Dendrobias steinhauseni ( Hüdepohl, 1987 ) Vlasak & Santos-Silva, 2018

Vlasak, Josef & Santos-Silva, Antonio, 2018, New genus, species, redescription, and new rank in Cerambycinae (Coleoptera, Cerambycidae), Zootaxa 4446 (3), pp. 384-396 : 392-395

Dendrobias steinhauseni ( Hüdepohl, 1987) , comb. nov.

Trachyderes ( Dendrobias ?) steinhauseni Hüdepohl, 1987: 199 .

Trachyderes (Dendrobias) steinhauseni ; Monné, 1994: 100 (cat.); Monné & Giesbert, 1994: 154 (checklist); Turnbow et al., 2003: 18 (distr.); Monné, 2005: 653 (cat.); Monné & Hovore, 2005: 153 (checklist); 2006: 152 (checklist); Swift et al., 2010: 33 (distr.); Maes et al., 2010: 624 (distr.; female holotype only); Monné, 2018: 964 (cat.).

Trachyderes steinhauseni ; Chemsak et al., 1992: 87 (checklist).

Trachyderes (Dendrobias) maxillosus ; Maes et al., 2010: 622, 623. (Error of identification).

Trachyderes (Dendrobias) sp.; Maes et al., 2010: 626 (distr.).

Trachyderes (Trachyderes) elegans ssp. elegans ; Maes et al., 2010: 628 (only female on the upper side of the page; error of identification).

Oxymerus aculeatus ssp. lebasii (only figure at the right side); Maes et al., 2010: 602. (Error of identification).

Description. Male ( Figs 10–17 ). Integument mostly brownish-black; scape, pedicel and antennomere III from black to dark brown; antennomeres IV–XI from reddish brown to yellowish on basal area, from black to dark brown on distal area (this latter area gradually reduced from IV to X); elytra from reddish brown to yellowish brown (probably it may also be entirely black as in some females), with four longitudinal, narrow yellowish bands (sometimes, slightly conspicuous); femoral peduncle reddish brown, and femoral club black; tibiae mostly from reddish brown to yellowish brown, darkened near apex; tarsi form reddish brown to brown; narrow distal area of abdominal ventrites I–IV dark reddish brown.

Head. Frons vertical, gradually and slightly inclined backward toward clypeus; rugose, distinctly depressed when compared with area under antennal tubercles; nearly glabrous. Frontal area under antennal tubercles moderately coarsely, densely, confluently punctate; with short, decumbent, sparse yellowish-white setae. Vertex depressed from antennal tubercles to after eyes (continuing behind upper eye lobes), but distinctly divided into two isolated areas by the median groove and elevated area centrally between upper eye lobes (this elevated area as continuation of median groove); depressed area finely, sparsely punctate between antennal tubercles, nearly smooth on remaining surface; with minute, sparse, decumbent yellowish-white setae. Remaining surface of vertex finely, sparsely punctate close to depressed area, finely striate-punctate close to prothoracic margin; with minute, decumbent, sparse yellowish-white setae. Area behind upper eye lobes close to prothorax finely striate-punctate; area behind lower eye lobes distinctly gibbous centrally; finely, abundantly punctate on gibbosity, nearly smooth close to prothorax and eye; with short, decumbent, moderately sparse golden or pale-yellow setae on gibbosity and close to eye, glabrous on remaining surface. Genae moderately coarsely, abundantly punctate; with short, sparse golden or pale-yellow setae. Antennal tubercles triangularly elevated toward upper eye lobes, with blunt apex; finely, abundantly punctate except smooth narrow distal area; with short, sparse, decumbent yellowish setae. Median groove distinct form clypeus to between upper eye lobes. Postclypeus slightly inclined at wide basal area, abruptly inclined at narrow distal area; coarsely, abundantly, confluently punctate on wide central area, smooth laterally; with short, sparse sub-erect yellowish setae. Labrum coplanar with anteclypeus at basal 2/3, inclined at distal third; finely, abundantly punctate on basal third; with short, sparse yellowish setae on basal 2/3, long, abundant, golden setae directed forward on distal third. Submentum smooth, glabrous at about basal half close to prothorax, distinctly depressed, finely, abundantly punctate, with long, erect, translucent setae on distal half. Distance between upper eye lobes 0.56 times length of scape; ventrally, distance between lower eye lobes 1.46 times length of scape. Antennae 2.65 times elytral length, reaching elytral apex near apex of antennomere VII (only one specimen measured); scape coarsely rugose-punctate on basal half, gradually finely and sparsely punctate toward smooth apex; antennomere III gradually widened toward apex, slightly flattened from middle, with minute, abundant asperities throughout, except on smooth apex, which forms nearly acute angle at outer side; antennomeres IV-VIII cylindrical at basal 3/4, slightly widened at distal quarter, with outer angle forming acute angle; antennomeres IX-X not expanded at apex; antennomere XI curved at distal third (area at base of curvature usually with slight constriction); antennal formula (ratio) based on length of antennomere III (only one male measured): scape = 0.71; pedicel = 0.15; IV = 0.96; V = 0.91; VI = 0.93; VII = 0.86; VIII = 0.81; IX = 0.84; X = 0.83; XI = 1.27.

Thorax. Prothorax 1.45 times wider than long (including lateral tubercles). Pronotum with basal sulcus wellmarked (less so centrally); centrobasal depression large, nearly reaching transverse central keel; anterior margin of transverse keel with sides rounded, projected forward, and central area gradually inclined, projected forward into distal depression; with pale-yellow pubescence not obscuring integument, denser laterally, distinctly sparser centrally, especially on basal gibbosities and into distal depression. Sexual punctation on prosternum distinct on basal 2/3 except smooth central area; central tubercle distinctly projected; transverse depression from very deep with margin close to prosternal process nearly vertical ( Fig. 12 ) to moderately deep with margin close to prosternal process gradually inclined ( Fig. 16 ); with both short and long, bristly pale-yellow setae on punctate area, nearly glabrous centrally between sexual punctation, with bristly pale-yellow setae on distal third, sparser than on punctate area. Distal apex of prosternal process distinctly, triangularly projected; sides with pale-yellow bristly setae, glabrous centrally. Mesoventral process with moderately short tubercle projected toward mesoventrite; posterior margin deeply emarginate; with slightly bristly pale-yellow setae laterally, glabrous centrally. Ventral side of mesothorax with pale-yellow pubescence not obscuring integument, slightly denser laterally. Metanepisternum and sides of metaventrite with pale-yellow pubescence not obscuring integument; central area of metaventrite with long (sometimes slightly short), erect, sparse pale-yellow setae. Scutellum nearly glabrous. Elytra. Minutely, moderately abundantly punctate throughout, somewhat rugose distally; with minute pale-yellow setae laterally, gradually denser toward apex; remaining surface with nearly inconspicuous, very sparse pale-yellow setae; elytral apex very slightly sinuous, truncate. Legs. Femora finely sparsely punctate basally, gradually denser toward apex of club (especially on meso- and metafemora); with short, sparse pale-yellow setae, denser ventrally on club of mesofemora, and dorsally and ventrally on metafemora.

Abdomen. Ventrites I–IV with short pale-yellow pubescence, denser laterally (they could be nearly glabrous centrally); ventrite V with short pale-yellow pubescence throughout; apex of ventrite V slightly emarginate centrally.

Female ( Figs 18–25 ). Elytra with same color variation as in male or entirely black. Antennae from 1.45 to 1.50 times elytral length, from almost reaching to slightly surpassing elytral apex; basal antennomeres with wide orange ring on basal half, black or nearly so on remaining areas; antennomeres VII–VIII from bicolorous to nearly entirely dark; antennomeres IX–XI from bicolorous to entirely orange or yellowish-brown.

Dimensions in mm (2 males / 2 females). Total length, 21.5–26.1/25.9–26.2; elytral length, 13.3–15.3/16.0– 16.2; humeral width, 7.0–8.0/8.3–8.4; pronotal length, 4.7–5.2/5.2–5.3; pronotal width, 6.8–7.7/7.7–7.8.

Material examined. NICARAGUA, Granada: Domitila, 1 female, 17-21.XII.2004, E. van den Berghe col. ( DHCO). Masaya: vic. Laguna de Apoyo, 1 male, 19.XI.1992, E. van den Bergh ecol. ( DHCO). COSTA RICA, Guanacaste: Santa Rosa, 1 male, 1 female, 2.VIII.2014, J. Vlasak col. ( MZSP).

Remarks. Dendrobias steinhauseni (male) in Maes et al. (2010: 624) is a male of Trachyderes . The photographs do not allow determination of the species. We know that the specimens reported as T. (D.) steinhauseni by Maes et al. (2010), belonging to Daniel Heffern collection, are true specimens of this species. However, we do not know if the specimen mentioned in this work as belonging to Diethard Dauber collection is Dendrobias steinhauseni , but apparently it is a female of this species. On the other hand, the specimen belonging to Museo Entomológico de León ( Isla de Ometepe) is, without a doubt, a male of Trachyderes , and not Dendrobias steinhauseni .

Maes et al. (2010: 602) also reported a specimen figured as Oxymerus aculeatus lebasii Dupont, 1838 : “ Nicaragua: Granada: Domitila, en trampas de piña, 18-XII-2004, col. Eric van den Berghe. Este specímen parece más bien un Trachyderes , más aun con las antenas bicolores.” We agree: the specimen is a female of Dendrobias steinhauseni . Maes et al. (2010) also figured three females as being Trachyderes (Dendrobias) maxillosus Dupont, 1834 . Actually, they are all females of Dendrobias steinhauseni . Females of Dendrobias maxillosus have the antennae distinctly surpassing elytral apex (not or slightly surpassing in D. steinhauseni ), and pronotum does not have pubescence (pubescent in D. steinhauseni ). Finally, Maes et al. (2010: 628) illustrated a female, upper side of the page, as being Trachyderes (Trachyderes) elegans elegans ( Dupont, 1836) . This specimen is a female of D. steinhauseni .

The first who reported Dendrobias maxillosus from Nicaragua was Bates (1872): “ Dendrobias maxillosus, Serville, Ann. Soc. Ent. Fr. 1834 , p. 44.—A specimen sent home by Mr. Belt is much larger than the insect described by Serville; viz., 12 lin. [25.44 mm] instead of 9 lin. [19.08 mm]” According to Villiers (1980) (translated): “Mentioned from Nicaragua, without doubt, by confusion with a concolorous variety of D. mandibularis .” It’s possible that the species is D. steinhauseni . Unfortunately, it is not possible to be sure without examining the specimen studied by Bates (1872), currently deposited in the MNHN.

Monné & Hovore (2005) and Monné (2005) listed D. steinhauseni from Honduras and Costa Rica. This information is a compilation of Monné & Hovore (2001). Monné & Hovore (2006) recorded the species from Honduras, Nicaragua and Costa Rica. After this, Swift et al. (2010), Maes et al. (2010), and Monné (2018) also listed the species from these three countries.

The first author observed that the longitudinal yellowish lines on elytra are quite distinct in living specimens of Dendrobias maxillosus and, to a lesser degree, in D. mandibularis , but they disappear to a varying degree depending on how the beetle was dried and can disappear completely in some specimens. It is very probable that the same occurs in specimens of D. steinhauseni .

Figures

FIGURES 10–17. 10–13, Dendrobias steinhauseni, male, specimen 1: 10, Dorsal habitus; 11, Ventral habitus; 12, Lateral habitus; 13, Head, frontal view. 14–17, D. steinhauseni, male, specimen 2: 14, Dorsal habitus; 15, Ventral habitus; 16, Lateral habitus; 17, Head, frontal view.

FIGURES 18–25. 18–21, Dendrobias steinhauseni, female, specimen 1: 18, Dorsal habitus; 19, Ventral habitus; 20, Lateral habitus; 21, Head, frontal view. 22–25, D. steinhauseni, female, specimen 2: 22, Dorsal habitus; 23, Ventral habitus; 24, Lateral habitus; 25, Head, frontal view.