Notodascillus Carter

Jin, Zhenyu, Ślipiński, Adam & Pang, Hong, 2013, A revision of the genus Notodascillus Carter (Coleoptera: Dascillidae), Zootaxa 3613 (3), pp. 245-256 : 246-251

Notodascillus Carter

Notodascillus Carter, 1935: 186 , Type species, original designation: Dascillus brevicornis Macleay, 1872 .

Diagnosis. The members of this genus are easily distinguished from all similar Australian beetles by a combination of their long and serrate antennae (Figs. 26–28), 5-segmented tarsi bearing divided membranous lobes, hind coxae with coxal plates, and large, exposed pro- and mesotrochantins (Figs. 20–22).

Notodascillus differs from Dascillus cervinus (Linnaeus) , the type species of Dascillus , in having a distinctly crenulate posterior margin of pronotum (Figs. 8, 11), a very long ovipositor (Fig. 29) and male genitalia with the phallobase of the tegmen about as long as or only slightly shorter than the parameres (Figs. 32–34, 39–41, 46–48). In D. cervinus the posterior pronotal margin is smooth, the ovipositor strongly reduced and without baculi, and the parameres distinctly longer than the basal piece of the aedeagus. The remainder of species currently placed in Dascillus and other genera exhibit a wide array of character states, but none have the combination given above for Notodascillus .

Description. Length 6–14 mm, females usually larger than males. Body elongate, about 2.4–2.9 times as long as wide, weakly convex; brown or dark brown, upper surfaces matt, densely clothed with short decumbent setae. Head ( Figs. 1–3 ) subquadrate, slightly declined. Eyes large, entire, finely facetted, moderately protuberant and transversely oval in cross-section. Antennal insertions exposed, widely separated, not borne on raised tubercles. Subantennal grooves absent. Frontoclypeal suture distinctly impressed, straight; clypeus short, truncate anteriorly. Gular sutures incomplete anteriorly, widely separated; corpotentorium laminate, broad, anterior arms narrowly separated at base, not expanded mesally. Cervical sclerites well-developed. Labrum visible, free, slightly transverse, trapezoidal; distinctly sclerotised and setose at base, membranous anteriorly.

Antenna (Figs. 26–28) 11-segmented, antennomeres serrate beginning on antennomere 3 (weakly serrate in female), in males reaching posteriorly to middle of elytra, in female usually shorter, reaching posterior margin of pronotum; scape robust, about 1.6–1.8 times as long as pedicel; terminal antennomere rounded at apex and distinctly longer than penultimate.

Mandible ( Fig. 6 ) short and broad, strongly and abruptly curved mesally, without deciduous apical cusps, unidentate apically, external surface setose; incisor edge with two or rarely single tooth; mola and prostheca absent. Maxillary ( Fig. 4 ) lobes well developed; apex of galea densely pubescent and bilobed; lacinia without hooks or teeth; apical maxillary palpomere fusiform or parallel-sided and truncate apically. Apical labial palpomere ( Fig. 5 ) fusiform; mentum trapezoidal, emarginate anteriorly; ligula membranous, deeply bilobed and longer than palpomere 1.

Prothorax (Figs. 8, 11) trapezoidal, transverse, about 0.5–0.7 times as long as wide; sides straight or weakly arcuate; lateral carinae complete, simple with narrow margin but without distinct bead; anterior angles obtuse, posterior angles blunt or weakly acute; posterior edge tri-emarginate and finely crenulate; disc moderately convex, coarsely and densely punctate.

Prosternum (Figs. 9, 12) in front of coxa as long as longitudinal mid-coxal diameter; prosternal process entirely separating procoxae, slightly elevated, very narrow and pointed apically. Notosternal suture complete. Procoxae strongly projecting below prosternum. Procoxal cavities strongly transverse, narrowly separated and broadly open externally and internally; protrochantin exposed.

Scutellar shield (Fig. 13) distinctly elevated, simple anteriorly, rounded posteriorly; densely setose.

Elytra taken together 1.8–2.4 times as long as wide and 3.8–5.2 times as long as pronotum; weakly convex, relatively straight and gradually narrowing in apical third; apices weakly prominent; lateral margins narrow with distinct bead, entirely visible from above; elytral punctures very fine, in 12 rows; scutellary striole absent; elytral intervals flat; alternate intervals often with denser setae forming whitish longitudinal lines; epipleuron complete.

Mesoventrite (Fig. 10) broad anteriorly, separated from mesepisterna by complete sutures; anterior edge medially on the same plane as metaventrite, forming triangular projection laterally bordered by declined and oblique procoxal rests. Mesoventral process very narrow and divided, extending at least to middle of mesocoxal cavity; meso-metaventral junction monocondylic. Mesocoxal cavities separated by 0.2–0.3 coxal diameter; open laterally, closed by mesepimeron. Mesocoxae not projecting, mesotrochantin exposed.

Metaventrite (Fig. 10) as long as wide, moderately convex; discrimen incomplete anteriorly; transverse, katepisternal suture complete; exposed portion of metanepisternum long and broad; metepimeron exposed. Metacoxae contiguous, extending laterally to meet elytra; metacoxal plates well developed.

Hind wing ( Fig. 7 ) about 2.0–2.4 times as long as wide; radial cell 1.8–2.2 times as long as wide, not forming equilateral triangle, pigmented, inner posterior angle right or obtuse; cross-vein r3 very short and longitudinally oriented; apical field about 0.20–0.35 times total wing length with pigment patches around apical folds and r4, plus RP vein remnants; medial field with five free veins and MP3 often detached at base; wedge cell well-developed, apically acute; anal lobe well-developed, anal notch absent; AP divided, with posterior branch meeting basal wing margin.

Legs (Figs. 20–22) slender, similar in shape, covered with setae; femur elongate and linear, about as long as tibia in fore- and mid-legs while obviously shorter than tibia in hind legs; tibia with external dorsal side spinose; spurs paired, serrate. Tarsi 5-5- 5 in both sexes; membranous ventral lobes present on tarsomeres 1–4, at least distal 3 divided; claws simple; empodium absent.

Abdomen (Figs. 14–19) with five ventrites, ventrites 1 and 2 of similar lengths, connate; ventrites uniformly, densely pubescent with glabrous spots on each side; apex of ventrite 5 apex sexually dimorphic, prominent and narrowing apically in males (Figs. 14, 16, 18), rounded or truncate in females (Figs. 15, 17, 19); intercoxal process very narrow.

Sternite IX (Figs. 35, 42, 49) apically rounded and emarginate at base as well as bearing uniformly short setae in middle and apical part; posterior edge of tergite IX straight or obtuse; tergite X distinctly longer than tergite IX; apex of tergite X broadly rounded (Figs. 36, 43, 50).

Male genitalia (Figs. 32–34, 39–41, 46–48) trilobate, symmetrical; phallobase without struts, with median endocarina and base almost in a straight line; parameres articulated, more or less the same length as phallobase, apices somewhat rounded, apical third with sparse hairs and not upturned in inner margin of apical part. Penis with longer dorsal and shorter ventral lobes, ventral lobe slender and obtuse at apex; anterior edge of penis with short paired struts.

FIGURES 8–22. Notodascillus species: (8–10, 13, 14–15, 20–22) N. brevicornis (Macleay) ; (11–12, 16–17) Notodascillus sublineatus Carter ; (18–19) Notodascillus iviei sp. n. (8, 11) prothorax; (9, 12) prosternum; (10) meso–metathorax; (13) scutellum; (14, 16, 18) abdomen of male; (15, 17, 19) abdomen of female; (20) fore leg; (21) mid leg; (22) hind leg.

FIGURES 23–36. Notodascillus species: (23, 26, 29–36) N. brevicornis (Macleay) ; (25, 27) N. sublineatus Carter ; (24, 28) N. iviei sp. n. (23–25) male abdominal ventrite 5, lateral view; (26–28) antennae; (29) ovipositor; (30) body of female dorsal view; (31) body of male dorsal view; (32) aedeagus ventral view; (33) aedeagus dorsal view; (34) aedeagus lateral view; (35) sternite IX; (36) tergite X–XI.

Ovipositor (Fig. 29) very long and slender, lightly sclerotized except for baculi, paraprocts about 3 times as long as gonocoxites, which are undivided with longitudinal baculi slightly oblique at base; gonostyli welldeveloped and terminal.

Figures

FIGURES 1 – 7. Notodascillus brevicornis (Macleay). (1) head, dorsal; (2) head, ventral; (3) head, lateral; (4) maxillae; (5) labium; (6) mandibles; (7) hind wing.