Panchaetothripinae, Bagnall, 1912

Lima, Élison Fabrício B., O’Donnell, Cheryle A., Sousa, Yago Lucas C. & Zamar, María Inés, 2021, Identification of second instar larvae of Panchaetothripinae (Thysanoptera Thripidae) in Brazil and Argentina, Zootaxa 5047 (4), pp. 453-464 : 454

Panchaetothripinae second instar larvae

Body usually clear and weakly sclerotized. Antennal segments usually light brown, except for apex of segment II and sub-basal band on segment III pale. Antennae 7-segmented, no surface microtrichia, segment IV more than three times longer than V, segment V with simple sense cone, segment VII usually elongate, 7–10 times longer than wide. Head with five pairs of setae, setae D3 usually acute and D5 always acute. Pronotum and mesonotum with seven pairs of setae. Metanotum with five pairs of setae. Spiracles present laterally on mesonotum and abdominal tergite VIII (sometimes also on tergite II). Abdominal tergites with three pairs of setae, tergite X usually parallelsided and with three pairs of anal setae ( Retithrips syriacus with 16–18 setae). Abdominal sternites IV–VIII with three pairs of setae, sternite IX with two (female) or three (male) pairs of setae. Dorsal setae with apex variably shaped, ventral setae with acute apex.

Larvae of Panchaetothripinae differ from other Thripidae especially by the usually elongated antennal segment VII, segment IV distinct from segment V, segment V longer than wide and abdominal segment X usually more or less parallel-sided. Additional characters on family-level are available in Speyer & Parr (1941), Heming (1991) and Vierbergen et al. (2010). In addition, the two larval stages are distinguished by differences in the pattern of chaeto- taxy: larva I lacks cephalic setae D5, pronotals D6, mesonotals D2, D3 and D5, metanotals D2 and abdominals D2 and D3 ( Heming, 1991). In general, there is some structural similarity between the same stages of larvae of different species, but the main characters used to distinguish the first larval stage of different species are not always applicable to larva II and vice versa ( Speyer & Parr, 1941).