Rhinotragus monnei, Clarke, 2012

Clarke, Robin O. S., 2012, Bolivian Rhinotragini V: New Species Of Erythroplatys White, 1855, Rhinotragus Germar, 1824, Ornistomus Thomson, 1864, And Aechmutes Bates, 1867 (Coleoptera, Cerambycidae), Papéis Avulsos de Zoologia 52 (5), pp. 55-79 : 65-69

Rhinotragus monnei sp. nov.

Figs. 4A, 4B

Holotype male: 12.0 mm. Deposited at MNKM.

Diagnosis: R. monnei is readily separated from R. antonioi by colour distribution, as follows: in males interocular space and vertex of head yellowish (in R. antonioi these black in males; females may be yellow at centre of vertex); antennae almost entirely blackish (in R. antonioi almost entirely yellowish); pronotum yellow with U-shaped black fascia occupying most of disc (in R. antonioi pronotum is entirely black); basal two-thirds of elytra entirely yellow (in R. antonioi basal two-thirds bisected by transverse, black fascia); midline of underside broadly yellow from submentum to middle of metasternum (in R. antonioi pro-, meso-, and metasterna are entirely black).

The two species discussed above are easily distinguished from other Bolivian species of the genus by their colour distribution, and comparatively slender form. R. antonioi and R. monnei have head yellow, and apical third of elytra black (in both R. apicalis Guérin- Méneville, 1844 and R. dorsiger Germar, 1824 head black, elytral apex only narrowly black, form robust). R. monnei could be confused with R. dorsiger var. collaris Melzer, 1930 (which has similar U-shaped fascia on pronotum; but black head and narrower black elytral apex still serves to separate the latter species from the former). Both R. antonioi and R. monnei may be separated from R. lucasii Thomson 1861 by their dark legs, relatively slender form, and small size ( R. lucasii has yellow legs, robust form, and is consistently much larger).

Description of holotype: colour opaque black and translucent orange-yellow. Head orange-yellow, the following black: mandible; apex of gena; mentum-submentum; narrow fascia behind each superior lobe of eye; and antenna (only segments VII-XI inconspicuously yellow at base). Mouthparts, labrum and clypeus dusky. Prothorax orange-yellow, the following black: postcoxal process, from which an elongate fascia at extreme sides of pronotum projects anteriorly (but not reaching front margin of pronotum); and disc of pronotum occupied by broad horseshoe-shaped fascia (open end reaching front margin, closed end reaching hind margin). Centre of mesosternum (including its process) yellow, sides and mesepimeron black. Scutellum and apical third of elytra black, rest of elytra pale yellow. Metathorax black, except basal half of metasternum with bracket-shaped, orange-yellow fascia. Abdomen black, except midline of urosternite I occupied by diamond-shaped, orange-yellow fascia. Legs black, except coxae and oval fascia on mesal side of profemoral clave orange-yellow.

General pubescence: yellow. Upperparts almost glabrous, except: short, sparse, pubescence on frons and sides of pronotum; sterna almost entirely clothed by inconspicuous, very short, dense pubescence (less so on prosternum); but longer, erect, sparse hairs more noticeable on metasternum. Abdomen with dense, recumbent patches of short hairs at sides of urosternites I-IV and centre of V; and transverse rows of sparse, longer, erect hairs towards hind margins of each segment. Protibiae densely clothed with short, shining, golden pubescence mesally. Antennae setose, on segments I-III short and inconspicuous, on IV-VI with longer and thicker.

Surface ornamentation: dense and heavy on upperparts, variable on underside. Head with confused, smaller, punctures between elongate micro-carinae, the carinae larger on interocular space, and transverse on mentum-submentum. Large, deep, contiguous, alveolate punctures on the following: pronotum (except apical two-thirds of midline and basal angles almost completely smooth); apical third of elytra, and along humero-apical costa (on rest of elytra the punctures shallower). Sterna with moderately dense, large, round punctures; the interstices micropunctate in areas densely pubescent, smooth in areas generally glabrous (especially sides of metasternum and most of metepisternum). Abdomen micro-reticulate with small, rather sparse, shallow punctures, becoming denser below thicker pubescence, and larger at midline of urosternite I. Legs generally smooth and impunctate to sparsely punctate on femora (their dorsal surfaces with bevelled, setose punctures), but large and confluent at apices of femora, and all tibiae.

Structure: medium sized species, with elytra narrowing to apex; forebody 1.22 longer than abdomen (5.10 mm). Head with eyes (1.75 mm) distinctly narrower than width of prothorax. Rostrum long (0.6 mm), widest (1.15 mm) at apex. Labrum projecting; moderately large (wider than apex of clypeus); rectangular (with rounded sides and almost truncate apex); about twice as wide as long; with scattered punctures at base. Clypeus separated from frons by wide declivity; with sparse fine punctures almost to front margin. Eyes rather small, rounded; inferior lobes of eyes longer (0.75) than genae (0.6 mm); their proximal margins lying close to sides of genae, distal margins slightly oblique; width of one inferior lobe 1.75 times interocular space (0.40 mm).

Superior lobes with 12-13 rows of fine ommatidia; separated by (0.55 mm) slightly more than twice their own width. Apex of antennal tubercles rounded, and separated by twice width of scape (0.3 mm). Antennae rather short, reaching base of urosternite II; antennomeres somewhat thickened, VI-X incrementally serrate (the apical angles moderately acute); scape fusiform, with regular rows of fine, close punctures, shorter (0.95 mm) than antennomere III; III cylindrical, distinctly longer (1.25 mm) than rest; IV short (0.50 mm); V and VI equal (0.75 mm); VII (0.70 mm); VIII-X progressively shorter, X (0.55 mm); XI (0.65 mm) with small apical cone. Prothorax subquadrate, 1.09 longer than wide; sides not strongly rounded; more contracted in front (1.80 mm wide) than behind (2.15 wide), and widest at middle; apical constriction distinct but not strong; basal constriction narrow, not strongly declivous (more so laterally), with large fovea adjacent to hind angle. Pronotum strongly convex (obliterating the calli very evident in the female, with its less convex pronotum, as described below); front margin elevated and strongly bordered; hind angles almost right-angled. Prosternum almost planar from front margin to middle of prosternal process, the latter with apical half moderately inclined upwards; base of prosternal process with thick, raised borders, and relatively wide (0.25 mm), about one third width of coxal cavity; apical half large and triangular (with straight apical margin). Procoxal cavities almost ovate, closed at sides and behind. Mesosternum with deep, abrupt declivity. Base of mesosternal process strongly depressed along midline, sides strongly elevated and thickened anteriorly; relatively broad (0.40 mm), more than half width of coxal cavity. Apex of process bilobed, the lobes moderately short, slightly diverging, and separated by short notch. Mesocoxal cavities open to epimeron; mesepimeron wide at base and narrow towards apex, sinuate and constricted at middle. Scutellum narrow, sides slightly excavate, apical half slightly tumid (almost lobate), apical margin almost straight. Elytra hiding sterna; flat and depressed to inside of humeri (leaving basal margin slightly more prominent than humeri); elongate (apex just reaching base of urosternite V), 2.73 longer than width of humeri (2.55 mm); humeri not prominent, nor projecting, but almost right-angled. Each elytron regularly narrowed from behind humerus to apex, but weakly constricted at middle (at which point elytra become slightly elevated and divergent (i.e. start to gape), leaving apices well apart. Elytral apices obliquely truncate; sutural margin the shortest, and toothed by short extension of sutural border; lateral margin similarly extended by widening of its border. Elytral surface divided by distinct, broad, humero-apical costa; epipleura gradually flattened from just behind shoulders to apex. Sides of metathorax almost parallel, hind margin oblique. Metasternum large and convex (flattened towards midline), planar with pro- and mesocoxae; with complete longitudinal suture (deep behind, but shallow and narrow to front). Metepisternum partly overlapped by elytra, moderately wide, widest at base, moderately acuminate to apex. Abdomen not robust, somewhat flattened, regularly narrowing to apex; urosternites II-IV equal in length, strongly transverse, with rounded sides. Urosternite V hardly shorter; trapezoidal; with horseshoe-shaped depression occupying apical two-thirds, the sides of this depression slightly raised at apex; the apices acute and slightly projecting; apical margin slightly bisinuate with narrow, raised border. Abdominal process planar with abdomen; triangular; sides hardly raised; apex moderately acuminate, not intimately inserted between metacoxae. Apical tergite far from overlapping apex of urosternite V; elongate; rather narrow; with sides slightly excavate; apical margin characteristic (divided by narrow incision into two, separately rounded halves). Legs moderately robust; ratio length front to hind leg 1.0:1.3:1.6; front and middle legs strongly pedunculate-clavate (sides of mesofemoral peduncle, and lateral side of clave flattened at sides). Hind leg more cylindrical; clave long and fusiform (not abrupt), apex reaching apex of urosternite IV; peduncle cylindrical slightly more than half length of clave. Protibia with apex obliquely excised laterally, front margin not prominent at middle, shorter (2.0 mm) than mesotibia (2.3 mm); metatibia (3.6 mm) not much shorter than metafemora (4.0 mm), bisinuate, gradually thickened to apex, the latter clothed with short, dense, brownish pubescence mesally. Protarsus shorter (1.50 mm) than mesotarsus (1.70 mm), both shorter than metatarsus (1.90 mm); metatarsomere I short (0.55 mm), much shorter than II + III (0.85 mm).

Variation in males: the two male paratypes only show minor differences from the holotype: in one the horseshoe-shaped fascia is interrupted near base by lack of pigmentation; the bracket-shaped, yellow fascia on metasternum is narrower, and the yellow fascia on urosternite I is limited to the abdominal process. In one male the rostrum is parallel-sided, and latero-apical angles of elytra more rounded.

Description of female ( Fig. 4B ): there are no significant differences of colour (except antennae entirely blackish, urosternite I more broadly yellow, and II yellow at midline in one female), or surface features (including lack of sexual puncturation) from the male; and structural differences seem to be limited to sexually dimorphic ones usual in species of this tribe.

Structure: most structural differences limited to sexually dimorphic ones usual in species of this tribe. Width of one inferior lobe of eye 1.08 times interocular space (0.65 mm); distal margins of lobe oblique; superior lobes of eyes separated by about twice their own width. Antennae shorter than in male, reaching middle of urosternite I; antennomere III is thicker, and VII-X subserrate (the apical angles obliquely clipped). Apical constriction of prothorax not quite as strong as in male; and side margins rendered more irregular by two weakly projecting calli on pronotum (one at middle of sides, the other overhanging side of basal constriction). Scutellum tumid as in male (but with round depression centred on apex), and slightly more quadrate. Abdomen more robust, deeper and broader than in male; from urosternite III narrowing to apex; V undifferentiated, with slightly rounded apical margin, and group of small punctures at centre. Apical tergite cone-shaped, but not long, densely punctured, especially at apex. Ratio length front to hind leg 1.0:1.3:1.5; mesofemoral clave less tumid than in male; and apex of metafemoral clave reaching base of urosternite IV; otherwise legs similar to male.

Measurements (mm): 3 males / 2 females: total length, 11.60-12.00/12.9-13.0; length of pronotum, 2.25-2.55/2.50-2.55; width of pronotum, 2.10-2.30/2.40; length of elytra, 6.25-6.95/7.00-7.40; width at humeri, 2.25-2.55/2.60-2.65.

Type material: Holotype male, BOLIVIA, Santa Cruz, Hotel Flora & Fauna, 5 km SSE of Buena Vista , 17°29’96”S/ 63°39’13”W, 430 m, on/flying to flowers of “Sapaimosi”, 20.XII.2006, R. Clarke & S. Zamalloa col. ( MNKM).

Paratype with same data as holotype: 1 male, 21.XII.2005 ( MNRJ) .

Paratypes with same data as holotype, but different hostflowers: on/flying to flowers of “Piton amarillo”, 1 female, 21.X.2005 ( RCSZ); on/flying to flowers of “ Barbasquillo B ”, 1 male, 28.X.2007 ( RCSZ); on/ flying to flowers of “Tutumillo espinoso”, 1 female, 23.XI.2009 ( MZUSP) .

Etymology: this species is named in honour of Dr. Miguel A. Monné for his work on the Cerambycidae .

Figures

FIGURES 3‑4: 3, Rhinotragus antonioi sp. nov.: A male holotype, B female paratype. 4, Rhinotragus monnei sp. nov.: A male holotype, B female paratype.