Baconia disciformis, Caterino, Michael S. & Tishechkin, Alexey K., 2013

Caterino, Michael S. & Tishechkin, Alexey K., 2013, A systematic revision of Baconia Lewis (Coleoptera, Histeridae, Exosternini), ZooKeys 343, pp. 1-297 : 41-42

Baconia disciformis sp. n. Figs 9 A–DMap 2

Type locality.

FRENCH GUIANA: Belvèdére de Saül [3.01°N, 53.21°W].

Type material.

Holotype female: "GUYANE FRANÇAISE: Belvèdére de Saül, point de vue. 3°1'22"N, 53°12'34"W. Piège vitre 20.xii.2010. SEAG leg." / "Caterino/Tishechkin Exosternini Voucher EXO-01292" (MNHN).

Diagnostic description.

Length: 2.6mm, width: 2.5mm; body broadly subquadrate, strongly depressed, glabrous; dorsum uniformly metallic blue, venter piceous; frons depressed at middle, interocular margins weakly convergent dorsad, coarsely punctate throughout, more densely toward vertex, frontal stria present along inner margin of eye, absent across front, supraorbital stria absent; antennal scape short, club distinctly elongate, sides subparallel; epistoma transversely elevated along apical margin; labrum about 3 ×wider than long, apically emarginate; both mandibles with basal tooth, that on right mandible rather weak; pronotal sides almost evenly arcuate to apex, lateral marginal stria complete around lateral and anterior margins, close to margin and non-crenulate, submarginal stria absent; pronotal disk rather linearly depressed along anterior third of lateral margin, with only fine ground punctation over median three-fourths of disk, with small, shallowly impressed secondary punctures interspersed at sides; elytra with two complete epipleural striae, outer subhumeral stria absent, inner nearly complete, only slightly abbreviated apically, dorsal stria 1 complete, 2nd stria obsolete in basal third, 3rd stria very fine, scratchlike, present in basal half only, 4th, 5th and sutural striae absent, elytral disk with very small secondary punctures just along apical margin; prosternal keel broad, flat, base more or less truncate, carinal striae complete, separate, weakly convergent anterad; prosternal lobe about two-thirds keel length, apical margin narrowly rounded, marginal stria present obsolete at sides; mesoventrite broadly and weakly emarginate, marginal stria interrupted for width of prosternal keel; mesometaventral stria absent, though suture is evident, arched anterad, inner lateral metaventral stria originating close to mesocoxa, curving posterolaterad toward outer corner of metacoxa, recurved mediad at apex, outer lateral metaventral stria present, close and parallel to inner stria for about two-thirds its length, metaventral disk impunctate at middle; abdominal ventrite 1 with complete inner lateral stria and posterior fragment of outer stria, disk impunctate between; protibia narrow, elongate, with three well developed marginal teeth, outer margin very finely serrulate between; mesotibia with single, inconspicuous submarginal spine; outer metatibial margin smooth; pygidia short and wide, propygidium without transverse basal stria, small secondary punctures concentrated along base and at sides; propygidial gland openings very small, located about one-third from anterior margin, and one-fifth from lateral corner; pygidium with sparse ground punctation and small secondary punctures evenly, sparsely interspersed. Male: not known.

Remarks.

This species is second in size only to Baconia loricata , but is still significantly smaller than that species. It may be further distinguished by its lack of transverse propygidial stria, densely punctate frons, and elongate legs, particularly the protibia (Figs 9 A–D).

Etymology.

This species’ name refers to its large, flattened disc-like body.