Baconia bullifrons, 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 : 115-117

Baconia bullifrons sp. n. Figs 32 G–H34A–HMap 9

Type locality.

GUYANA: Region 8: Iwokrama Forest [4.28°N, 58.51°W].

Type material. Holotype male: "GUYANA: Region 8, Iwokrama Forest, Kabocalli Field Stn., 60 m 4°17'4"N, 58°30'35"W, 3-5 JUN 2001; R.Brooks,Z.Falin, GUY1BF01 146, ex: flight intercept trap" / “SM0567606” (SEMC). Paratypes (7): FRENCH GUIANA: 1: Rés. des Nouragues, Camp Inselberg, 4°05'N, 52°41'W, 25.i.2011, FIT, SEAG; 1: Rés. des Nouragues, Saut-Parare, 4°02'16.1"N, 52°40'21.1"W, 20.x.2009, FIT, S. Brule; 3: Belvèdére de Saül, 3°1'22"N, 53°12'34"W, 7.ii.2011, FIT, SEAG; 1:Montagne des Chevaux, 4°43'N, 52°24'W, 1.viii.2009, FIT, SEAG (CHND). 1: SURINAME: Sipaliwini: CI-RAP Survey camp 1, upper Palumeu, 225m. 2.47700°N, 55.62941°W, FIT, 10-16.iii.2012, A.E.Z. Short. SR12-0310-TN1 (SEMC).

Other material.

(5): BRAZIL: 1: Manaus: INPA, 2°25'S, 59°50'W, i.1994, Winklered leaf litter, terra firme forest, R. Didham; 2: Pará: Monte Alegre, 3°09'S, 52°03'W, 17.vi-3.vii.1992, FIT; Santa Catarina: Nova Teutonia, ii.77, F. Plaumann (MHNG); 1: Paraná: Piraquara, Mananciais de Serra, 25°29.77'S, 48°58.90'W, 1000 m, 17-31.x.2007, FIT, P. Grossi & D.Parizotto (UFPR).

Diagnostic description.

Length: 1.0-1.2mm, width: 0.9-1.0mm; body elongate oval, moderately depressed, glabrous; color rufescent, shining; head with frons strongly elevated over antennal bases as oblique carinae, interrupted, depressed at middle, interocular margins convergent dorsad, frontal punctation very fine and sparse, few punctures near vertex, frontal stria present along inner margins of eyes and along outer half of each oblique carina, supraorbital stria vaguely represented by few confluent punctures; antennal scape short, club short, rounded; epistoma weakly emarginate; labrum about 3 × wider than long, apical margin truncate to weakly produced; mandibles short, each with median tooth; pronotum with sides weakly convergent in basal two-thirds, abruptly narrowed to apex, marginal stria complete along lateral and anterior margins, lateral submarginal stria present in basal two-thirds, ending freely; pronotal disk not depressed in anterior corners, ground punctation extremely fine, small secondary punctures present only in middle of lateral fourths; elytra with single complete epipleural stria, outer and inner subhumeral striae absent, dorsal stria 1 present in slightly less than basal half, stria 2 nearly complete, 3rd stria present in basal half or slightly more, 4th stria shorter, present in basal third and arched to meet base of sutural stria, 5th stria absent, sutural stria obsolete in apical fifth, elytral disk with small, shallow secondary punctures in apical half, mediad stria 4, extending further laterad at apex; prosternal keel moderately broad, weakly convex, emarginate at base, carinal striae slightly convergent at middle, divergent anterad and posterad; prosternal lobe about one-half keel length, apical margin rounded, marginal stria complete; mesoventrite produced at middle, marginal stria complete or narrowly interrupted at middle; mesometaventral stria angulate forward at middle, fine, smooth, meeting inner lateral metaventral stria at mesocoxa, continuing obliquely posterad, curving toward outer corner of metacoxa, abbreviated apically, outer lateral metaventral stria short, present as postmesocoxal fragment; metaventral disk impunctate at middle; abdominal ventrite 1 with single, complete lateral stria, disk impunctate at middle, ventrites 2-5 finely, sparsely punctate across middle; protibia narrow, with three or four marginal denticles, margin ser rulate between; mesofemur with posterior marginal stria not extending onto apical margin; mesotibia with two distinct marginal spines; outer metatibial margin smooth; propygidium lacking basal stria, with fine, sparse ground punctation and rather small secondary punctures separated by 1 –1.5× their diameters, propygidial gland openings inconspicuous; pygidium with fine ground punctation, small secondary punctures present only along basal margin. Male genitalia (Figs 34 A–H): T8 subquadrate, about as long as broad, sides subparallel, basal emargination shallow, basal rim well-sclerotized, apex very shallowly, narrowly emarginate, ventrolateral apodemes extending nearly to longitudinal midline, inner apices separated by about one-half T8 width; S8 divided, about as long as T8, inner margins approximate at base, divergent apically, outer margins weakly divergent, apical guides present, widened to near apex, narrowly rounded apically, apical velar membrane absent, apex with few inconspicuous setae; T9 with basal apodemes elongate, sinuous, nearly one-half total length, dorsal lobe of T9 elongate subtriangular, ventrolateral apodemes bluntly pointed at inner apices; S9 varied, may be completely divided, stem absent, with thin or absent basal bridge between the halves, apices divergent, with deep crease along lateral margin dividing distinct dorsal and ventral lobes; tegmen widest near base, evenly narrowed to apex, in lateral aspect rather thick throughout, abruptly bent ventrad in apical fourth; median lobe simple, about one-third tegmen length; basal piece about one-third tegmen length.

Remarks.

This is the most externally recognizable species in the Baconia angusta group. The oblique frontal carinae are unique (Fig. 32H), as are the slightly rounded body form (Fig. 32G) and the submarginal pronotal stria distinctly removed from the margin. The male genitalia of this species are perhaps relatively plesiomorphic in some respects, in having relatively well-developed apical guides on the 9th tergite. The spiculum gastrale is nearly or fully divided, and has a distinctive apicolateral crease. We have limited the type series to specimens from the Guianas due in part to this genitalic variation.

Etymology.

This species is named for its distinctive frontal swellings.