Tristria, Hołyński, 2001

Hołyński, Roman B., 2001, Two new genera of the subtribe Psilopterina Lac. (Coleopteraz Buprestidae) Abstract: The paper gives the description of two new genera of the subtribe Psilopterina LAC. from the Indo-Pacific Region., Annals of the Upper Silesian Museum (Entomology) 10 - 11, pp. 129-133 : 132-133

Tristria g.n.

Type species

Dicercomorpha cupreomaculata SAUNDERS 1867

General characteristics

Front flat; trapezoidal, not separated from epistome; sculpture consists of network of very prominent, sharply elevated, predominantly longitudinal smooth ridges and very densely but rather coarsely punctured depressions between them; periocular stripes not distinctly developed; no perceptible pubescence; vertex rather wide; eyes prominent, ca. 2x longer than wide.

Pronotum wide; sides slightly, almost straightly convergent in basal half and much more strongly, roundedly so before midlength. Disk convex, prebasal depression inappreciable, lateral carina very irregular but traceable almost to apex; base with deep punctiform fovea near each posterior angle; median line deeply, narrowly furrowed and densely, finely punctulate; broad space on each side of median furrow smooth, elevated, coarsely and very sparsely punctured; lateral parts with rather irregular, large elevated reliefs and dense fine punctulation in between. Scutellum relatively large, trapezoidal, much wider than long, convex.

Elytral sides obliquely truncated at humeri, then subparallel to midlength, strongly arcuately convergent to 6/7 and deeply sinuate before apices; lateral margin smooth; external apical denticle sharp, sutural not prominent. Each elytron with six (1 sutural, 4 discal, and 1 marginal) elevated costae, separated with 1, 2, 2, 2, and 2 interstriae (i.e. each discal intercostal area with 3 instead of usual 2 striae); striae not continuously depressed, consist of dense rows of coarse punctures; interstriae (including costae) interrupted here and there with small foveae.

Anterior margin of prosternum deeply arcuately emarginated between two prominent denticles; prosternal process ( fig. 2 ) almost parallelsided to behind procoxae, then sinuately narrowed to broadly rounded apex; deep lateral furrows extend to apex but remain separate, both narrow lateral rims and 4x wider median space absolutely smooth. Hind margin of metacoxae with but broadly rounded obtuse tooth at medial third. 1. sternite convex, median depression represented only by row of punctures on (otherwise smooth) intercoxal process, rest of surface - like that of segments 2-4 - very densely and regularly, finely punctulate with some smooth elevated reliefs at sides; anal sternite coarsely and less densely punctured, truncate apically.

Remarks

The type-species of this subgenus used to be placed in Dicercomorpha DEYR. ; however, structure and ornamentation of elytra, striatomarginate prosternal process, sulcate median line of pronotum, additional striae on elytra, and some other peculiarities make its separation at generic level warranted.

The name Tristria is feminine.

Figures

Fig. 2. Tristria cupreomaculata (SND.) - prosternat process.