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Dichostates quadripunctatus
Classification
Diagnostic Features of Larvae
- Mature larva. Length up to 17 mm; maximum breadth (at prothorax) 4.6 mm. Head strongly elongate, moderately depressed, widest at anterior third (maximum head-width 2.1 mm), sides abruptly though rather feebly constricted at middle, slightly converging posteriorly; frontal sutures indistinct; antennal foramen open behind; mouthframe moderately sclerotized, pale ferruginous. Frons broadly ferruginous antero-laterally and distinctly longitudinally striate, with eight setiferous pores; six epistomal setae present. One pair of ocelli present; lens round, convex; pigmented spot distinct. Hypostoma flat, testaceous; sutures distinct, ferruginous, slightly incurved; gular region with a very pale median cleavage line on each side of which is a pair of stout setae. Antenna 2-segmented; segment 2 quadrate and bearing a small, conical, hyaline process. Maxilla with palpal segment 3 elongate, slightly shorter than segment 2. Labial palpi with segment 2 cylindrical, slightly more than half length of segment 1. Mentum distinct from submentum. Prothorax with pronotum pale testaceous, sparsely setose anteriorly, glabrous and feebly rugose posteriorly. Prosternum with eusternum distinct, triangular and sparsely setose. Abdomen with each dorsal ampulla with a pair of rather indistinct transverse furrows and three rows of feebly defined moniliform tubercles. The anterior and posterior margins1 of all segments from the mesothorax to abdominal segment 7 broadly sinuate paramedially, the extreme margins microscopically spiculate. Tergite 9 bearing medially near posterior margin a pair of short, blunt urogomphi. Epipleurum protuberant on all segments. Pleural tubercles small, bearing about five setae; sclerotized pits absent. Legs absent. Spiracles with peritreme broadly oval.
Pupa. Length up to 11 mm; maximum breadth 4.5 mm. Head with vertex entirely visible from above, rather shallowly excavate and bearing two stout spines between antenna} bases. Front with several stout spines (each with a basal seta) arranged more or less in two widely separated, longitudinal rows; clypeus with transverse impression at base and bearing four to six short spines. Antennae extending as far as abdominal segment 3, where they are strongly curved ventrally to terminate near front coxae. Eyes flat. Mandibles each with a pair of short spines (each with a basal seta) near middle of outer face; labrum transverse with front margin broadly rounded; rather strongly protuberant and densely setose along front margin and base. Pronotum smooth; front margin bearing numerous short spines (each with a basal seta); disc almost devoid of spines. Mesonotum and metanotum each with a few scattered minute spines; scutellar groove indistinct. Elytra and wings extending to abdominal segment 4. Abdomen micro-granulate with tergites 1-6 each with several stout, curved, testaceous spines (each with a basal seta) which are arranged in more or less two transverse rows. Tergite 7 with spines stouter and ferruginous. Tergite 8 transverse with a median oval tubercle bearing two divergent, very stout spines and on each side two to four pairs of smaller spines. Tergite 9 roundly truncate posteriorly, the caudal area bun-shaped, finely longitudinally striate and with a deep median longitudinal cleft and a pair of minute, blunt, sclerotized processes (urogomphi?). Sternites glabrous. Pleura moderately protuberant, bearing two to five small spines. Legs with femora bearing a transverse row of short spines subapically; hind femora extending to abdominal segment 4. Functional spiracles present on segments 1-6; peritreme very thin, pale, reniform and scarcely raised above general level of -cuticle. Adapted from Duffy (1957). 1
Biology and Economic Importance
- Biology unknown for members of this tribe. Species of this tribe are potentially invasive outside their native range.
Selected References to Larvae Specimens
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