Family Callianassidae Dana, 1852 Remarks. Ghost shrimps are usually strongly heterochelous. Only a few taxa have subequal chelipeds, such as eucalliacine genera Calliaxina Ngoc-Ho, 2003; and Eucalliax Manning & Felder, 1991. The chelipeds (P1) of callianassid shrimps are laterally flattened and are subject of intraspecific variation as well as sexual dimorphism (or even polymorphism) (e.g. Manning & Felder 1986; Felder & Lovett 1989; Schweitzer Hopkins & Feldmann 1997; Swen et al. 2001; Mourik et al. 2005; East 2006). Manning & Felder (1991) turned attention to the characters on chelipeds, although they discussed extant American taxa only. The taxonomic importance of the chelipeds in systematics of callianassid genera was emphasized also by Ngoc-Ho (2003) when comparing genera within the subfamily Eucalliacinae. Such studies are considered of great importance for palaeontologists working with incompletely preserved individuals.

Published as part of Hyžný, Matúš & Gašparič, Rok, 2014, Ghost shrimp Calliax de Saint Laurent, 1973 (Decapoda: Axiidea: Callianassidae) in the fossil record: systematics, palaeoecology and palaeobiogeography, pp. 37-57 in Zootaxa 3821 (1) on page 41, DOI: 10.11646/zootaxa.3821.1.3, http://zenodo.org/record/4919918