Baconia incognita, 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 : 112-114

Baconia incognita sp. n. Figs 32C33 G–KMap 9

Type locality.

PERU: Loreto: Rio Nanay [3.90°S, 73.55°W].

Type material.

Holotype male: "PERU: Loreto 45 km W Iquitos, Rio Nanay, Porvenir 3°54'S, 73°33'W White sand, piège vitre. 20.vi.2011 G.Lamarre. P3 V1 WS" / "Caterino/Tishechkin Exosternini Voucher EXO-02503" (MNHN).

Diagnostic description.

Length: 1.4mm, width: 0.9mm; body elongate, parallel-sided, weakly depressed, glabrous; color rufescent, shining; head with frons slightly elevated over antennal bases, weakly depressed at middle, interocular margins convergent dorsad, frontal punctation moderately coarse, finer and sparser toward epistoma, frontal stria absent, supraorbital stria vaguely represented by few confluent punctures; antennal scape short, club short, rounded; epistoma truncate; labrum about 3 × wider than long, apical margin emarginate; mandibles short, each with median tooth; pronotum with sides subparallel in basal two-thirds, rounded to apex, lateral marginal and lateral submarginal striae merging behind anterior corner, narrowly detached from median part of anterior marginal stria; pronotal disk narrowly depressed along anterolateral margin, ground punctation extremely fine, very sparse, with small secondary punctures only in lateral fourths; elytra with inner epipleural stria complete, outer epipleural stria present in basal half, outer and inner subhumeral striae absent, dorsal stria 1 present in basal half, stria 2 nearly complete, 3rd stria present in basal two-thirds, 4th stria slightly shorter, arched to meet base of sutural stria, 5th stria absent, sutural stria obsolete in apical fourth, elytral disk with small, shallow secondary punctures in apical third, mediad stria 3; prosternal keel narrow, flat, emarginate at base, carinal striae convergent at middle, diverging slightly, fragmented toward front; prosternal lobe about two-thirds keel length, apical margin rounded, marginal stria obsolete at sides; mesoventrite produced at middle, marginal stria complete; mesometaventral stria arched forward at middle, crenulate, detached from base of inner lateral metaventral stria, which extends obliquely posterad toward inner third of metacoxa, outer lateral metaventral stria very short, present as postmesocoxal fragment; metaventral disk impunctate at middle; abdominal ventrite 1 with complete inner lateral stria, outer lateral stria in apical half, disk impunctate at middle, ventrites 2-5 very finely, sparsely punctate across middle; protibia narrow, with four marginal denticles, the middle pair distant, margin serrulate between; mesofemur with posterior marginal stria weakly curving anterad along apical margin; mesotibia with two distinct marginal spines; outer metatibial margin smooth; propygidium lacking basal stria, with dense, ocellate secondary punctures separated by less than their diameters, propygidial gland openings inconspicuous; pygidium with fine ground punctation, small secondary punctures sparsely scattered, slightly smaller and sparser at middle of disk. Male genitalia (Figs 33 G–K): very similar to that of Baconia angustus , but dorsal lobes of T9 more distinctly triangular, ventrolateral tooth better developed; S9 quite different in overall shape, with base subangulate, with only very fine and weakly developed apical processes; aedeagus slightly longer, relatively narrower, basal piece less than one-half tegmen length.

Remarks.

This species is very closely related to Baconia angusta , but is relatively easily separated by distinctive features of the male genitalia. Externally, the overall body shape is more elongate (Fig. 32C) and slightly less depressed, its frons is more distinctly convex, the submarginal impression of the pronotum is weaker, and the secondary punctures of both pronotal sides and elytral apices are finer and shallower. The aedeagus of Baconia incognita is not quite as short, and the basal piece is proportionally shorter. The spiculum gastrale has very thin apical processes, but nothing like the prominent processes of Baconia angusta .

Etymology.

This species’ name refers to the fact that it was only discovered to be distinct very late in the process of assembling this manuscript.