Brasilaccoderus, Pollock, Darren A., 2006

Pollock, Darren A., 2006, Brasilaccoderus, a new genus of Eurypinae (Coleoptera: Mycteridae) from Brazil, Zootaxa 1368, pp. 41-48 : 42-44

Brasilaccoderus n. gen.

( Figs. 1–8 )

Laccoderus Champion 1916a: 106 (in part)— Champion 1916b: 225; Blackwelder 1945: 493; Elgueta & Arriagada 1989: 36.

Type species— Laccoderus scaber Champion , by present designation.

Diagnosis— Brasilaccoderus has the following diagnostic features among described world genera of Eurypinae : short antennae with submoniliform, serrated antennomeres; apical maxillary palpomere only slightly securiform; eyes relatively widely separated, with elongate interfacetal setae; male sexual patch on ventrite 2; elytra without dorsally visible apical patch.

Description— Body elongate, slightly ovate and depressed; body 3.2–3.7 times longer than greatest width; TL 5.2–9.9 mm. Head ( Figs. 3–4 ) relatively short, not or only very slightly narrowed behind eyes; frontoclypeal suture indicated laterally and medially by arcuate depression (especially distinct in B. scaber ); frons variously depressed medially, lateral margins elevated; anterior margin of clypeus with unsclerotized strip of cuticle; labrum transverse, outer surface distinctly convex; antennal insertions not concealed dorsally; antennae ( Fig. 5 ) short, extended posteriorly only to posterior margin of pronotum; scape elongate, widened distally; antennomeres 2–10 short, submoniliform and serrated; distal sensilla present from antennomere 3, especially dense on distal antennomeres; antennomere 11 elongate, constricted distal of midlength; eyes large, hemispherical ( Figs. 3–4 ), relatively widely separated; facets moderately fine, with elongate, erect intrafacetal setae; eyes only slightly more convex in males than females. Mandibles short, stout, symmetrical; apices blunt, bidentate; terebral teeth absent; inner margin incised abruptly, anterior of mola, deeper ventrally; mola relatively large, similar on both mandibles, surface with transverse shearing surfaces, without apparent microstructure; ventral groove/microtrichia absent; prostheca long, digitiform, extended distally from near anterior edge of mola. Maxilla with elongate palpi, apical palpomere slightly securiform; lacinia very slender, blunt distally, with dense brush of setae; galea broad, with apex produced inwardly, in contact with apex of lacinia; galea also with dense apical setal brush, especially on produced lobe. Labium with mentum transverse; ligula broad, subquadrate, extended significantly anterad base of palps; labial palpi short, distal palpomere blunt apically; gula relatively short, sutures convergent anteriorly, surface indistinctly convex. Prothorax with pronotum subquadrate, slightly wider than long (GPW/PL 1.1–1.3); lateral margins subparallel ( B. scaber — Fig. 1 ) or convergent anteriorly ( B. plaumanni — Fig. 2 ), without lateral carina; disc with medial depressions, variously developed (most distinct in B. scaber ); posterior pits present, openings incised, foveate, joined transversely by narrow arcuate groove; punctation more or less uniform, punctures shallowly ( B. plaumanni ) or deeply ( B. scaber ) umbilicate; setae adpressed and erect, the former directed in various directions; prosternal process short, knifelike, extended half the length of procoxae; internal portion of process indistinct; coxal cavities open externally and internally; protrochantin hidden; Mesothorax with mesoventrite triangular, lateral margins straight; mesepisterna very narrowly separated anteriorly, with distinct elliptical setose excavations anterolaterally; mesocoxal cavities partly closed by mesepimeron, with hidden trochantins; mesosternal process elongate, slender, touching short metasternal process. Metasternum convex, with distinct median line posteriorly for greater than half its length. Metendosternite with wide stalk; laminae large, lobate laterally; dorsal margin of body distinctly arcuate from midline to bases of elongate lateral arms; insertion points of anterior tendons not seen on the one dissected specimen. Elytra elongate, 2.2–2.6 times longer than greatest combined width, moderately convex; epipleuron distinct, visible to at least ventrite 4; elytral disc relatively smooth, punctate, with some small impunctate areas (especially in B. scaber ); vestiture dimorphic: large primary elytral punctures with adpressed setae; smaller secondary punctures with erect setae; apical patch present, although invisible dorsally. Legs ( Figs. 7–8 ) slender, all similar in size and shape; femora broad, tibiae relatively straight and slender; tibial spurs short, similar in size and shape; tarsal formula 5-5- 4 in both sexes, penultimate tarsomere short dorsally but with large subquadrate lobe ventrally; tarsomeres 2 and (especially) 3 triangular; last tarsomere elongate, distally widened slightly; all tarsomeres (except lobe on penultimate, and last) with long setae; tarsal claws with short, distinct basal tooth. Abdomen with first three ventrites connate; male with sex patch on ventrite 2; patch circular, with dense setae on raised medial area of ventrite. Male genitalia ( Fig. 6 ). Median lobe oriented dorsal to tegmen; apicale and basale subequal in length along lateral margins; basale deeply emarginate basally; parameres stout, curved inwardly at apices, with sparse apical setae; median lobe significantly longer than tegmen, without wide basolateral flanges, sides parallel basally, gradually narrowed to blunt apex; median lobe mostly membranous dorsally, with short sclerite along inner ventral surface; endophallus absent. Female genitalia (based on B. plaumanni , only). Ovipositor elongate, flexible, mostly unsclerotized; coxites 4-segmented, with very sparse, mostly short setae; last coxite very short, distinctly sclerotized; styli short, widened distally, with several long setae; valviferal and coxital baculi distinct; spiculum gastrale distinct, relatively wide; bursa copulatrix large, widened distally, external surface covered with longitudinal spiculae; side of bursa with short accessory branch; distinct spermatheca absent from single dissection performed.

Derivation of generic name— This name is a combination of the geographic placename Brasil, and Laccoderus , in which genus Champion originally placed B. scaber .

Geographical distribution— The examined specimens of Brasilaccoderus are are all from southeastern Brazil (São Paulo, Paraná, and Santa Catarina states).

Figures

FIGURE 1 – 2. 1. Brasilaccoderus scaber, habitus, male. 2. Brasilaccoderus plaumanni, habitus, male holotype.

FIGURES 3 – 8. 3. Brasilaccoderus plaumanni, outline of head. Scale bar = 0.5 mm. 4. Brasilaccoderus scaber, outline of head. Scale bar = 0.5 mm. 5. Brasilaccoderus plaumanni, female antenna. Scale bar = 0.5 mm. 6. Brasilaccoderus scaber, male genitalia, ventral. Scale bar = 0.25 mm. 7. Brasilaccoderus plaumanni, female protarsus, lateral. Scale bar = 0.25 mm. 8. Brasilaccoderus plaumanni, female metatarsus, lateral. Scale bar = 0.25 mm.