Rhinobatesia Clarke, 2018

Clarke, Robin O. S., 2018, Provisional revision of the genus Odontocera Audinet-Serville, 1834 (Coleoptera: Cerambycidae). I: exclusions, new rank, synonymies and the description of two new genera, Insecta Mundi 637, pp. 1-27 : 14-18

Rhinobatesia Clarke , n. gen.

Fig. 35–36

Type species. Odontocera rugicollis Bates, 1880 , here designated.

Description of the genus. Robust species, length body/width metasternum in male 5.16, in female 4.58. Lengths forebody/abdomen 1.01 in male, 1.30 in female.

Head. Head (h) narrower than prothorax (p), p/h 1.21 in male, 1.13 in female. Rostrum almost parallelsided (but widest at apex) long, width/length 1.61 in male, 1.68 in female. Labrum moderately large, almost rectangular; approximately 2× wider than long, apical margin truncate and not declivous. Surface of clypeus hardly differentiated from frons, both with similar surface ornamentation. Frons depressed, separated from clypeus by ill-defined declivity; coronal suture only traceable on interocular. Area of submentum depressed; separated from gula by distinct declivity in male, less declivous in female.

Eyes. Inferior lobes of eyes not contiguous, width of one lobe/interocular 3.40 in male, 2.00 in female; strongly convex laterally; mesally slightly more prominent than interocular; distal margins adjacent to genae, proximal margins almost transverse. Superior lobes not widely separated, interocular distance/ width of one lobe 2.33 in male, 2.50 in female; with approximately 13 transverse rows of ommatidia, reduced to approximately 7 rows laterally in male, 8 in female.

Antennal tubercles. Prominent, but rounded, comparatively widely separated, in male 0.7 mm, in female 0.85 mm; tubercular space/width of scape 1.56 in male, 1.70 in female.

Antennae. Crassate, short, reaching metacoxae in male, middle of urosternite I in female; antennomeres widest from V to IX; VI—X with acute, clipped serrations, and XI subserrate. Scape robust and wide, pyriform, nearly 3× longer than pedicel in male, more than 3× longer in female; approximately 1/3 shorter than antennomere III; antennomere III at least 1.4× longer than any other segment, almost cylindrical, slightly narrower than pedicel at base, wider than pedicel at apex. In males: IV and V gradually widened to apex; V almost subserrate; VI–X narrow at base, strongly widened to apex, incrementally shorter; XI in male basically short and subcylindrical, but with apical cone displaced laterally, the mesal side appears abruptly dentate. In female: basal segments tend to be longer than in male, and apical ones shorter; IV–X similar in structure, but somewhat tumid compared with males; and XI hardly dentate as apical cone not displaced. Lengths (mm) antennal segments, male and female, as follows: scape, 0.85, 1.00; pedicel, 0.30; III, 1.25, 1.45; IV, 0.75, 0.85; V, 0.90, 1.00; VI, 0.85, VII, 0.80, 0.75; VIII, 0.70, 0.65; IX, 0.65, 0.60; X, 0.50; XI, 0.70.

Prothorax. Subcylindrical, length/width 1.28 in male, 1.24 in female; in male sides regularly and weakly rounded to basal constriction, in female straight and parallel-sided for apical half, rounded for basal half; in male widest slightly in front of middle (prothoracic quotient 2.14), in female widest slightly behind middle (prothoracic quotient 1.85); surface almost regular (but vestigial calli and depressions overlaid by rugose puncturation); apical constriction evanescent, basal constriction not abrupt (sloping from basal margin to pronotal disk); towards sides with large, deep, rounded fossa; front margin slightly narrower than basal margin in male, of equal width in female. Prosternum declivous across apical third, strongly inclined to base of prosternal process; base of prosternal process arced, short and broad, in male 4.0× narrower than width of coxal cavity, in female 3.8× narrower; apex an equilateral trapeze, large and strongly rugose, with irregular tubercle occupying center; postcoxal process moderately narrow (approximately 0.25 mm), firmly closing coxal cavities.

Mesothorax. Mesosternum deep and abruptly declivous; base of mesosternal process V-shaped, 2.5× narrower than width of coxal cavity in male, 1.5× narrower in female; in male apex weakly bilobed, each lobe small, short and rounded at apex, in female lobes larger, longer and slightly divergent; coxal cavities narrowly open to moderately narrow mesepimeron. Mesothorax shorter than metathorax (the latter unusually long), lengths meso/meta 0.58 in male, 0.60 in female. Scutellum . Moderately large; trapezoidal, truncate at apex (in female bifid at apex).

Elytra. Strongly subulate, weakly, but widely fissate for apical two-thirds; flat (except for humeri and narrow, vertical epipleura); elongate (apex reaching from base to middle of urosternite IV); in male 2.76 longer than width of humeri, in female, 2.67 longer; humeri unusually broad (yet failing to hide sides of mesosternum when viewed from directly overhead), not projecting, moderately prominent; humeroapical costa absent. Each elytron strongly narrowed for basal half, narrow and almost parallel-sided for apical half. In male, sides of each elytron arced and narrowed from humerus to middle, weakly recurved for apical half, in female, arced to apex (but weakly so for apical half); apical margin obliquely truncate (sutural margin the longest) and unarmed.

Metathorax. Sides weakly rounded to apex, apex truncate, in female sides slightly more rounded and apex weakly oblique to midline; metasternum tumid, not flattened in male, broadly flattened in female; coplanar with mesocoxae in female, slightly lower than mesocoxae in male. Metepisternum: cuneate, in male moderately broad at base, strongly narrowed to acuminate apex, in female base broader.

Abdomen. Male. cylindrical (weakly apiform), moderately elongate and broad, convex, weakly annulate. Urosternites I–IV: cylindrical, sides weakly converging to apex; I with sides weakly rounded, II–IV with sides straight; broadest (1.8 mm) at base of I, narrowest (1.5 mm) at apex of IV. Urosternite I distinctly longer than the others, quadrate, II slightly transverse and weakly trapezoidal; III quadrate; IV transverse. Length (mm) urosternites: I, 1.85; II, 1.50; III, 1.55; IV, 1.30. Urosternite V (0.90 mm), when viewed from below: trapezoidal, quadrate, with weakly rounded sides; soleate depression represented by large, oval shallow area demarcated by broad, rounded weakly raised sides; apical margin bisinuate; hind angles (when viewed laterally) subacute, wide wings, not projecting beyond apical margin. Abdominal process an equilateral triangle, with 10° slope, intimately inserted between metacoxae (with short, straight extension at apex).

Female. fusiform, moderately broad, hardly flattened; not annulate. Urosternites I–V: I-III cylindrical, IV–V trapezoidal; sides weakly rounded; I–II with sides weakly widening to apex, III–V converging to apex; broadest (2.5 mm) at middle of II, narrowest (0.8 mm) at apex of V. Urosternite I much longer than the others, slightly transverse; II–V transverse; V not down-turned. Length (mm) urosternites: I, 2.15; II, 1.35; III, 1.30; IV, 1.05; V, 0.90. Abdominal process large and coplanar with abdomen.

Apical tergite. Moderately long (approximately 1.5 mm) in both sexes; in male, cylindrical, convex, apex excavate; in female, trapezoidal, flat; apex rounded.

Legs. Moderately long and robust, ratio of length from front to hind leg 1.0:1.2:1.8–2.1. Front leg. Femoral peduncles unusually long; clave fusiform, strongly tumid mesally (hardly so laterally) and abrupt; tibia narrow at base, regularly widening to apex; apex obtusely excised laterally, mesally without tooth. Middle leg. Femora relatively long, 1.42–1.45× longer than tibiae; clave fusiform, slightly longer than peduncle, lengths clave/peduncle 1.10–1.15, tumid, more so mesally (when viewed from above), moderately wide dorso-ventrally, length of femur/width of clave 3.39 in male, 3.94 in female; peduncle flattened; tibia weakly sinuate near apex, hardly flattened, gradually widening from middle to apex; pro- and mesotarsi similar; moderately robust, short, widening to apex, tarsomere I trapezoidal, hardly elongate, II trapezoidal, transverse, III wide and strongly bilobed. Hind leg. Femoral clave subabrupt, fusiform; apex reaching basal third of urosternite IV in male, in female apex of IV; clave distinctly shorter than peduncle, lengths clave/peduncle 0.91 in male, 0.87 in female; peduncle cylindrical, moderately narrow; tibia cylindrical, in male weakly sinuate when viewed from directly behind, straight when viewed from the side, in female straight viewed from behind, bisinuate when viewed from the side; shorter than femora, lengths femur/tibia 1.07—1.10; gradually thickened from middle to apex, rather densely setose for apical half (the setae rather too short to be called a brush); metatarsus similar to pro- and mesotarsi, but differs by longer first and second tarsomeres; metatarsomere I subcylindrical, short in male, 0.94 length of II+III, very short in female, 0.74 length of II+III; II trapezoidal, weakly pediculate; III broad and deeply bilobed; onychium long, but not slender.

Male genitalia ( Fig. 51 ). Median lobe (length approximately 1.7 mm) moderately broad and arced, acuminate to apex (when viewed laterally); internal sack seems to lack dark bodies. Tegmen. chitinized, with paired, weakly divergent, finger-like lateral lobes. Each lobe: moderately long, approximately 3× longer than basal piece; mesal side almost straight, lateral side widening to middle, somewhat abruptly narrowed for apical half (this parallel-sided and weakly acuminate at extreme apex); apex and mesal side clothed with moderately dense setae (those at apex longer and curved). Basal piece slightly transverse, laterally with narrow chitinized band extending towards apex of lateral lobe. Y-piece moderately long, stem longer than arms.

General pubescence. Reduced in male, more so in female. Dorsad. Fimbriate below inferior lobes of eyes, the setae encroaching on genae. Prothorax almost uniformly clothed with short, erect setae; midline of pronotum, and narrow parallel stripe to each side glabrous. Scutellum clothed with short, recumbent, dark setae; elytra glabrous. Ventrad. Prosternum almost glabrous, some punctures with very short seta; sides of metasternum, and metepisternum with suberect setae. In male with short, moderately dense, recumbent, grey pubescence across basal half of metasternum, becoming sparser on apical half, in female metasternum almost glabrous; in both sexes, metepisternum along sides of apex with narrow fascia of similar pubescence, but dense and pale ochreous in color. Abdomen: sides of urosternites I–IV (II–IV in female) with incrementally smaller narrow, white fascia; rest of abdomen with sparse, suberect, grey pubescence, becoming somewhat denser towards apex; in female surface almost glabrous. Antennae. Micropubescent from segment IV to apex; densely clothed with thick setae from scape to antennomere VI, in both sexes. Legs. Generally rather weakly clothed with semierect setae, denser on femoral claves and tibia of middle and hind legs, front leg lacking these setae. In both sexes, metatibia with dense setae on apical half, just long enough to be called a brush.

General puncturation. Similar in both sexes; exceptionally rugose, dense, alveolate, and sometimes beveled. Dorsad. Head with labrum and clypeus sparsely punctured in both sexes; adjacent area of frons with moderately large, deep, confluent, alveolate punctures lodged in a carinate matrix; vertex rugosely punctured, these small, alveolate, lodged in a matrix of micropunctures; mentum-submentum with small alveolate punctures scattered between six rows of weakly arced, transverse carinae. Pronotum not tuberculate; entirely rugosely punctate, these alveolate and mostly confluent in both sexes; in male pronotal disc occupied by a weakly raised, trident-shaped area of shallower, contiguous punctures lodged in a matrix of short transverse carinae; between prongs of trident, and towards sides of disc, carinae absent, punctures deeper and confluent; in female pronotal surface less differentiated, the trident-shaped area not raised and ill demarcated. Elytral puncturation similar in both sexes; generally alveolate; at base concentrated on humeri. On basal half of elytra lateral margins with various rows of mainly large punctures, towards apex reduced to double row of small ones; sutural margins at base of elytra with four rows of small, beveled punctures, diminishing to single row near middle of elytra, impunctate from middle to apex. Translucent panels squeezed into narrow area between punctures of lateral and sutural margins; panels almost impunctate, surface of basal third opaque yellow due to dense microsculpture. Ventrad. Middle of mesosternum with some large and small punctures lodged in matrix of rugose microsculpture; at sides smooth and sparsely punctate; mesepimera moderately densely punctate. Abdomen incrementally punctate from base to apex, punctures small to very small, shallow, simple or beveled; male with urosternites I—IV sparsely punctate towards midline, more densely towards sides, and urosternite V densely punctate in soleate depression, sparsely towards sides; female with urosternites I—V almost entirely sparsely punctate, hardly more so at sides.

Color. Not sexually dichromatic; body and appendages (including metatarsi) generally black; rostrum, pronotum, sides of pro- and mesothorax, antennal scape and femora may be suffused with rufous. Elytral apex not yellow. Metafemoral peduncles mostly yellow, base of metatibia yellow.

Diagnosis. The shortest diagnosis for this genus (with its long subulate elytra) could be the male’s strongly dentate antennomere XI, shared by both sexes of the genus Phygopoides (with its short cuneate elytra) and some species of Odontocroton (in which XI is weakly dentate); but there may be other Rhinotragini genera that share this character as it is easily overlooked.

Rhinobatesia may be separated from other genera of Rhinotragini by the following combination of characters. Inferior lobes of eyes well separated in both sexes. Pronotum without tubercles, surface rugose, with trident shaped callus occupying disc (poorly defined in female). Prothorax subcylindrical (male l/w 1.28), sides weakly rounded, widest near middle (male quotient 2.14); procoxal cavities plugged at sides, closed behind. Elytra subulate, widely fissate, 2.67–2.76× longer than wide. Antennae crassate, in male antennomere XI toothed (subserrate). In male hind margin of metasternum truncate (almost so in female). Legs robust. Abdominal process almost coplanar with abdomen in both sexes. Metafemoral clave shorter than peduncle. Metatarsomere I shorter than II+III.

Rhinobatesia may be separated from all species of Odontocera by the following character combination: width of one inferior lobe of eyes/interocular distance similar in both sexes, in male width lobe/ interocular 3.4, in female 2.0; elytra subulate, widely fissate, 2.67–2.76 longer than wide; antennae crassate, in male antennomere XI toothed (subserrate); antennal apex reaching metacoxae in male, middle of urosternite I in female; in male, hind margin of metasternum truncate (almost so in female); legs robust; abdominal process almost coplanar with abdomen in both sexes; metafemoral clave shorter than peduncle; metarsomere I shorter than II+III.

Rhinobatesia may be separated from O. fasciata by the following character combination: in Rhino- batesia rostrum elongate, width/length 1.6–1.7 (in O. fasciata short, width/length 2.5–2.7); in Rhinobatesia width of one inferior lobe of eyes/interocular distance in male 3.4, in female 2.0 (in O. fasciata width of lobe/interocular in male 4.3–4.5, in female 0.88); in Rhinobatesia superior lobes of eyes widely separated (in O. fasciata narrowly separated); in Rhinobatesia antennomere III 1.4–1.5 longer than scape, basal antennomeres with dense, thick setae on underside, XI dentate (in O. fasciata antennomere III 1.0–1.1× length of scape, basal antennomeres with sparser, thinner setae on underside, XI not dentate); in Rhi- nobatesia prosternum strongly declivous, prosternal process not laminate (in O. fasciata prosternum hardly declivous, prosternal process laminate); in Rhinobatesia elytra fissate and narrow for apical half, 2.7–2.8× longer than width across humeri, the latter not hiding mesepimerum (in O. fasciata elytra dehiscent and hardly narrowed for apical half, 3.1–3.3× longer than width across humeri, the latter hiding mesepimerum); in Rhinobatesia abdomen apiform in male, fusiform in female, abdominal process nearly flat in both sexes (in O. fasciata abdomen in both sexes vespiform and abdominal process near vertical); in Rhinobatesia mesofemur much longer than tibia, mesofemoral clave slightly longer than peduncle (in O. fasciata mesofemur slightly longer than tibia, mesofemoral clave much longer than peduncle); in Rhinobatesia metafemur strongly pedunculate-clavate, clave shorter than peduncle, metatarsomere I shorter than length of II+III (in O. fasciata metafemur subcylindrical, clave much longer than peduncle, metatarsomere I longer than length of II+III); general color black, pronotum without characteristic surface ornamentation (in O. fasciata general color yellow, pronotum with recumbent golden pubescence and transverse bands of different colors); tegmen strongly chitinized, lateral lobes slightly divergent and twisted (in O. fasciata tegmen weakly chitinized, lateral lobes parallel and straight).

Rhinobatesia is readily separated from Odontocroton by the following: Rhinobatesia rugicollis is a robust species, length body/width metasternum in male 5.2, in female 4.6 (species of Odontocroton are less robust, length body/width metasternum in male 5.4–8.3, in female 5.2–6.1); in Rhinobatesia rostrum long, width/length 1.6–1.7 (in Odontocroton rostrum shorter, width/length 2.1–2.5); in Rhinobatesia metatarsomere I short, lengths I/II+II = 0.7–0.9 (in Odontocroton I/II+III = 1.4–1.6). Rhinobatesia is a Mexican/Central American species (all species of Odontocroton are from South America).

Species included. Rhinobatesia is a monotypic genus established for Odontocera rugicollis Bates, 1880 , with O. nevermanni Fisher, 1930 as a new synonym.

Etymology. This Rhinotragini genus is named for Henry Walter Bates (1825–92), arguably the best of the nineteenth century’s cerambycid taxonomists. The genus is male.

Figures

Figures 31–36. Species of Odontocroton (Group B (ii)) and Rhinobatesia n. gen. 31–34. Odontocroton septemtuberculatus (Zajciw, 1963). 31) Male, dorsal aspect. 32) Male, ventral aspect. 33) Female, dorsal aspect. 34) Female, ventral aspect. 35–36. Rhinobatesia rugicollis (Bates, 1880). 35) Holotype male. 36) Female, holotype of junior synonym Odontocera nevermanni Fisher, 1930.

Figures 43–51. Genitalia (tegmen) of the genera Odontocera, Odontocroton and Rhinobatesia. 43) Odontocera fasciata. 44–46. Odontocroton (Group A). 44) Odontocroton flavicauda. 45) Odontocroton melzeri. 46) Odontocroton soror. 47–50. Odontocroton (Group B). 47) Odontocroton apicalis. 48) Odontocroton rufifrons. 49) Odontocroton quinquecallosus. 50) Odontocroton septemtuberculatus. 51) Rhinobatesia rugicollis.