Baconia tricolor, 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 : 211-214

Baconia tricolor sp. n. Figs 1B, F2 A–B60A–C61A–D, F–GMap 19

Type locality.

PANAMA: Colón: San Lorenzo Forest [9.28°N, 79.97°W].

Type material.

Holotype male: "PANAMA: Colón Pr., San Lorenzo Forest. 9°17'N, 79°58'W. F.I.T., 21m, 10 d.FL-I1-C21a. 18.x.2003 R.Didham, L.Fagan. IBISCA" / "Caterino/Tishechkin Exosternini Voucher EXO-00471" (FMNH). Paratypes (16): PANAMA:1: Colón: P. N. San Lorenzo, STRI Crane Site, 9°17'N, 79°58'W, 14 m, 12-23.ix.2004, FIT, M. Rapp, 5: 28 m, 14-26.vii.2004, FIT, M. Rapp, 1: 28 m, 18.x.2003, FIT, R. Didham & L. Fagan, 1: 28 m, 19-25.v.2004, FIT, R. Didham, 1: 14 m, 23. viii– 2.ix.2004, FIT, M. Rapp, 1: 14 m, 23.x.2003, FIT, R. Didham & L. Fagan, 1: 28 m, 23.x.2003, FIT, R. Didham & L. Fagan, 1: 21 m, 26. iii– 5.iv.2004, FIT, M. Gonzales, 1: 14 m, 29.x.2003, FIT, L. Fagan & R. Didham, 1: 7 m, 29.x.2003, FIT, L. Fagan & R. Didham, 1: 28 m, 3-13.viii.2004, FIT, M. Rapp, 1: 21 m, 3-13.x.2004, FIT, M. Rapp (AKTC, GBFM, MSCC).

Diagnostic description.

Length: 1.4-1.5mm, width: 1.0-1.1mm; body elongate, sides subparallel, weakly depressed, conspicuously punctate on most surfaces, most punctures bearing single short, fine seta (may be abraded on dorsal and ventral surfaces, more persistent on pygidia); elytra faintly metallic blue, head and pronotum metallic blue-green, apical margin of elytra, pygidia and venter rufescent; frons produced in front, elevated above and between antennal bases, weakly depressed dorsad, uniformly punctate, frontal and supraorbital striae absent; antennal scape short, strongly bent at base, club rounded, slightly elongate; epistoma convex, straight across distal margin; labrum about 3 × wider than long, apical margin deeply and distinctly emarginate; mandibles short, each with median tooth; apical maxillary palpomeres slightly widened; pronotum with sides subparallel to slightly narrowing in basal three-fourths, abruptly narrowed to apex, lateral marginal stria continuous around sides and front, lateral submarginal stria very close to marginal, subcarinate, merging near anterior corner; pronotal disk weakly depressed along inner edge of anterior half of lateral submarginal stria; punctation of pronotal disk coarse, more or less uniform; elytra with two complete epipleural striae, outer subhumeral stria absent, inner subhumeral stria usually represented by short basal fragment, dorsal striae 1-5 present to base, variably abbreviated in apical fourth, sutural stria present in apical two-thirds, may be abbreviated apically, elytral disk with sparse secondary punctures throughout, slightly denser in apical fourth; prosternal keel narrow, weakly convex, narrowly, shallowly emarginate at base, carinal striae convergent in basal half, united by arch just distad middle; prosternal lobe about half keel length, apically truncate, marginal stria obsolete at sides; mesoventrite narrowly produced at middle, marginal stria usually complete, may be narrowly interrupted medially; mesometaventral stria arched forward at middle, continuous with inner lateral metaventral stria from inner corner of mesocoxa to middle of metacoxa, short fragment of outer lateral metaventral stria present near base; mesometaventral and abdominal ventral disks very finely and sparsely punctate; abdominal ventrite 1 with complete inner lateral stria and median fragments of outer lateral stria; protibia with 3-4 marginal denticles, the basal-most usually weak, margin finely serrulate between; mesotibia with 2-3 marginal spines; outer metatibial margin smooth; propygidium lacking basal stria, propygidial gland openings evident about one-third distance from anterior and lateral margins; propygidium and pygidium with coarse punctation throughout. Male genitalia (Figs 61 A–D, F–G): T8 short, basal emargination deep, subacute, sides rounded, apical emargination narrowly acute, ventrolateral apodemes transversely convergent basally, barely projecting distad; S8 about as long as broad, halves approximate at inner bases only, rapidly narrowed apically, apical guides widening to apex, apical membrane lightly sclerotized to form bilateral velar disks which nearly meet along the midline; T9 with proximal apodemes narrow, about one-half total length, dorsal lobes evenly narrowed to apices, ventrolateral apodemes very prominent, acuminate, strongly recurved proximad; T10 entire; S9 parallel-sided, apices short, divergent, quadrate; tegmen parallel-sided in basal third, strongly narrowed to apex, thick in lateral aspect, weakly curving ventrad over much of length; median lobe nearly one-half tegmen length, with very short proximal apodemes; basal piece broad, about one-third tegmen length.

Remarks.

This species is fairly distinct in its coloration alone (Fig. 60A). However, there are a number of more or less similar (i.e., narrow and subcylindrical) species in this group and others. The best characters for separating it besides its coloration are the fine setae, preserved almost invariably on the pygidia if not elsewhere (Figs 60A, C), the convex frons, and the narrowly emarginate labrum (Fig. 60B).

Etymology.

The greenish pronotum, blue elytra, and rufescent pygidia of this species make for a distinctly tricolored dorsal appearance.