Chaeridiona picea Baly, 1869,

Świętojańska, Jolanta, Chorzępa, Magdalena & Ghate, Hemant, 2006, Description of last instar larva and pupa of Chaeridiona picea Baly, 1869 and Oncocephala quadrilobata (Guérin, 1844) (Coleoptera: Chrysomelidae: Cassidinae: Oncocephalini) from India, Zootaxa 1341, pp. 49-68: 51-59

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Chaeridiona picea Baly, 1869


Chaeridiona picea Baly, 1869 

( Figs 1View FIGURE 1, 2View FIGURE 2, 5–13View FIGURES 5 – 13, 21View FIGURES 21, 22, 23, 24View FIGURES 23 – 26, 27–30View FIGURES 27 – 30, 35View FIGURES 35, 36)

Mature larva

Measurements of body (n= 2): length (except head, from base of pronotum to end of body): 4.2, 4.4 mm; width across mesonotum: 1.5, 1.6 mm.

Body strongly flattened dorso­ventrally, elongated, widest across 4 th abdominal segment ( Figs 1View FIGURE 1, 2View FIGURE 2, 27, 28View FIGURES 27 – 30). Colour of alcohol preserved larva, on dorsal as well as ventral side, yellowish­brown ( Figs 27, 28View FIGURES 27 – 30).

Segments of thorax and of abdomen transverse. Lateral margin of pronotum broadly rounded. Mesonotum and metanotum slightly shorter and wider than pronotum. First abdominal segment more or less as wide as meso­ and metanotum, width reduced posteriorly. Posterior tip of body triangular.

Segments of thorax without lateral scoli. Abdominal segments 1–8 with one lateral scolus on each side. Scoli armed apically with one pointed seta. In the middle length of scoli, one (sometimes two) pointed seta placed dorsally and one ventrally ( Figs 1View FIGURE 1, 2View FIGURE 2).

Nine pairs of spiracles: one pair on mesonotum and eight on abdominal segments 1 to 8.

Dorsal and ventral side of body with short pointed setae and slightly shorter minute setae placed at anterior margin of segments. Meso­, matanotum and first 7 abdominal segments each has a transverse fold across the middle (plical area).

Pronotum with 15 pointed setae and two campaniform sensilla on each side. Two setae on each extreme lateral margin of pronotum. Anterior border of meso­ and metanotum with a pair of very minute setae medially and two minute setae on each side laterally. Abdominal segments with a pair of very minute setae medially and one minute seta on each side laterally. Moreover, meso­ and metanotum with two rows each of 6 setae placed posteriorly and a group of 4 setae on each side laterally. Dorsal side of 1–7 abdominal segments with two pairs of pointed setae close to anterior margin, two rows each of 3 setae close to posterior margin and 2 pointed setae on each side close to spiracle. The last abdominal segment different in shape than the remaining ones, with elongated spiracles placed very close to each other and forming triangular tip of body. The last segment with two pairs of setae close to anterior margin and two pairs in posterior part. Chaetotaxy of dorsal side of body as in Figure 1View FIGURE 1.

Pro­, meso­, and metasternum with two pairs of minute setae at anterior margin and four pointed setae in the middle. Two setae or one seta at the base of each coxa of the first pair of legs and one seta at the base of second and third. Abdominal segments 1–7 with a pair of minute setae at anterior border, 8–10 pointed setae in row in the middle and two setae on postero­lateral side. Last abdominal segment with a pair of minute setae at anterior border, six pointed setae in row close to anterior border and a pair of setae in posterior part of segment. Chaetotaxy of the ventral side of body as in Figure 2View FIGURE 2.

Head well sclerotized, prognathous, partially retracted into pronotum ( Figs 27, 28View FIGURES 27 – 30). Epicranial stem absent ( Figs 5, 6View FIGURES 5 – 13). Median endocarina well developed extending between frontal arms. Frontal arms V­shaped. Fronto­clypeal suture present, fine. Clypeus with a pair of setae and a pair of campaniform sensilla. Frons, on each side, with two short setae and one campaniform sensillum placed anteriorly; three short setae and two campaniform sensilla placed medially close to frontal arm; and laterally two short setae placed close to frontal arm. Vertex (epicranium) on each side with five short setae and one campaniform sensillum. On each side of head, close to stemmata, three longer pointed setae and one short seta and one campaniform sensillum. Temporal side with four campaniform sensilla and four setae: three long, and one slightly shorter than the first one.

Stemmata black, six on each side of head.

Antennae 3 ­ segmented. Basal segment transverse, distinctly wider than the remainder. Median segment stout, slightly shorter than wide. Third segment slightly longer than wide.

Labrum free, wider than long, with slightly emarginate anterior margin ( Figs 7, 8View FIGURES 5 – 13). Mid and anterior part of ventral surface (epipharyngeal area) with numerous stout spines, lateral parts with tiny spines;ventromedian part with a pair of pointed setae, two pairs of very small setae and two groups of a few sensilla (campaniform or peg like). Anterior margin with three stout long setae ventrally on each side. Dorsally, anterior margin with one stout seta that is shorter than the remaining setae in the middle of emargination, and with five stout long pointed setae on each side. Dorsal side of labrum with four setae and four campaniform sensilla.

Mandibles heavily sclerotized, 4 ­dentate ( Figs 9, 10View FIGURES 5 – 13). Teeth blunt at apex. Two setae and two campaniform sensilla on dorsal side.

Maxillae and labium connate ( Figs 11–13View FIGURES 5 – 13). Each stipes with two short pointed setae. Palpiger distinct, in basal part heavily sclerotised, with two setae and two campaniform sensilla ventrally, and numerous short and long spines dorsally. Maxillary palp twosegmented. First segment of maxillary palpi with one campaniform sensillum ventrally and long spinules dorsally. Second segment provided with a group of sensilla at apex, and with a campaniform sensillum below the apex. Galea fused with lacinia into mala. Mala bears one campaniform sensillum and 11 long setae. Ligula covered with spines, spines in the middle stouter than lateral ones. Labium without palpi. Prementum with three pairs of campaniform sensilla. Postmentum with three pairs of setae.

All legs stout, with similar chaetotaxy ( Fig. 21View FIGURES 21, 22), three segmented, built with: coxa, femur and tibiotarsus. Tibiotarsus apically with heavily sclerotized, short and curved, single and simple claw armed basally with a pointed seta. Two campaniform sensilla above claw. Tibiotarsus with 9 long pointed setae: a complex of 7 setae surrounding claw and two setae in dorso­medial part. Femur with 7 long setae and one short seta close to the base dorsally. Basally, on internal side, a group of 5 campaniform sensilla and one short pointed seta, and at the base, ventrally, one campaniform sensillum. Also basally, but on external side, two campaniform sensilla. Coxa with setae arranged in three groups: first with three setae, second with a pair of setae and third with one seta.

Body flattened dorso­ventrally, elongated oval, widest across fifth abdominal segment. Color of alcohol preserved pupa: yellow to yellowish­brown ( Figs 29, 30View FIGURES 27 – 30).

Prothorax with two distinct processes at anterior margin and two to three small processes on each lateral margin. Head invisible from dorsal view.

Meso­and metathorax without any lateral scoli.

Abdominal segments 1–5 with simple lateral scoli on each side. Segments 6–8 with one simple and one two­branched scolus on each side. The eighth segment additionally with three branched scolus at posterior border ( Figs 23, 24View FIGURES 23 – 26, 29, 30View FIGURES 27 – 30). Each scolus armed apically with one seta, simple scoli with one or two setae close to base.

Abdominal segments with a pair of spiracles. Spiracles of first four segments of similar diameter. Spiracles of segments 6–8 with slightly smaller diameter than that of the segments one to four. Spiracle of the 5 th segment most prominent, elongated, distinctly longer than lateral scoli ( Figs 23View FIGURES 23 – 26, 29View FIGURES 27 – 30).