Peltochares, Regimbart, 1907

Minoshima, Yûsuke N., Fikáček, Martin & Liu, Hsing-Che, 2023, Larval morphology of Crephelochares and Peltochares (Coleoptera: Hydrophilidae), Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 63 (2), pp. 305-322 : 319-320

Identity of Peltochares larvae by BERTRAND (1962)

BERTRAND (1962) described some hydrophilid larvae collected in Madagascar as belonging to the genus Peltochares , based on the identity of the associated adults, which resembled Peltochares conspicuus by their flat and disc-like body. However, P. conspicuus or similar species of Peltochares have never been recorded from Madagascar, and the identification is therefore doubtful (GIRṒN &

SHORT 2021). The larvae of P. atropiceus described here do not correspond with those described by BERTRAND (1962)

and we hence consider the identification of the Malagasy larvae to be incorrect.

This fact raises the question of the identity of the larvae.

Judging from the description and figures by BERTRAND

(1962), we consider that the larvae belong to Tritonus

Mulsant, 1844, of the tribe Laccobiini . This is supported by the following evidence:

(1) Tritonus species are flat and disc-like in body shape and superficially similar to P. conspicuus ( SHORT 2008, FIKÁĆEK et al. 2017).

(2) Tritonus is distributed in Madagascar ( SHORT 2008).

(3) The specimens in BERTRAND (1962) were collected on wet rock surfaces, which is the habitat of Tritonus in Madagascar ( SHORT 2008, FIKÁĆEK et al. 2017).

(4) Many characters of the larvae described by BERTRAND (1962) correspond with Tritonus larvae described by FIKÁĆEK et al. (2017): the epistomal lobes are almost symmetrical; the nasale is slightly asymmetrical, with four teeth; the shape of the frontal and coronal lines is identical to that of Tritonus ; the mandibles are symmetrical and with three inner teeth; the pronotum is oval in shape; the metathorax has a pair of triangular dorsal plates; the legs are well-developed. BERTRAND (1962)

only did not mention the elongated spiracles, which were described in FIKÁĆEK et al. (2017).

The larval and adult morphology, habitat and distributional data of the ‘ Peltochares ’ larvae described by BERTRAND (1962) indicate that these larvae most likely belong to the genus Tritonus .