Prioniodus Pander, 1856

Zhen, Yong Yi, Percival, Ian G. & Webby, Barry D., 2003, Early Ordovician Conodonts from Far Western New South Wales, Australia, Records of the Australian Museum 55 (2), pp. 169-220 : 203

Prioniodus Pander, 1856

Type species. Prioniodus elegans Pander, 1856 .

Remarks. Generic concepts and the apparatus compositions of Prioniodus and Baltoniodus Lindström, 1971 have long been debated. Fåhraeus & Nowlan (1978), and Cooper (1981) regarded the two as separate genera, based mainly on differentiation of the P elements , and also on the nature of the basal cavity. This definition has been more or less accepted by Löfgren (1978), Clark et al. (1981), Sweet (1988), and Stouge & Bagnoli (1988). However, Serpagli (1974) considered Baltoniodus to be a subgenus of Prioniodus , while van Wamel (1974) regarded Baltoniodus as a junior synonym of Prioniodus . Many authors ( Cooper, 1981; Sweet, 1988; Dzik, 1994; Nicoll & Ethington, in press) considered that both genera might have been derived independently from species of Acodus , while Oepikodus may have evolved from Prioniodus ( Dzik, 1983; Sweet, 1988) or also from Acodus (Stouge & Bagnoli, 1999) . In a recent revision of Oepikodus, Nicoll & Ethington (in press) suggested the triform alate Sa elements , and relatively larger basal cavity distinguish both Prioniodus and Baltoniodus from Oepikodus . Sa elements of Prioniodus and Baltoniodus have a lateral process on each side and a long posterior process, but lack an anterior process.