Description and biological notes of the larva of Cionus olivieri Rosenschoeld, 1838 (Coleoptera, Curculionidae), with a comparison with other species of the tribe Cionini

By

Jiang, Chunyan
Caldara, Roberto
Skuhrovec, Jiří
Zhang, Runzhi

Type

Article

Date of Publication

2020

Original Publication

ZooKeys

Volume

976

Pages

131--145

Subjects

biology;Curculioninae;ecology;immature stages;Verb , weevils

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.976.53930

 

Abstract

The mature larva ofCionus olivieriRosenschoeld, 1838 is described and illustrated in detail for the first time. It is compared with those known from the same genus and other genera in the tribe Cionini and with those of the hypothesized sister tribe Mecinini in the Curculioninae. The larvae ofCionushave three distinctive diagnostic features: the reduced number of setae on the epicranium (only two or threedesand one or twofs) and on the epipharyngeal lining (only twoals, twoams, and nomes); i.e., distinctly fewer than the most frequent number of setae in weevils, and mandibles dentate or angulate internally near the base. If considered together withStereonychusSuffrian, 1854, the other genus of Cionini with larvae studied in detail, it is preliminarily suggested that mature larvae of this tribe might be characterized by six main diagnostic features: (1) labial palpi one-segmented, (2) labral rods absent, (3) pedal areas swollen to form large lobes or prolegs, (4) mandible with sharp apical teeth, (5) reduced number offson frons, only one or twofs, and (6) reduced number of epipharyngeal setae (two or threealsand two or threeams, but nomes). It was noticed thatC. helleriReitter, 1904 from Japan, a very distinct species in the genus for some characters of the adult, also possesses distinctive characters in the larva which are uncommon among known cionines. New biological data onC. olivieriwith the discovery of its host plant,Verbascum songaricum(Scrophulariaceae), in central Asia are also reported.