FNZ 29 - Cryptorhynchinae (Insecta: Coleoptera: Curculionidae) - Introduction
Lyal, CHC 1993. Cryptorhynchinae (Insecta: Coleoptera: Curculionidae). Fauna of New Zealand 29, 308 pages.
(
ISSN 0111-5383 (print),
;
no.
29.
ISBN 0-478-04518-2 (print),
).
Published 02 Dec 1993
ZooBank: http://zoobank.org/References/2F7DD8E6-5893-4E73-8E4B-A0D965EBE87E
INTRODUCTION
The Cryptorhynchinae are one of the largest subfamilies of the beetle family Curculionidae (true weevils), in the superfamily Curculionoidea. Members of this superfamily may be distinguished from most other beetles by the elongate rostrum formed by the front of the head (Fig. 45), although this is sometimes secondarily reduced (Fig. 6). Curculionidae, in addition to the rostrum, may be recognised by the form of the antennae, in which the terminal three segments are fused into a club and the second segment arises subapically on the first (Fig. 48) ('geniculate' antennae), and the small palpi, which are often concealed. The distinguishing features that enable identification of members of the Cryptorhynchinae are a prosternal canal and mesosternal receptacle (Fig. 46) into which the rostrum can fit (see 'Morphology and Terminology' section) and the presence of an uncus on the tibia (Fig.168). Unfortunately the sternal canal is not an infallible indicator of Cryptorhynchinae since some Zygopinae and Baridinae, for example, also have a canal yet some tribes within the Cryptorhynchinae lack it. While the canal does not occur in any other New Zealand weevil group, some native Cryptorhynchinae have the prosternal canal reduced and the mesosternal receptacle absent (Fig. 115); these beetles belong to the tribe Psepholacini, which is discussed in detail below.
All Cryptorhynchinae, apart from some Australian species which feed on herbivore dung and a Central American species which will eat psyllid larvae (Hansen et al., in prep.), feed on live or dead plant material. The majority of the New Zealand species for which rearing records are available (see Appendix 2) feed on, or at least in, dead wood; others feed in living wood or on other dead plant tissue, or mine green leaves. Feeding habits are discussed further in the section on biology, below.
The bulk of taxonomic work on New Zealand Cryptorhynchinae, as with other groups of beetles in this country, was done by Captain Thomas Broun at the end of the last century and the beginning of this. He is responsible for the vast majority of species descriptions and, through his correspondence with the European coleopterists Sharp and Pascoe, for the provision of specimens named by these authors. He also described 18 of the 42 genera accepted in this study (10 of which are new), and a further 12 genera which have been or must be sunk as synonyms of others. Unfortunately he did not provide keys to separate either species or genera, nor did he illustrate his species. It is clear from his descriptions that his generic concepts changed over time, and he did not always examine his collection when naming new 'distinctive' species. Further, nearly half the described species were placed in the large cosmopolitan genus Acalles; careful examination has revealed that in fact no New Zealand species belong to this genus. The final difficulty faced by anyone wishing to work on New Zealand Cryptorhynchinae follows the transfer of Broun's collection to the Natural History Museum formerly British Museum (Natural History) in London, thus removing the vast majority of the type specimens from New Zealand.
Broun gave each of his spccies a number, and sometimes used these rather than names to refer to taxa. A list of all numbers applied to Cryptorhynchinae is given in Appendix 3.
This study assesses the generic classification of New Zealand Cryptorhynchinae and provides a key to their identification to at least genus level. In addition to generic treatments the locations of all types are given and distributional and biological data for all species are summarised.