Baconia azuripennis, 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 : 218-220

Baconia azuripennis sp. n. Figs 62 E–F63D–F, H, K–LMap 19

Type locality.

ECUADOR: Orellana:Res. Ethnica Waorani [0.67°N, 76.43°W].

Type material.

Holotype male: "ECUADOR: Orellana: Res. Ethnica Waorani, 1 km S Onkone Gare Camp, Trans. Ent., 0°39'10"S, 76°26'W, 220 m, 12 Febr 1995, T.L.Erwin et al., collectors" / "fogging, bare green leaves, some with covering of lichenous or bryophytic plants in terra firme forest. Project MAXUS Lot 1041 Trans. 5 Sta. 2" / "Caterino/Tishechkin Exosternini Voucher EXO-00409" (USNM). Paratypes (5): FRENCH GUIANA: 1:Montagne des Chevaux, 4°43'N, 52°24'W, 11.vii.2009, FIT, SEAG (CHND), 1:27.vi.2009, FIT, SEAG (MNHN), 1: 3.iv.2011, FIT, SEAG (MNHN); Savanne Matiti 4.0833°N, 52.6167°W, FIT, SEAG (FMNH); 1: Belvèdére de Saül, 3°1'22"N, 53°12'34"W, 31.xi.2010, FIT, SEAG (MSCC).

Diagnostic description.

Length: 2.5-2.7mm, width: 2.2-2.5mm; body broadly oval, moderately depressed, glabrous; elytra metallic blue, rest of body piceous, shining; frons broad, interocular margins convergent dorsad, frontal disk transversely, arcuately elevated above and between antennal bases, frontal stria absent along margin of eyes but complete across front, finely carinate, frontal disk bilaterally depressed behind, moreso in male, ground punctation conspicuous, rather dense; supraorbital stria absent; antennal scape short, thick, club slightly asymmetrically oblong; epistoma strongly recessed below frontal ridge, straight across apex; labrum about 2 ×wider than long, apical margin outwardly arcuate; mandibles narrow, convex, left mandible with small basal tooth, right mandible edentate; pronotum wide, sides evenly arcuate from base to apices, lateral marginal and submarginal striae close, parallel, separate to anterior corner, marginal stria usually rounding corner, ending free, submarginal stria usually detached from anterior marginal stria, disk largely impunctate at middle, with very small, sparse punctures becoming evident in lateral thirds; elytra with three epipleural striae, outer subhumeral stria present in basal two-thirds, inner subhumeral stria complete, dorsal striae 1-4 complete, 5th stria generally present in apical half, may be absent, sutural stria present in apical half to two-thirds, elytral disk punctate along apical margin; prosternal keel moderately broad, weakly convex, truncate or very shallowly emarginate at base, carinal striae subparallel, separate throughout, usually obso lete in apical fifth; prosternal lobe about one-half keel length, apical margin rounded, marginal stria present only at middle; mesoventrite straight to weakly produced at middle, marginal stria interrupted for nearly width of prosternal keel; mesometaventral stria broadly arched forward, detached laterally from inner lateral metaventral stria, which curves obliquely posterad toward middle of metacoxa, outer lateral metaventral stria very short; metaventral and abdominal disks impunctate at middle; abdominal ventrite 1 with single complete lateral stria; protibia tridentate, outer margin serrulate; mesotibia with two small marginal spines; outer metatibial margin with fine subbasal denticle; propygidium lacking basal stria, that of female simply biimpressed, with uniformly scattered secondary punctures, that of male deeply impressed on either side of distinct median keel, entire middle of propygidium alutaceous, setose; pygidium of female with moderately dense small punctures, that of male densely alutaceous. Male genitalia (Figs 63 D–F, H, K–L): T8 slightly longer than wide, basal emargination very shallow, basal rim slightly explanate, sides subparallel, apical emargination subacute, ventrolateral apodemes well sclerotized, separated by two-thirds T8 width, projecting distad about one-third from base; S8 longer than broad, halves approximate at inner bases, narrowing apically, apical guides very weakly developed at sides, apices narrowly rounded, moderately well-sclerotized; T9 broad, proximal apodemes very short, apices divergent, bluntly rounded, bearing a single conspicuous seta, ventrolateral apodemes bluntly rounded beneath; T10 cordate; S9 short, broadly subtruncate at base, narrowed to near apex, apical arms thin, divergent, apical emargination deeply subacute; tegmen sides weakly sinuate, narrowed near middle, in lateral view revealing a distinct ventral longitudinal keel; median lobe about one-half tegmen length; basal piece short, about one-fifth tegmen length.

Remarks.

While the similarities of this species to Baconia riouka are obvious, and a close relationship is supported by numerous characters, external and genitalic, males are easily separated by the extreme sexual dimorphism of the propygidium, and both sexes are distinct in the metallic blue coloration of the elytra of Baconia azuripennis (Fig. 62D). As above, the male modifications appear to be elaborations associated with the propygidial glands, which in the male are not otherwise visible, while being simple and apparent in the female.

Etymology.

This species is named for the strongly metallic blue elytra.