower than procoxal cavities, level with procoxae to slightly impressed below coxae, coxal cavities wide open behind; mesosternum with intercoxal process level with coxae, gradually declivous anteriorly ( Fig. 436 View Figures 428–439 , 452, 453 View Figures 440–458 ); posterior-lateral margins lobed, slightly overlapping mesocoxae. Scutellum triangular, as broad as long. Elytra with apices truncate or rounded; each elytron with one or two, longitudinal, glabrous, raised ivory-like vittae. Legs moderately short; metafemora falling far short of elytral apices in both sexes; metatarsomere I shorter than or subequal to tarsomeres II and III combined ( Fig. 438–439 View Figures 428–439 , 457–458 View Figures 440–458 ). Abdomen normally segmented. The following species are included in this genus: Microteroschema parvum Eya new species ( Fig. 428–439 View Figures 428–439 ) and M. pseudolaetum Eya new species ( Fig. 440–458 View Figures 440–458 ).

Discussion. Microteroschema new genus is introduced to include the “smaller form” of trachyderines with non-protuberant mesosternal intercoxal process, which do not fit the descriptions of either Mannophorus LeConte , Ischnocnemis Thomson or Paramannophorus Eya new genus. Microteroschema is characterized by the following combinations of characters: (1) smaller, stouter form (8–13 mm); (2) front that is declivous with antennal tubercles divergent with the integument between tubercles impressed forming a V-shaped valley sloping down to mid-cranial sulcus ( Fig. 432–434 View Figures 428–439 , 444–446, 448–450 View Figures 440–458 ); (3) mandibles and genae that are prominent, extended forward ( Fig. 433 View Figures 428–439 , 445, 449 View Figures 440–458 ); (4) mesosternal intercoxal process that is level with mesocoxae and declivous anteriorly ( Fig. 436 View Figures 428–439 , 452–453 View Figures 440–458 ); (5) short and stout metatarsi with tarsomere I shorter than tarsomeres II and III combined ( Fig. 438–439 View Figures 428–439 , 457–458 View Figures 440–458 ). The two species currently included in this genus have broad, ivory, subsutural vitta(e) on each elytron, carinate and rugosely punctate basal antennomeres, and carinate or coarsely,

rugosely, striate-punctate meso- and metatibiae.

Microteroschema do not have the lateral collar-like projection on the apical margin of pronotum as found in Mannophorus despite of its morphological similarity of the head capsule with prognathous mouthparts, declivous front, and divergent antennal tubercles. Also, Microteroschema and Mannophorus laetus LeConte have in common the shorter, stouter body form, and short tarsomeres of metatarsi. The species included in Ischnocnemis have front that is subvertical to vertical, and mandibles that are retracted and usually angulated near base. Ischnocnemis species also have a more elongate body form with elytra that are usually about three times as long as wide, and elongate and narrower metatarsi. Paramannophorus differs from Microteroschema as follows: (1) pronotum that is angulated on sides and narrowed apically with disc coarsely punctate, and densely clothed with long, erect setae; (2) genae with dorsal half narrow between margins of lower eyes and base of mandibles, and ventral half triangular; (3) basal antennomeres and meso- and metatibiae that are coarsely punctate without carina; and (4) distal antennomeres of female that are cylindrical not flattened and angulate apically. Microteroschema has pronotum that is slightly rounded on sides with disc finely punctate, and sparsely pubescence; genae with dorsal half broader with anterior margins of lower eyes well separated from the base of mandibles; dorsum of basal antennomeres, and meso- and metatibiae that are carinate or coarsely, rugosely, striate-punctate.

Etymology. The name Microteroschema μιΚρότερος refers to (“mikróteros”, smaller) and σΧήμα (“schema”, shape or form) or “smaller form” in Greek. Microteroschema with a “- schema ” ending is a gender-neutral generic name.