 |
Clytus arietus
Classification
Diagnostic Features of Larvae
- Mature larva. Length up to 20 mm; maximum breadth (at prothorax) 5.5 mm. Head with maximum head-width 3.1 mm. Gena gradually narrowed up to mouthframe; smooth, and with a few long pale setae; temples rather narrowly ferruginous behind ocellus, and not as darkly pigmented as front margin of frons. Sclerotization of mouthframe not interrupted beneath antennae, ferruginous. Antenna with second segment twice as long as broad; third segment three times as long as broad, and just over half as long as second; supplementary process conical, tapering, nearly half as long as third segment. Mandible broad, with basal part ferruginous; apical part pitchy; longitudinal impression absent. Labrum transversely oval, fleshy, with rather long pale setae. One pair of ocelli present; lens large, convex; pigmented spot rather indistinct. Hypostoma with front margin broadly ferruginous and distinctly longitudinally striate; sutures ferruginous, curved. Gula distinctly raised; sutures concave, distinct and strongly divergent. Maxilla with lobe entirely glabrous on inner margin; maxillary palpi with third segment short, equal to second; dorsoexternal process of palpifer much shorter than third segment of palp. Labial palpi with second segment much broader than and as long as third. Prothorax with pronotum glabrous, longitudinally rugose (almost striate); median cleavage line distinctly impressed. Abdomen with ampullae very finely rugose, reticulate; median longitudinal furrow rather broad and deep. Pleural disc wrinkled, reticulate and rather indistinct. Legs absent.
Pupa. Length 7-15 mm; maximum breadth 4 mm. Head with vertex visible from above, smooth; front transversely striate medially, glabrous. Antennae extending as far as first (in female) or second (in male) abdominal segment where they terminate above elytra and wings. Eyes strongly convex, glabrous. Labrum triangular, glabrous. Pronotum slightly elongate, with sides moderately rounded and smooth: posterior half glabrous, or almost so; anterior half with numerous scattered, short, fine setae and a few (less than ten) conspicuous spines on each lateral region. Mesonotum smooth and glabrous or almost so. Metanotum similar; scutellar groove distinct. Elytra and wings extending to third abdominal segment. Abdomen with tergites one to six each with a broad, transverse band of short spines which are stoutest near posterior margin. Seventh tergite transverse, with sides converging posteriorly, and hind margin strongly rounded; bearing similar spines, but also a transverse row of from four to five very large spines (which are curved forward) near posterior margin. Eighth tergite slightly transverse, and posterior margin with from four to five slightly smaller spines which may be either directed posteriorly or recurved. Ninth segment retracted into eighth. Sternites sometimes glabrous, but usually with a few fine minute setae, especially near lateral regions. Pleura moderately protuberant, longitudinally rugose and glabrous. Legs with hind femora extending as far as sixth abdominal segment and lying parallel to longitudinal axis of body. Functional spiracles present on first five abdominal segments, but vestigial ones present on segments six to eight; peritreme rather broadly oval, with anterior half much thicker than posterior half and raised well above general level of cuticle; surrounded by a bulbous, cuticular protuberance. Adapted from Duffy (1953).
Biology and Economic Importance
- Members of this tribe are known from various host plant families and several genera (e.g., Chlorophorus, Xylotrechus) are considered economically important. Species of this tribe are potentially invasive outside their native range. More information is available at the CAPS website.
Selected References to Larvae Specimens
| |
