Chaetotaxic Characters Research Articles

The external morphology of the pseudoscorpion Roncus andreinii

The external morphology of the four postembryonic instars of Roncus andreinii (di Caporiacco, 1925) is described and compared with one of the related R. lubricus L. Koch, 1873 (Gabbutt & Vachon, 1967), with particular emphasis on disposition of the chelal trichobothria in relation to growth.From the evaluation of characters it is concluded that a few morphometric and chaetotaxic characters (i.e. the length, ratio and shape of pedipalpal articles, the ratio of fingers/pedipalpal hand, the chaetotaxy of sternites II and III) represent good specific discriminants, while the relative position of trichobothria along the chelal axis is nearly the same in both species.The localization of the growing and non‐growing regions along the pedipalpal fingers may be of practical use in the search for new taxonomic characters.

A Reclassification of the Dacini (Tephritidae-Diptera)1

As I have indicated in various publications on the Dacini, I cannot agree with the generic concepts which have been followed by most of the workers on this group. I prefer not to base genera upon secondary sexual characters, unless accompanied by ample supporting characters, preferably common to both sexes. I also prefer not to base genera upon single chaetotaxic characters, i. e., the presence or absence of certain bristles, in varying combinations, unless accompanied by supporting characters. In my detailed study of this group such variations and intergradations have been seen in the chaetotaxy that it is felt that these are not always reliable criteria.