Oideterus elegans ( Waterhouse, 1880 )

Vlasak, Josef & Santos-Silva, Antonio, 2022, Descriptions, notes, and a new record in Oideterus Thomson (Coleoptera, Cerambycidae, Prioninae, Anacolini), Zootaxa 5175 (5), pp. 535-547 : 536-539

Oideterus elegans ( Waterhouse, 1880)

( Figs 1–11 )

Udeterus elegans Waterhouse, 1880: 290 ; Lameere, 1883: 8 (cat.); 1912: 102; 1913: 91 (cat.); 1919: 170; Blackwelder, 1946: 557 (checklist); Galileo, 1987: 561; Monné & Giesbert, 1994: 20 (checklist); Monné, 1995: 74 (cat.); Monné, 2006: 28 (cat.).

Oideterus elegans ; Galileo & Santos-Silva, 2015: 399 (key); Monné, 2021: 74 (cat.).

Descripition. Male ( Figs 1–8 ). Head capsule, mandibles, antennae, prothorax, most of ventral surface of mesothorax, and scutellum bluish black, with metallic greenish reflections on frons and prothorax; palpomeres mostly blackish with irregular brown areas, lighter on apex of some palpomeres. Metanepisternum brownish. Metaventrite yellowish-brown, except blackish anterocentral margin, and brownish area close to metacoxae. Elytra orangish brown basally, this area slightly widened from humerus to suture, bluish black on remaining surface. Femora and meso- and metatibiae yellowish brown; metatibiae metallic dark brown, with bluish reflections on basal half, gradually yellowish-brown toward apex; tarsomeres I–II mostly yellowish brown; tarsomeres III brownish; pro- and mesotarsomeres IV–V dark yellowish brown, more brownish on apex of V; metatarsomeres IV–V dark brown with metallic bluish reflections. Ventrite 1 brownish; ventrite 2 mostly yellowish brown; ventrite 3 yellowish brown with brown apex; ventrites 4–5 metallic blackish with bluish and greenish reflections.

Head. Frons, vertex, and area behind upper eye lobes coarsely, densely punctate; with abundant, erect, moderately long yellowish-brown setae on frons, and moderately abundant, short, erect yellowish-brown setae on vertex and area behind upper eye lobes. Antennal tubercles coarsely, shallowly punctate, punctures gradually slightly finer toward smooth apex; with erect setae as on frons, except glabrous smooth area. Area behind lower eye lobes smooth and glabrous close to eye, coarsely (punctures coarser than behind upper eye lobe), somewhat asperate-punctate with abundant, erect, moderately long yellowish-brown setae. Genae almost smooth close to clypeus, coarsely, somewhat sparsely punctate on remaining surface; with short, sparse yellowish-brown setae on punctate area, glabrous on smooth area. Wide central area of clypeus minutely striate with a few coarse and shallow punctures centrally close to frons, abundantly, coarsely punctate on remaining surface, punctures shallower than on frons, except smooth anterior region; with long, erect, sparse yellowish-brown setae, except glabrous central area close to frons. Side of clypeus smooth, glabrous. Labrum with long, erect, sparse yellowish-brown setae. Gulamentum smooth, glabrous on posterior third; remaining surface coarsely, densely, somewhat shallowly striate-punctate, with long, erect yellowish-brown setae. Distance between upper eye lobes (only one male measured) 0.41 times distance between outer margins of eyes; in frontal view, distance between lower eye lobes 0.67 times distance between outer margins of eyes. Antennae 3.25 times elytral length, reaching elytral apex at posterior third of antennomere V. Scape wide, dorsoventrally flattened on anterior 2/3, tumid on posterior third; coarsely, shallowly, sparsely punctate; with short, sparse yellowish-brown setae. Antennomere III without apical projection; antennomere IV with projection on outer apical angle as long as 1/3 of length of antennomere; antennomeres V–X with projection on outer apical angle, longer than length of antennomere (proportionally longer toward X); antennomere XI distinctly widened from base to about middle, then subparallel-sided. Antennal formula (ratio) based on length of antennomere III (not including projection of IV–X; only one male measured): scape = 0.50; pedicel = 0.14; IV = 0.77; V = 0.49; VI = 0.45; VII = 0.42; VIII = 0.40; IX = 0.39; X = 0.39; XI = 0.93.

Thorax. Prothorax wider than long, even excluding lateral tubercles; lateral tubercles large, conical, located centrally; posterior margin sinuous, with central area slightly projected backward and emarginate centrally. Pronotum with slightly distinct gibbosity on each side of wide central area; coarsely, densely punctate, with diameter and depth of punctures not uniform, except smooth apex of anterior region of gibbosities; with abundant, long, erect yellowish-brown setae. Prosternum abundantly, coarsely, shallowly punctate laterally, punctures slightly finer and deeper centrally, except smooth posterocentral area; with long, erect yellowish-brown setae, except glabrous smooth area. Prosternal process reaching about middle of mesocoxae, subparallel-sided on anterior 3/4, distinctly narrowed on posterior quarter; width on middle 1.35 times narrowest length of prosternum. Sides of ventral surface of mesothorax with long, erect, somewhat sparse yellowish-brown setae. Metanepisternum abundantly, coarsely, shallowly punctate; with abundant, long, erect pale-yellow setae. Metaventrite with abundant, long, erect paleyellow setae not obscuring integument; metathoracic discrimen distinct from base to apex. Scutellum coarsely, densely punctate; with a few short yellowish setae. Elytra. Slightly surpassing base of second visible abdominal segment; strongly dehiscent and concave along sutural margin; apex rounded; coarsely densely punctate, except almost smooth humeral area; glabrous. Legs. Femora with short, sparse pale-yellow setae except basal 2/3 of ventral surface with abundant, erect, long pale-yellow setae. Tibiae with short, bristly yellowish setae, more abundant toward apex, especially on protibiae, and more yellowish brown on basal half of metatibiae. Metatarsomere I slightly longer than II–III together.

Abdomen. Ventrites 1–4 with both short and long, decumbent yellowish-brown setae, more abundant on ventrite 4; ventrite 5 with somewhat abundant, short brownish setae, longer laterally and apically.

Chromatic variation in males. Orangish brown basal band on the elytra variable in length and width ( Figs 1 , 6–8 ); metatibiae almost entirely yellowish brown.

Females ( Figs 9–11 ). Similar to male, differing by shorter antennae, although somewhat variable in length, with shorter and wider flabellae, and the longer elytra.

Chromatic variation in females (not including the holotype ( Fig. 9 )). Elytra entirely metallic dark blue ( Fig. 10 ) or with wide orangish brown basal band ( Fig. 11 ); mesotibiae entirely blackish or with yellowish-brown posterior half.

Dimensions in mm (males/females). Total length, 11.25–14.45/15.45–15.75; prothoracic length, 1.50– 2.10/2.05–2.10; anterior prothoracic width, 1.80–2.55/2.55–2.60; posterior prothoracic width, 1.70–2.45/2.90–2.95; maximum prothoracic width, 2.40–3.75/4.20–4.25; humeral width, 3.20–4.60/5.20–5.30; elytral length, 4.50– 6.15/9.35–9.90.

Material examined. ECUADOR, Napo (new province record): Cosanga , 1900 m, 4 males, 2 females, 14. VI .2021, J. Vlasak leg. (2 males, MZSP; 2 males and 2 females, JVCO) .

Remarks. The holotype has the head and prothorax reddish brown and the elytra mostly orangish. However, it is possible to see that the basal area of the elytra is distinctly paler. This distribution of colors agrees well with that in the males examined, and also with one of the females. Furthermore, the color in many (probably all) species of Oideterus is very variable (see, for example, the variation in O. dichotomus on Bezark 2022 and Pirkl 2022). The proportions and length of antennomeres III and IV in the males agree well with those in the holotype and the two females examined. Finally, although the holotype is from a different place, both the type locality (Morona-Santiago, Chiguinda) and Cosanga (Napo) are located on the eastern slopes of the Andes Mountains in Ecuador, only about 300 km apart and at a similar altitude of approximately 2,000 m. Furthermore, one male (specimen 2, Fig. 6 ) and the two females ( Fig. 7 and 8 ) were all reared from the same decayed vine (about 3 cm in diameter), which confirms that they belong to the same species. With the combination of these factors, we therefore conclude that the specimens described here are males of O. elegans .

Figures

FIGURES 1–5. Oideterus elegans (Waterhouse, 1880), male (specimen 1): 1) Dorsal habitus; 2) Ventral habitus; 3) Lateral habitus; 4) Head, frontal view; 5) Prosternal process.

FIGURES 6–11. Oideterus elegans (Waterhouse, 1880), dorsal habitus: 6–8) Males: 6) Specimen 2; 7) Specimen 3; 8) Specimen 4. 9–11) Females: 9) Holotype female; 10) Specimen 1; 11) Specimen 2.