Definition of the number of instars, description of the second instar andredescription of the last instar and pupa of Pantophthalmus kerteszianus(Enderlein, 1914) (Diptera: Pantophthalmidae)

Abstract

The total number of larval instars of Pantophthalmus kerteszianus was determined through morphological and biometric studies. The second larval instar of P. kerteszianus is described, the last larval instar in detail and the pupa are redescribed. Larvae were collected from paricá trees (Schizolobium parahyba var. amazonicum) in the Paragominas county, Pará, Brazil. Upon collection, larvae and pupae were killed in boiling water, preserved in 70% alcohol, identified, measured and morphologically studied. The total number of larval instars was determined by techniques based on Dyar’s rule (1890), supported by measurements of the several characters: body length, maximum body width, maximum diameter of the prothoracic spiracle, maximum diameter of the anal spiracle, distance from the margin of the prothoracic spiracle to the lower bristle, distance from the margin of the prothoracic spiracle to the prothoracic margin, width of the median band of the prothorax and distance between the anal spiracles. Through these measurements it was possible to establish that P. kerteszianus has seven larval instars; this species is, up to now, the only one having the number of its larval instars determined. Photographs and drawings of the complete larvae and pupae, as well as of the most important structures discussed in the descriptions, are provided.