Many, mostly older, names of animal species are nomenclaturally problematic, either because their orthography is unstable, orthey cannot be linked reliably to a taxonomic identity, due to the lack of recognisable descriptions and/or types. Yet, they repre-sent available (sensu International Code of Zoological Nomenclature) names and must be taken into account in zoologicalworks. This situation, with available senior, yet dubious names confounding nomenclature, is undesirable. It creates uncertain-ties at a time when molecular approaches are revolutionizing our concepts of species diversity, and fails us when the currentextinction crisis calls for efficient, accurate, and constructive approaches to document, monitor, and conserve biodiversity.The International Code of Zoological Nomenclature (The Code) provides a means to address this issue by restricting avail-ability, application and orthography of names to those included in the List of Available Names in Zoology (LAN). The Code(Art. 79) allows an international body of zoologists in consultation with the Commission to propose a candidate part of theLAN for a major taxonomic field. We explore this possibility for 3570 species-group names of Phylum Rotifera (of which 665are problematic), by presenting such a candidate Rotifera part of the LAN. The web site of the International Commission onZoological Nomenclature (http://www.iczn.org) will hold both the candidate list and a forum to facilitate consultation on thecandidate list, while the list itself also can already be freely downloaded from three other Internet sites: http://fada.biodiver-sity.be, http://rotifer.ansp.org/LAN, and www.hausdernatur.at/rotifera. We give here an overview of the general approach andprocedures applied in preparation of the candidate list, and anticipate that our effort will promote the process as well as result in a standard list of names for use in taxonomy, the Global Names Architecture and other biodiversity information initiatives.

Feeding rates of the gynogenetic Amazon molly Poecilia formosa and one of its sexual hosts, the sailfin molly Poecilia latipinna, were measured under winter and summer temperature conditions. Food consumption of the unisexual P. formosa in winter conditions was significantly higher than that of P. latipinna, and it is hypothesized that the resulting food stress might have an important influence on the population composition of these closely related fishes via higher winter mortality in P. formosa.

No abstract

This study reports significant differences between the gynogenetic Amazon molly Poecilia formosa and one of its sperm hosts, and the sexual sailfin molly Poecilia latipinna in the critical temperatures at which individual fishes lost motion control. Based on these measurements, it is suggested that cold snaps occurring in winter, but not summer temperatures, can significantly change population composition of these closely related fishes by inflicting higher mortality on P. formosa.