Elytroleptus quadricostatus Grzymala & Miller, 2013

GRZYMALA, TRACI L. & MILLER, KELLY B., 2013, Taxonomic Revision and Phylogenetic Analysis of the Genus Elytroleptus Dugés (Coleoptera: Cerambycidae: Cerambycinae: Trachyderini), Zootaxa 3659 (1), pp. 1-62 : 39-40

Elytroleptus quadricostatus Grzymala & Miller , sp. nov.

(Figs. 15, 37)

Type material. Holotype. (here designated, Fig. 15), Elytroleptus quadricostatus ( FSCA, ♀) labeled: Label 1: ‘ Mexico / Cuautla / VI-4-1922 / E.G. Smyth coll.’

Paratype. (here designated), Elytroleptus quadricostatus ( FSCA, ♀) labeled: Label 1: ‘Guat. Zacapa / 2 km S San Lorenzo /5400’, Jun 3-5, 1989 / E. Giesbert, Coll .’

Type locality. Mexico, Morelos, Cuautla.

Etymology. This species is named for the four costae present on each elytron. Some congeners exhibit the four costae state, but they are not as apparent as in this species.

Diagnosis. This species is distinguished from all other species of Elytroleptus by the following combination of characters: 1) elytra laterally expanded apically, greatest width>1.5 × width at humeral angle, 2) each elytron with four costae, 3) pronotal integument black with two longitudinal lines of dense, appressed testaceous pubescence overlying testaceous integument, 4) elytra with moderate punctation, 5–6 punctures between suture and costa I medially, and 5) basal elytral integument testaceous. This species most closely resembles E. grandis and can be distinguished by the shorter antennae and larger deeper punctures on the elytra, 5–6 punctures medially between suture and costa I. From E. nigripennis it is distinguished by the testaceous basal elytral integument and the central pronotal disc thinly covered with black pubescence.

Description. Female. TL 13.1–15.8 mm, GW 5.1–6.1 mm. Body elongate, laterally expanded apically from humeri, dorsoventrally flattened.

Head. HL 0.9–1.0 mm, HW 1.7–3.1 mm, DBA 0.7–0.8 mm, DLE 1.0– 1.1 mm. Piceous, except vertex, anteclypeus, and, labrum testaceous. Moderately punctate with long, erect, sparse testaceous pubescence, shorter, generally rounded, width greater than ½ × height. Eyes moderately large, finely faceted, lower lobe with 30 facets at greatest height; integument ventral to lower lobe about 0.2 × eye height; deeply emarginate at antennal insertion, with 3 facets at greatest point of emargination. Antennae black, extending to about ¼ elytral length, scape and antennomere V subequal; pedicel about 1/3 × scape length; antennomeres III and IV subequal, each about 2.2 × pedicel length; antennomeres V–VIII decreasing in length; antennomeres VIII and IX subequal; antennomere X slightly shorter than IX; antennomere XI about 1.6 × length of X, slightly appendiculate.

Thorax. PL 1.8–2.1 mm, PW 2.3–2.5 mm. Pronotum piceous, slightly wider than long, apical constriction subequal to basal constriction, lateral margins slightly angulate, widest medially. Central pronotal disc shining, punctate, with short, recumbent, black pubescence arising from punctation; laterad to center, two (one on each side) distinct longitudinal, arcuate lines of dense, appressed, testaceous pubescence overlying slightly raised, testaceous integument, each of similar width throughout and occupying ¼ of pronotal disc area; punctation on shining areas deep, individual punctures small and varying in diameter and shape, majority not strongly delimited; pronotal disc flat to slightly convex, sides impressed in dorsal aspect, margin apparently elevated, calli absent; lateral margins lined with recumbent and erect, moderate, black pubescence. Pro-, meso-, and metasternum black, shining with sparse, long erect, testaceous setae. Scutellum black, small, subtriangular, length subequal to width, medially impressed, with short, moderately dense, recumbent black pubescence.

Wings. EL 10.4–12.7 mm. Elytron with basal 2/5 testaceous, apical 3/5 piceous with violaceous sheen, margin irregular. About 5.6 × PL, width at humeral angles about 1.3 × PW. Elytron laterally expanded apically, greatest width>1.5 × width at humeral angle. Elytron with 4 distinct costae; from suture, costa I arising from anterior margin and extending to 3/5 elytral length, costa II arising from anterior margin and extending to 4/5 elytral length, costa III arising from about 2/5 posterior to middle of anterior margin and extending to 4/5 elytral length, costa IV arising from humeral angle and extending to 4/5 elytral length; elytron with distinct, moderately deep punctation, 5–7 punctures between suture and costa I medially, becoming indistinct, shallower apically, subequal basally; elytron with moderate, recumbent pubescence, one seta per puncture, testaceous over testaceous integument, black over black integument, outer elytral margins with pubescence more dense and suberect. Metathoracic wing basal 1/ 5 lightly tinted, basal 4/5 darkly tinted.

Abdominal Sternites. Piceous, shining, finely punctate, covered in sparse, short, erect, black pubescence. Legs. Piceous, except basal ¾ of pro-femora testaceous. Femora and tibia minutely punctate, covered in sparse, erect and suberect, black pubescence, except ¾ of pro-femora with testaceous pubescence; tarsal pubescence recumbent to suberect and more dense. Metatibia straight, not strongly sinuate. Genitalia. Not examined for this species.

Intraspecific variation. Medial aspect of frons testaceous. Elytron with basal 4/5 testaceous and apical 1/5 piceous; piceous integument lacking violaceous sheen. This species is described from two female specimens. As with other species in this genus, polychromatism will likely be evident once more specimens become available for examination.

Phylogenetic relationship. This species is sister to E. nigripennis supported by the homoplasious character of the integument below the lower eye lobe less than 0.3 × height of the lower eye lobe (Character 2) ( Figs. 31 , 32 ).

Distribution. Mexico (Morelos) and Guatemala (Zacapa) ( Fig. 37 ).

Natural history. Flight period June.

Specimens examined. The holotype (here designated) and one paratype (♀) were examined. No males of this species are currently known.

Figures

FIGURE 31. Three of six most parsimonious trees retrieved from phylogenetic analysis of Elytroleptus (L = 59, CI = 50, RI = 75). Numbers above branches are characters and numbers below branches are character states. Characters are optimized for

FIGURE 32. Strict consensus for six most parsimonious cladograms resulting from cladistic analysis of Elytroleptus. Numbers above branches are Bremer support values.

FIGURE 37. Distribution map for Elytroleptus nigripennis, Elytroleptus pallidus, and Elytroleptus quadricostatus.