Stenocerus fratris, Lopes & Mermudes, 2018

Lopes, Marcela Paes De A. M. & Mermudes, José Ricardo M., 2018, Four new species and new synonymy in Stenocerus Schoenherr, 1826 (Coleoptera, Anthribidae, Anthribinae, Stenocerini), Zootaxa 4472 (3), pp. 471-488 : 475-478

Stenocerus fratris sp. nov.

( Figs. 15–28 )

Etymology: Latin, fratris = brother, allusive to the great resemblace with S. angulicollis Jekel, 1855 and S. varipes Fahraeus, 1839 .

Diagnosis: Rostrum slightly grooved longitudinally, lacking median carina; lateral carinae evident. Prothorax with antebasal carina rounded at middle third, oblique to apex; lateral carina elongate, semi-curve and slightly protruding before middle. Pronotum elevated at middle, with three circular areas arranged transversely, clothed by black-brownish scales. Elytra with checkered pattern on interstriae 1, alternated black spots at median third arranged obliquely on interstriae 3, 4, 5 and 7, almost forming a stripe; at apical third minor black spots on interstriae 3, 5 and discreetly on interstria 7. Mesosternal process feebly convex at anterior margin, convergent sides, posterior margin rounded.

Description: Male ( Figs. 17–28 ). Integument reddish-brown. Dorsal vestiture: rostrum with fine, short and decumbent light-brown scales intermingled yellowish and pale scales; frons, each side of ocular margin, with narrow yellow stripe, formed by short and decumbent scales; antennomeres III–XI ( Fig. 19 ) with fine, elongate, erect yellowish setae throughout each antennomeres; VIII and club (IX–XI) with dense light brownish pubescence; pronotum and elytra with moderate dense scales of variegated colours (yellowish, pale, and light to blackbrownish); pronotum with three circular areas clothed with black-brownish scales, arranged transversely at medial elevation, each side slightly anterior; scutellum with white, dense and short pilosity; elytra ( Fig. 23 ) with checkered pattern on interstriae 1 alternated; black spots at median third arranged obliquely on interstriae 3, 4, 5 and 7, almost forming stripe; at apical third minor black spots on interstriae 3, 5 and discreetly on interstria 7; pygidium with brownish scales. Ventral vestiture: black-brownish; sides of pro- and mesothorax and femora with minute yellowish spots; ventrites with yellowish and irregular spots at sides, near distal margin; tibiae with discrete annular yellow-pale stripe at median third; tarsomere I with dense pale-yellow scales; II brownish.

Head slightly microcorrugate. Rostrum ( Fig. 17 ) microcorrugate, 1.8x longer than wide at base, slightly grooved longitudinally; lacking median carina; lateral carinae evident; apical margin notched, angulate at middle. Sides of rostrum with distance between scrobe and eye ( Fig. 18 ) subequal to maximum lateral width of eye; ventrally with median carina, lacking fovea. Mentum glabrous, with apical margin subtruncate. Antennae exceeding middle third of pronotum; scape stout; antennomere II cylindrical and thickened, with apex wider than base, almost twice shorter than III; III–XI depressed dorsally, slightly expanded at apex; III the longest; IV slightly shorter than III; V–VIII weakly decrease in length; club with IX–XI subequal in length; XI apical margin acute.

Prothorax ( Figs. 20–21 ) about 1.5x wider than long. Pronotum ( Fig. 20 ) with discrete depression, but large, deeper parallel to central transverse elevation; carina antebasal, rounded at middle third; slightly convergent from antebasal carina forward anterior margin; lateral carina ( Fig. 21 ) elongate, semi-curved and slightly protuding before middle. Prosternum subglabrous and corrugate; prosternal process not exceeding distal margin of cavity I. Mesosternal process ( Fig. 22 ) feebly shorter than width of mesocavity, feebly concave at anterior margin; sides convergent and prominent and rounded posterior margin. Scutellum subsquare, with parallel sides, broadly rounded at apex. Elytra ( Fig. 23 ) short, about 1.3x longer than wide across humeri, with parallel sides, convergent at apical third; lacking tubercles.

Abdomen ( Fig. 24 ): ventrites I–IV feebly depressed at disc; ventrite V 1.2x longer than IV, apical margin weakly concave. Pygidium ( Fig. 25 ) with length of apical portion subequal to basal half; apical margin broadly rounded. Terminalia ( Figs. 26–27 ): tergite VIII ( Fig. 26 ) transverse, longer than wide, sides slightly convergent from base to apex, apical margin weakly rounded, little sclerotized near sides and apex, with moderately long setae; sternite VIII membranous, transverse, with lateroapical lobes not well-defined, pigmented, with moderately long setae; sternite IX with apodeme 6.5x longer than arms. Tegmen ( Fig. 27 ) with length of apodemes slightly shorter than sclerotized ring, with basal margins pigmented, rod 2.2x longer than arms; sclerotized-ring with pre-apical margin deeply sinuous and sclerotized; parameres fused, sides slightly convergent; apical margin truncate, with moderate dense and long setae; strongly sinuous (lateral view). Penis ( Fig. 28 ) few curve and elongate, body 1.5x the length of apodemes; bridge between apodemes weakly sclerotized at proximal margin; tectum membranous, slightly pigmented, about twice longer than wide, with sides weakly sclerotized, convergent to apex, this subrounded; pedon continuous with apodemes, these gradually sclerotized from base to apex; subtruncate at apex. Internal sac feebly shorter than apodemes, almost 2.3x shorter than penis, spiculate ventrally and dorsally at proximal area.

Type material: Holotype male from Brazil, Espirito Santo, Santa Maria de Jetibá , XI/ 1958, 800 m; Stenocerus fratris sp. nov.; Holotype male, Lopes & Mermudes det. 2017 ( DZUP)—dissected.

Remarks: Stenocerus fratris sp. nov. ( Figs. 15–16 ) has features of both S. varipes Fahraeus, 1839 and S. angulicollis Jekel, 1855 , but it differs by (differences in parentheses): 1) integument reddish-brown (either S. angulicollis and S. varipes are dark black-brownish); 2) rostrum narrow and elongate, lacking median carina, grooved longitudinally, but with evident lateral carina ( S. angulicollis has rostrum similar in length but it had elevated median carina; S. varipes , on the other hand, has rostrum feebly shorter and broader, lacking median carina); 3) prothorax with antebasal carina rounded at middle third ( S. varipes and S. angulicollis are broadly rounded); 4) elytral vestiture with distinct checkered pattern on interstriae 1, alternated black spots at median third arranged obliquely on iterstriae 3, 4, 5 and 7, almost forming a stripe; at apical third minor black spots on interstriae 3, 5 and discreetly on 7 (interstriae 1 similar in both species, but lacking black spots at median third); 5) mesosternal process ( Fig. 22 ) feebly shorter than width mesocavity, feebly convex at anterior margin; prominent and rounded posterior margin ( S. varipes and S. angulicollis have mesosternal process as wide as width mesocavity, broadly convex at anterior margin and posterior margin, which evidently not prominent).

Figures

FIGURES 15–16. Stenocerus fratris sp. nov., holotype male from Santa Maria de Jetibá (Espírito Santo): 15, dorsal; 16, lateral.

FIGURES 17–28. Stenocerus fratris sp. nov., holotype male: 17, head, dorsal view; 18, head, lateral view; 19, antenna; 20, pronotum; 21, prothorax, lateral; 22, mesosternal process; 23, elytra, dorsal; 24, abdomen, ventral; 25, pygidium, dorsal; 26, tergite and sternite VIII, ventral; 27, tegmen, dorsal and lateral; 28, penis, dorsal and lateral.