Rhyncholampas

Souto, Camilla, Mooi, Rich, Martins, Luciana, Menegola, Carla & Marshall, Charles R., 2019, Homoplasy and extinction: the phylogeny of cassidulid echinoids (Echinodermata), Zoological Journal of the Linnean Society 187, pp. 622-660 : 628-629

Genus Rhyncholampas : This genus was described to include C. caribaearum and Rhyncholampas pacifica

( Agassiz, 1863), because the genus Cassidulus was thought to be preoccupied among the Mollusca. After analysing some fossil specimens, Agassiz (1872: 153, 342) synonymized Rhyncholampas with Rhynchopygus d’Orbigny, 1856 , although he was compelled to separate these genera in 1869 ( Agassiz, 1869: 270). Rhyncholampas is the sister taxon to Cassidulus ( Fig. 1), and some authors (e.g. Mortensen, 1948a) have considered them to be synonymous. Kier (1962: 18) mentioned that both genera include species with intermediate characteristics that make these

‘Species analysed’ are those species where we were able to examine specimens. Of those ‘species not analysed’, we made taxonomic calls based on the literature: ‘probably valid’ are species whose morphological description and/or images most closely fit the description of their assigned genus; ‘uncertain status’ refers to species for which we did not have access to the literature or that had descriptions and images too poor to allow for confident identification and thus they need further morphological analysis; and ‘misclassified’ are species whose description and/or images clearly indicate that they should be placed in a different genus. The percentage of the species in each cassidulid genus included in the phylogenetic analysis is given in the last column: lowest value = ‘species analysed’/(‘species analysed’ + ‘probably valid’ + ‘uncertain status’); largest value = ‘species analysed’/(‘species analysed’ + ‘probably valid’).

*Genus designations before the analyses. See section ‘Taxonomic assignment of cassiduloids analysed in this study’ for taxonomic assignments following the analyses performed here.

† Many of these described as Pygorhynchus Agassiz, 1839 .

difficult to allocate unequivocally to either genus, leading us to analyse all available species to test the monophyly of these genera. The following 18 species (one extant and 17 extinct) currently classified as Rhycholampas are included in the analyses: the type, Rl. pacifica , Rhyncholampas alabamensis (Twitchell in Clark & Twitchell, 1915), Rhyncholampas anceps Lambert, 1933 , Rhyncholampas ayresi Kier, 1963 , Rhyncholampas carolinensis (Twitchell in Clark & Twitchell, 1915), Rhyncholampas chipolana Oyen & Portell, 1996 , Rhyncholampas conradi (Conrad, 1850) , Rhyncholampas daradensis (M.Lambert in Meunier, 1906), Rhyncholampas ericsoni ( Fischer, 1951) , Rhyncholampas evergladensis ( Mansfield, 1932) , Rhyncholampas globosa ( Fischer, 1951) , Rhyncholampas gouldii (Bouvé, 1846) , Rhyncholampas grignonensis (Defrance, 1825) , Rhyncholampas mexicana ( Kew, 1920) , Rhyncholampas riveroi ( Sánchez Roig, 1949) , Rhyncholampas rodriguezi Lambert & Sánchez Roig in Sánchez Roig, 1926 (its type specimen could not be analysed but two morphotypes were observed, therefore both were included in the analyses: Rl. rodriguezi _A has an inflated rounded test and a short petal III, whereas Rl. rodriguezi _R has an oval test and a relatively long petal III), Rhyncholampas sabistonensis ( Kellum, 1926) and Rhyncholampas tuderi Lambert, 1937 . A few Rhyncholampas species had already been synonymized by Cooke (1959); for example, Rl. evergladensis with Rl. sabistonensis and Rl. alabamensis with Rl. gouldii (but see Osborn & Ciampaglio, 2014, for a revalidation of Rl.alabamensis ).