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Rhagium bifasciatum
Classification
Diagnostic Features of Larvae
- Mature larva. Length up to 34 mm; breadth (at prothorax) 7 mm. Form rather strongly depressed, but robust and parallel-sided. Head slightly wider than prothorax, strongly depressed, strongly transverse (maximum head-width 6.1 mm), with sides very strongly rounded; testaceous, shining, rather strongly sclerotized and sparsely covered with fine setae. Genae ferruginous, slightly rugose, keeled anteriorly and with a few moderately Jong setae. Mouthframe strongly sclerotized, smooth, ferruginous. Frons divided by a distinct transverse line (which is complete and widened medially) into an anterior ferruginous and a posterior testaceous area; two paramedian, shallow depressions present; front margin straight and fused medially into clypeus; at least ten epistomal setae present. Antenna very small, apparently two-segmented; second segment bearing a stoutly conical, hyaline process. Mandible (viewed laterally) very slender, about three times as long as basal width; pitchy and strongly shining; deeply notched and widened apically with a distinct tooth behind proximal angle of emargination. Labrum transversely oval, testaceous, with fine dense setae. One pair of large ocelli present, but pigmented spot indistinct. Gular sutures indiscernible; ventral, white cleavage line present. Maxilla well extended, movable; palpus very slender, last segment acutely attenuated, shorter than first or second; lobe slender, cylindrical. Prothorax depressed, at least twice as broad as long; dorsally sclerotized, testaceous, and with a pale, ferruginous, transverse band near front margin; lateral grooves and median cleavage line absent, so that pronotum is undefined; anterior half entirely smooth, and with a transverse row of short setae; posterior half slightly rugose, and with a transverse row of setae near hind margin. Eusternum triangular, smooth, shining, and with a few scattered setae. A1esonotum and metanotum dull, finely spiculate, and with several scattered setae. Abdomen depressed, with dorsal and ventral ampullae on segments one to seven; each dorsal ampulla with a well-marked median furrow, strongly tuberculate, and moderately shining. Pleural tubercle conspicuous, elongate-oval, smooth and bearing five setae; pleural discs undefined. Eighth and ninth terga smooth, sparsely setose, the latter broad, rather strongly sclerotized and bearing a conspicuous caudal spine (often blunt), the angle between the sides of support of the spine being about 100°. Tenth segment trilobed, each lobe protuberant, smooth and bearing a few short setae. Legs well developed, longer than maxillary palpi, slender, testaceous; unguiculus feebly sclerotized, attenuated; femur and tibiotarsus each bearing a few long setae. Spiracles with peritreme orbicular, moderately thick and sclerotized, pale testaceous, and slightly raised above general level of cuticle. First-instar larva. Length up to t ยท6 mm. Head with five pairs of ocelli, each with a conspicuous black pigmented spot. Front margin of frons ferruginous and with proportionately longer epistomal setae. Mesothorax, metathorax and abdominal segments one to eight with dorso-lateral egg-bursting spines; form short, bluntly triangular; pale testaceous. Ninth abdominal segment with terminal spine absent. Legs with unguiculus slightly curved. Spiracles biforous as in Rhagium mordax.
Pupa. Length 14-21 mm; maximum breadth 7.75 mm. Head strongly elongate, triangular, rugose; vertex with at least six long stout setae above each eye; frons with three to six stout setae near base of each antenna; base of clypeus with about six stout setae on each side. Antennae extending as far as first abdominal segment, where they are curved downward to terminate near base of each elytron. Mandible with a conspicuous dorso-lateral seta. Labrum transverse, rectangular, glabrous. Pronotum quadrate, with front margin strongly rounded and with a pair of large lateral tubercles; a row of erect, closely set, long, slender setae present along front and hind margins and scattered finer setae present on lateral tubercles and disc. Mesonotum with two groups of fine, ferruginous setae and scutellum with similar setae, especially near base. Metanotum with a group of similar setae on each side of scutellar groove, which is shallow and transversely striate. Elytra and wings extending to third abdominal segment. Abdomen with tergites one to six each bearing a pair of transverse rows of short ferruginous spines (each with a long basal seta). Seventh and eighth tergites with a row of similar but stouter spines along posterior margin. Ninth tergite with a transverse row of smaller spines and terminating in a long, stout, ferruginous spine which is directed downward. Sternites with sublateral groups of long, stout setae, except the ninth, which has only two setae, and the tenth, which is glabrous. Legs with numerous long, stout setae at apex of each femur, and paired setae near apex of each tarsus; hind femora extending to fourth abdominal segment. Functional spiracles present on first five abdominal segments, the sixth and seventh pairs being closed and vestigial; peritreme broadly oval, rather thin and level with general surface of cuticle. Adapted from Duffy (1953).
Biology and Economic Importance
- Biology and economic importance for this taxon coming soon.
Selected References to Larvae Specimens
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