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MORPHOLOGY OF ADULT BEETLES A B sensory antennal areas clypeus lateral carina foramen C D frontoclypeal labrum suture trochantin labrum E F G lateral carina Figure 11. Adult morphology A,B Storeyandra frenchi C,D Arhopalus rusticus E–G Eurynassa sp. (Prioninae), (Parandrinae), head and (Spondylidinae), head and head and prothorax: prothorax: prothorax: E ventral A lateral C lateral F lateral B dorsal D dorsal G dorsal 9 AUSTRALIAN LONGHORN BEETLES Th e prosternal process between procoxae is always complete and extremely variable, also providing useful characters for the generic classifi cation. It is usually fl at but often arcuate or angulate and abruptly bent beyond the procoxae. In some Lamiinae, the prosternal process extends well beyond the procoxae (Fig. 156E) and articulates with a projection or a pit on the mesoventrite or is received in a deep fossa (e.g. Trigonoptera). Some genera of Cerambycinae and Lamiinae (e.g. Sybra) have an accessory mesal articulation developed as a knob on the prosternal process that fi ts into a procoxal fossa (Fig. 181B). Th e notosternal sutures are usually short and incomplete anteriorly but complete in some Prioninae. Th e procoxae are usually fl at and weakly to strongly transverse in Parandrinae, Prioninae and Spondylidinae (Fig. 11A,C,E) but are usually oval and project well below the prosternum in many Cerambycinae and Lamiinae. Th e protrochantin (Figs 11C, 164G) is exposed in all Parandrinae, Prioninae and Spondylidinae, but is sometimes concealed in Lamiinae (e.g. Stenellipsis, Fig. 178G) and Cerambycinae (e.g. Skeletodes). Th e procoxal cavities are variable but usually transverse and narrowly separated medially, with lateral extensions exposing the trochantins. Th e prosternal process is often expanded beyond the coxae and forms a narrow external closure by meeting narrow postcoxal projections in most Lamiinae (except Batocerini) but it does not form this external closure in most Prioninae and Cerambycinae. Th e internal closure (Fig. 45G) is usually broad and complete but it is absent in Parandrinae and Prioninae. Pterothorax Th e scutellar shield is almost always visible and not abruptly elevated (not visible in some wingless Lamiinae), anteriorly simple or separated from the mesoscutum by a transverse impression (Fig. 175G); in some genera of Tmesisternini (e.g Tmesisternus) the scutellum is large, projecting and anteriorly overlapping the posterior edge of pronotum (Fig. 155C). A stridulatory fi le is usually present on the mesoscutum, but always absent in Parandrinae and Prioninae; it is divided by a median mesoscutal carina in Arhopalus (Spondylidinae) and is nearly always complete in Cerambycinae and Lamiinae (strongly reduced or absent in some genera, e.g. Rhytiphora). Th e elytra are very variable in Cerambycidae but are usually much longer than wide and longer than the pronotum, often covering the entire abdomen, and are apically rounded, spinose or truncate. Substantial variation in elytra occurs in wasp- mimicking Cerambycinae with their elytra often short and truncate (e.g. Hesthesis) or apically narrowed (e.g. Enchoptera, Macrones), exposing several abdominal tergites (Figs 34A, 35A,B). Th e dorsal surfaces of the elytra are often polished and variably punctate with a leathery appearance in most Prioninae and Parandrinae, to coarsely, and sometimes serially punctate in various Lamiinae and Cerambycinae. Elytral intervals sometimes form elongate tubercles, ridges, costae or a reticulate network. Th e elytral epipleuron is usually vertical or oblique and incomplete apically (the fl at, complete epipleura in Phyxium are a notable exception, Fig. 113E). Th e epipleura are deeply emarginate at the level of the humeral tubercle, in fl ight exposing the wing bases in Tragocerus (Fig. 37G) and related taxa of Tragocerini that fl y without opening the elytra. Th e mesoventrite is large and almost always separated from the mesanepisterna by complete sutures; the anterior edge is sometimes on a lower plane than the metaventrite and usually has a median depression and paired procoxal rests laterally. Th e mesocoxae are usually circular, fl at and only exceptionally conical and projecting (e.g. cerambycines Macrones, Enchoptera). Th e mesotrochantin is usually large and exposed in Parandrinae, Prioninae and Spondylidinae, smaller and rarely concealed in 10 MORPHOLOGY OF ADULT BEETLES A B gland opening and dispenser C F D G E Figure 12. Adult morphology: A,B,D–G, Cerambycinae; C, Spondylidinae A Tricheops ephippiger, D Distichocera sp., F–G Australodon nearnsi head and prothorax, lateral male antenna Escalona & Ślipiński, B Stenoderus sp., head, lateral E Rhinophthalmus sp., male head: C Arhopalus rusticus, antenna head, ventral F lateral G frontal 11 AUSTRALIAN LONGHORN BEETLES Lamiinae and Cerambycinae. Th e mesocoxal cavities are narrowly to widely separated, circular to strongly transverse and usually laterally open to the mesepimeron (Fig. 10A) but closed by meeting of meso- and metaventrites in some Cerambycinae and a few Lamiinae (e.g. some species of Mesolita). Th e mesometaventral junction is usually simple in Prioninae and often has a metaventral knob in Parandrinae, many Lamiinae and Cerambycinae. In several Lamiinae and Cerambycinae, the mesocoxae have an accessory mesal articulation developed either as mesocoxal knob and a metaventral fossa or a metaventral knob fi tting into a mesocoxal fossa (Fig. 177D). Th e metaventrite is usually about twice as long as the mesoventrite (distinctly shorter in wingless species, e.g. Athemistus, Somatidia, Fig. 167F) with a moderately long discrimen and no postcoxal lines (Fig. 10A). Th e exposed portion of the metanepisternum is usually short and broad but may be very long and narrow or, rarely, not exposed (e.g. Mesolita). A triangular intercoxal process of the fi rst abdominal ventrite usually narrowly separates metacoxae that are fl at and without coxal plates. In some wingless species the metacoxae are less transverse and broadly separated medially (e.g. Somatidia). Th e metendosternite is very variable in Cerambycidae (Fig. 14D,E) but usually has moderately developed lateral arms, short laminae (absent in Prioninae and Parandrinae), no anterior process and the anterior tendons are close together or widely separated. Th e hind wings are usually well developed (Fig. 9C) but brachyptery and winglessness are not uncommon in many unrelated groups, particularly in Lamiinae. A rare case of sexual dimorphism occurs in Storeyandra frenchi (Parandrinae) with fl ightless males and winged females. Th e apical fi eld of the wing is long and usually has two sclerotised veins (RA4 and RP3+4), a dark sclerite apical to the radial cell and a subtriangular sclerite crossing r4. Th e radial cell is usually well developed and more or less elongate (Fig. 13A) but is sometimes short and incomplete. Th e medial fi eld usually has 4 or 5 free veins (sometimes 3 or rarely fewer) and never has a medial fl eck or binding patch. Th e wedge cell is well developed in almost all Prioninae (Fig. 9C) but absent in other subfamilies (Fig. 13A). All three pairs of legs are usually similar but in males of several Lamiinae the front legs are longer and sometimes with arcuate and internally toothed protibiae (Fig. 63H). Th e trochanterofemoral joint is mostly oblique, occasionally transverse (e.g. Batocera) to strongly oblique with the base of the femur abutting coxa. Femora are highly variable, usually widest at middle but in many Lamiinae and Cerambycinae are abruptly widened apically and clavate (Fig. 152D). Th e tibiae are usually weakly expanded apically and setose, but in Parandrinae and some Prioninae are strongly widened and often toothed at the apex and dentate along the outer edge. Th e tibial spurs are usually 2-2-2, rarely reduced to a single spur or absent on some pairs of legs. Antennal cleaning organs (antenna cleaners) are well developed only in Lamiinae as an oblique band of dense setae within a pubescent groove on the protibia and a similar setose structure on the outer face of the mesotibia (Fig. 30H–J). Th e mesotibial antenna cleaner has been a matter of controversy and in the “classical” cerambycid literature is regarded as present only if there is a distinct sulcus on the outer face of the mesotibia. However, the antenna cleaner is always present on the mesotibia in Lamiinae but its form varies from a dense row of setae along the outer edge (here termed a comb-like antenna cleaner, Fig. 30J) to a variously formed sulcus lined with dense setae (here termed a sulcate antenna cleaner, Fig. 30H,I). To clean the antenna, the beetle uses its front leg to grasp the antenna from above, draws it back and presses it against the outer face of the mesotibia with the antenna cleaner and then pulls out the antenna from between the tibiae, thus cleaning its surface and hairs. Tarsi are almost always 5-5-5 in both sexes and usually pseudotetramerous with a highly reduced penultimate 12 MORPHOLOGY OF ADULT BEETLES A AA MP RP 3+4 1+2 RP 1 Cu MP 3+4 AA MP 3 4 CuA MP AA 4 3 2 B C Figure 13. Adult morphology: hind wings Abbreviations A Arhopalus rusticus (Spondylidinae) AA anal anterior vein B Rhytiphora pardalis (Lamiinae) Cu cubital vein C Eroschema poweri (Cerambycinae) CuA cubitus anterior vein MP medial posterior vein RP radius posterior vein 13 AUSTRALIAN LONGHORN BEETLES tarsomere that is partly concealed at the base of the ventral lobe on the antepenultimate tarsomere. Th e fi rst three or at least tarsomeres 2 and 3 are widened and bear a dense pilosity on the underside. In some Lamiinae (e.g. Gnoma, Acalolepta, Momisis) tarsi are truly 4-segmented with the reduced penultimate tarsomere fused with the terminal one. In Parandrinae the penultimate tarsomere is relatively large and the tarsal lobes absent. Th e pretarsal claws are usually simple and narrowly to strongly divergent (termed divaricate) and rarely appendiculate (in some Lamiinae, e.g.

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