Laemophloeus souzalimai, Bento, 2021

Bento, Matheus, 2021, Laemophloeus souzalimai, a new species of lined flat bark beetle (Coleoptera Cucujoidea, Laemophloeidae) from Southeast Brazil, Zootaxa 5072 (3), pp. 278-284 : 279-282

Laemophloeus souzalimai , sp. nov.

( Coleoptera: Cucujoidea : Laemophloeidae )

Type material. Holotype male deposited at INPA, labeled: “ BRASIL: Bauru, SP / Lauro de Souza Lima / Arm. Luiz de Queiroz / I.2020 / Matheus Bento leg.” (white, printed with date handwritten) // “ Laemophloeus / sp. nov. / Bento 2021” (white, handwritten) // “ HOLOTYPE / Laemophloeus souzalimai / M. Bento, det. 2021” . Paratypes. Same data as holotype (2 ♂, 1♀, INPA) ; idem, but “ XII.2020 ” (1 ♂, INPA) ; idem, “but 26.XI–02.XII.2019 ” (1 ♂, 1 ♀, INPA) .

Diagnosis. Dorsal color testaceous, with elytra not maculate ( Fig. 1A, C ). Head with sides strongly excavated anteriad of eyes, forming laterally protruding, somewhat pedunculated eyes ( Fig. 2A–B ). Frons with a broad, Vshaped, deeply impressed line ( Fig. 2A–B ). Antennal emarginations of clypeus moderately deep and somewhat V-shaped ( Fig. 2A–B ). Antennal club composed of six antennomeres.

Description of holotype male ( Figs. 1A–B ; 2A–C ). Length 2.9 mm, width at mid-elytra 1.2 mm. Body elongate, parallel sided. Coloration. General color uniformly testaceous; head, pronotum, and legs slightly reddish brown; clypeal and mandibular apexes blackish. Head ( Fig. 2A–B ) large, more than twice wider than long, as long as and distinctly wider than pronotum; surface moderately punctate, with punctures much smaller than eye facets, each bearing a minute seta; lateral sides strongly excavated anteriad of eyes, forming laterally protruding, somewhat pedunculated eyes. Frontoclypeal suture completely effaced. Frons quite broad, with interocular width 8.3 times wider than transverse eye diameter; anterior region with a broad, V-shaped, deeply impressed line; longitudinal line effaced. Clypeus moderately emarginate, with mandibular emarginations broad, well defined; antennal emarginations moderately deep, somewhat V-shaped. Labrum large, as wide as median emargination of clypeus, subtrapezoidal, with anterior margin slightly emarginate; surface moderately setose, with setae as long as labrum length. Mandibles robust, moderately large, 0.6 times as long as head, conjunctly subtrapezoidal in closed position. Genal processes anteriorly projected, with acute apex. Antennae long, distinctly longer than half the body length; scape oblong-elongate, about 2.3 times longer than wide and shorter than antennomeres 2–3 combined, with basolateral obtuse denticle; pedicel globose, about 0.4 times length of scape; flagellum gradually widened toward apex, with antennomeres slightly elongate and narrower basally, and club 6-segmented comprised of antennomeres 6–11; antennomeres 4–5 subequal in length and slightly shorter than 3; 6–10 subequal in length; 11 large, slightly longer than scape, with a broad sensillar field; olfactory sensillae of club segments simple, not branched ( Fig. 2C, F ). Pronotum ( Fig. 2A–B ) subtrapezoidal, 1.9 times wider than long and anteriorly 1.4 times wider than posteriorly; surface moderately punctate, not microreticulate; punctures similar to head in size. Lateral margins evenly curved anteriorly, with a strong, broad posterior notch forming a distinct antebasal denticle. Anterior angles not produced, narrowly rounded; posterior angles acute, produced; sublateral line wide and deeply impressed, with minute, transverse setae. Elytra ( Fig. 1A–B ) not maculate, 1.4 times longer than conjunctly wide. Inner stria of cell 1 (sutural stria) medially effaced; striae of cells 2–3 complete and well defined. Humeral carina well marked. Lateral side external to humeral carina strongly declivous and narrowly explanate, with surface moderately covered with minute pubescence. Epipleuron gradually narrowed and incomplete, medially as wide as lateral side of elytron. Legs ( Fig. 1B ) short, with tibiae distinctly shorter than femurs. Femurs quite robust; metafemur enlarged, with medial width greater than half the length. Pro-, meso-, and metatarsus as long as respective tibiae, with inner surface moderately setose. Tarsal formula 5-5-4. Genitalia of paratype males (n = 2) ( Fig. 2G–I ). Parameres narrowly triangular, fused at basal half, with apex acute; each paramere with three basal, marginal setae: two short, inner setae and one long, outer seta surpassing the apex of parameres. Internal sac with a conspicuous, X-shaped basal sclerite; apex with sparse, large spinose processes. Claspers with two transverse, subrectangular lobes; apical outer angles with a dense tuft of long setae; apical inner angles produced as a large, sickle-shaped process, with short inner setae.

Variation. Smaller male paratypes vary in length from 2.4–2.5 mm and have shorter mandibles than the holotype.

Female ( Figs. 1C–D ; 2D–F ). The female paratypes are similar to males but differ from them in the following respects: body size much smaller than males, with sides slightly more curved. Length 2.2 mm. Width 0.9 mm. Head ( Fig. 2D–E ) quite smaller than males, 2.9 times wider than long, shorter and narrower than pronotum, with lateral sides weakly excavated anteriad of eyes, without protruding eyes. Frontoclypeal suture medially effaced and laterally distinct, but barely defined. Frons quite narrow, with interocular width 4.8 times wider than transverse eye diameter; anterior region with a small, V-shaped impressed line barely defined to completely effaced. Clypeus weakly emarginate, with mandibular and antennal emarginations shallow, barely defined. Mandibles weak, smaller than males. Antennae shorter than males, distinctly shorter than half the body length, with antennomeres 4–11 moniliform, globose. Pronotum ( Fig. 2D–E ) 1.6 times wider than long and anteriorly 1.2 times wider than posteriorly. Elytra ( Fig. 1C–D ) more elongated than males, 1.5 times longer than conjunctly wide. Lateral side external to humeral carina more strongly declivous than males, vertically positioned. Epipleuron narrower than lateral side of elytron at middle. Legs ( Fig. 1D ). Femurs robust, proportionally smaller than males, with medial width smaller than half the length. Tarsal formula 5-5-5.

Etymology. This species is named after Dr. Lauro de Souza Lima (1903–1973), one of the greatest Brazilian Hansenologists, who introduced the treatment and cure of Hansen’s disease in Brazil and left a wonderful legacy as a humanitarian doctor. The name is an honorific noun in the genitive case.

Type-locality. Brazil. São Paulo: Bauru.

Remarks. This is a quite distinctive species in the genus Laemophloeus and shares with L. germaini Grouvelle a large male head, with laterally protruding eyes, genal processes anteriorly projected and short, frons with a broad, Vshaped impressed line, and larger males with strong, conjunctly subtrapezoidal mandibles. However, L. souzalimai sp. nov. have dorsal color uniformly light testaceous, without elytral maculae (dorsal color predominantly dark testaceous, usually with elytra maculate or infuscate in L. germaini ), head with longitudinal line completely effaced (longitudinal line well defined in L. germaini ), antennal club 6-segmented (antennal club 8-segmented in L. germaini ), male head strongly excavated anteriad of eyes, forming somewhat pedunculated eyes (head slightly excavated anteriad of eyes in L. germaini ), and male clypeus with antennal emarginations somewhat V-shaped (antennal emarginations evenly rounded in L. germaini ). According to Thomas (2013), the frontal V-shaped, deeply impressed line in L. germaini is present in both sexes. In L. souzalimai sp. nov., this character is found barely defined to completely absent in females ( Fig. 2D–E ).

Concerning the structure of the club antennomeres as defined by Thomas (2013), the club is composed of antennomeres provided with apical clusters of specialized sensilla, regardless of relative width or color of the antennomeres. The new species has the club antennomeres with apical sensillar fields restricted to lateral pockets as opposed to the sensillar fields of L. germaini and L. macrognathus Reitter formed by a “peri-articular gutter” sensu Crowson (1981) partial or complete, which in these species begins on antennomere 4, forming a club composed of 8 antennomeres. Herein, scanning electron microscopy revealed that males and females of Laemophloeus souzalimai sp. nov. have the antennal club composed of 6 antennomeres, since the antennomeres 4–5 bear no such specialized sensillar field ( Fig. 2C, F ).

Figures

FIGURE 1. Laemophloeus souzalimai sp. nov.: dorsal and ventral views of the (A–B) holotype male and the (B–C) paratype female. Scale: 0.5 mm.

FIGURE 2. Laemophloeus souzalimai sp. nov.: head and pronotum, and antennomeres 4–6 of the (A–C) holotype male and the (D–F) paratype female. Genitalia of the paratype male: (G) claspers and aedeagus, (H) median lobe and tegmen, showing the X-shaped, basal sclerite of the internal sac, and (I) claspers. Scales: A, D = 0.3 mm; B, E = 200 µm; C, F = 50 µm. SEM images by Maria Oneide Silva de Moraes.