Corotoca fontesi, Zilberman, 2018

Zilberman, Bruno, 2018, New species and synonymy in the genus Corotoca Schiødte, 1853 (Coleoptera, Aleocharinae, Corotocini), Zootaxa 4434 (3), pp. 547-560 : 548-551

Corotoca fontesi sp. nov.

Female: Length 2.7mm–3.2mm ( Figs. 1, 2 )

Male: Length 2.4–2.6 mm ( Figs. 3, 4 )

Body partially membranous with abdomen bent upwards and strongly physiogastric. Membranous area milkywhite. Chitinous portion of head light brown; antennal scape yellowish-brown, with remaining antennomeres lighter; pronotum brown, dark brown on lateral portions, darker on anterior edges, anterior margin and medial region lighter; legs light to dark brown; elytra pale. All antennomeres pubescent; abdominal sternites covered with short to long bristles.

Head. Transverse, widest behind eyes, gula subtriangular, widest at base, fused to mentum; foramen magnum occupying ¾ of head width ( Fig. 5 ); vertex with four long bristles in a transversal row ( Fig. 37 ). Clypeus membranous and pubescent. Antennae with 11 antennomeres; scape elongate and convex at outer border; antennomere II subquadrate; antennomeres III–X decreasing gradually in size ( Fig. 6 ); antennomeres III, X, each with one sensillum at apical region ( Figs. 7, 8 ); last antennomere longer than IX, X or VIII and the same length of VII, with a pair of sensilla at medial region ( Fig. 9 ). Mouthparts. Labrum membranous, transverse, about 0.4 time larger than long, with anterior margin almost continuous ( Fig. 10 ); five long bristles on each side, distributed in two pairs in a diagonal row (D2–D1/ M2–M1) and one more basal (P2); numerous short setae covering anterior margin ( Fig. 48 ). Mandibles. Symmetrical, narrow; internal margin with a subapical mesal, short and stout tooth ( Fig. 11 ); outer margin with one to three short bristles. Maxilla with cardo semitriangular; stipe broad, 1/3 wider than long, with a long bristle at base, close to cardo; lacinia subquadrate, with two short bristles at base, close to stipe, and a row of stout bristles on internal margin; galea narrow, the same lenght of lacinia; surface densely covered with small bristles; maxillary palpi densely setose and with four palpomeres: palpomere I short, II subcylindrical, III suboval and IV reduced; three first palpomeres covered with long bristles and last by short bristles ( Fig. 12 ).

Labium. Prementum subquadrate almost as wide as long, with labial palpi setose, 3-articulated; palpomeres I and II subquadrate; last elongate and narrow ( Fig. 13 ); mentum fused to submentum, with six marginal long bristles and two to four internal ones; marginal bristles distributed as follows: apical (ap), preapical (pa) and proximal (px) ( Figs. 14 , 44 ).

Thorax. Prothorax. Pronotum two times larger than long; anterior margin emarginated and lateral angles broadly rounded; discal area trituberculate: with a median tubercle very developed with one smaller, on each side; microsculptured small areas in semi-losange shaped units, covering all surface; a long bristle on each lateral region is present ( Figs. 37 , 38 ). Mesothorax. Mesonotum slightly longer than metanotum, with two medial bristles symmetrically distributed, surrounded by some short bristles irregularly arranged ( Figs. 15, 16, 17 ). Mesosternum without carena and fused to metasternum, with two long bristles each one, located behind posterior coxal cavities; bristles in medial region, if present, very small and scarcely distributed ( Fig. 18 ). Metathorax. Metanotum: endosternite with a long medial articulating process, separating posterior legs ( Figs. 15, 19 ); space between legs more than a half of width of posterior margin of metasternum; a dark spot losange-shaped in medial-basal region ( Fig. 36 ); in male, only contour is visible, with median area very lighter; a longitudinal row of bristles of varied sizes on medial region, reaching base of endosternite. Legs. Well-developed; anterior coxae elongate, median and posterior coxae suboval; femur almost same size of tibia; posterior tibia elongate, with base abruptly declivous and with a row of long bristles on internal margin ( Figs. 21, 22, 23 ). Scutellum semi-fusiform, 1.5 times larger than long ( Fig. 15 ). Elytra covering meso and metathorax, wider on anterior region, narrowed apical on sutural margin; sutural margins separate, not fitted ( Fig. 24 ); all surface covered with very short bristles. Hind wings vestigial, with a long lateral sclerite and indistinct nervure ( Fig. 25 ).

Abdomen largely membranous, bent at segment III level; sclerites composed only by tergites and sternites, without paratergites; tergite I represented by a narrow sclerotized and reduced sclerite attached to metanotum, with medial region slightly projected backwards ( Fig. 16 ); segment II represented by a transverse tergite with lateral margins narrow and medial depression broad and shallow ( Figs. 26 , 46 ); segments III–X composed each by tergite and sternite complete, except in female which sternite IX is absent; tergites IV and V with very long lateral extensions, fused along their length, almost encircling the abdomen ( Figs. 1 , 26, 27 ); tergite VII subquadrate and about 3 times longer than tergite VI ( Fig. 28 ); sternites V–VI subquadrate, not reaching lateral margins of abdomen ( Fig. 2 ); in lateral view abdomen appearing transverse in form, rather than semicircular ( Fig. 1 ); sternite VII truncate, with relatively short bristles densely distributed; tergite VIII slightly subquadrate, about as wide as long (not considering lateral extensions), with pronounced lateral extensions; four primary long bristles distributed in pairs on each side ( Figs. 29 ); sternite VIII about three times wider than long, covered by short bristles, more dense on anterior margin, with six long bristles distributed symmetrically on anterior margin, three on each side of tergite; sometimes one to four bristles in a transversal row in medial region ( Fig. 30 ); sternite IX on male mostly membranous, sub-triangular; four bristles asymmetrically distributed anteriorly as shown in Figs. 31, 32 ; tergite IX semitriangular and bilobed, each lobe with three bristles, sometimes one side with four; tergite X not continuous, divided in two elongate portions, each one with three bristles, sometimes one side with four ( Fig. 33 ). Aedeagus with lateral lobes curved towards median lobe, not reaching median lobe apices, giving the appearance to be shorter in resting position ( Fig. 34 ). Spermatheca elongate, with capsule reduced, much shorter than width of stem; stem sinuous in pattern ( Fig. 35 ).

Etymology. The specific epithet is patronymic, in honor of Dr. Luiz Roberto de Oliveira Fontes, termitologist who at the beginning of his career worked on termitophile beetles at MZUSP.

Type material. Holotype, female: BRAZIL: Brasília ( Road Brasília-Cristalina , km 98), 30.IV.1978, Seixas, C. T. & Kato, T. cols., in alcohol ( MZUSP 21238 ) . PARATYPES (1 male, 1 female): BRAZIL: Ceará, Crato , 10.XI.1975, Araujo, R. L. col., in alcohol ( MZUSP 21239 ) .

Figures

FIGURE 36. Corotoca fontesi sp. nov., male (left) and female (right), ventral view. Scale bar = 0.5 mm.

FIGURE 37. Corotoca fontesi sp. nov., pronotum and vertex, dorsal view.

FIGURE 38. Corotoca fontesi sp. nov., bristles on pronotum and vertice, lateral view.

FIGURES 1–2. Corotoca fontesi sp. nov., holotype female. 1, lateral habitus; 2, dorsal habitus. Scale bars = 0.5 mm.

FIGURES 3–4. Corotoca fontesi sp. nov., paratype male. 3, lateral habitus; 4, dorsal habitus. Scale bars = 0.2 mm.

FIGURES 5–14. Corotoca fontesi sp. nov., 5, head ventral view; 6, antenna; 7–9 antennomeres showing the sensilla; 7, third antennomere; 8, tenth, antennomere; 9, last antennomere; 10, labrum; 11, left and right mandibles; 12, maxilla; 13, prementum; 14, mentum; Scale bars = 0.1 mm, except fig. 6= 0.5 mm; figs 10, 14= 0.05 mm.

FIGURES 48–49. Chaetotaxy of labrum. 48 Corotoca fontesi sp. nov.; 49, Corotoca phylo Schiødte, 1853. Scale bars = 0.05 mm.

FIGURES 44–45. Chaetotaxy of mentum. 44, Corotoca fontesi sp. nov.; 45, Corotoca phylo Schiødte, 1853. Scale bars = 0.05 mm.

FIGURES 15–35. Corotoca fontesi sp. nov., 15, scutellum, meso- and metathorax; 16, meso- and metanotum, and abdominal tergite I; 17, bristles indicated by arrow on mesonotum; 18, bristles indicated by arrow on mesosternum; 19, endosternite; 20, bristles on metasternum; 21, anterior leg; 22, median leg; 23, posterior leg; 24, elytra; 25, vestigial wing indicated by arrow; 26, tergites II–IV; 27, tergite V (lateral extensions broken); 28, tergites VI–VII; 29, tergite VIII; 30, sternite VIII; 31, sternite IX; 32, bristles on sternite; IX. 33, tergite IX–X (one side of tergite IX broken); 34, aedeagus, dorsal; 35, spermatheca. Scale bars = 0.1 mm except figs 15, 16, 21–23=0.5 mm; figs 27–28, 32, 35= 0.05 mm.

FIGURES 46–47. Tergite II. 46, Corotoca fontesi sp. nov.; 47, Corotoca phylo Schiødte, 1853. Scale bar fig. 46= 0.2 mm; fig. 47= 0,5 mm.