Mariano D. Silva was, for a while, a prolific taxonomist of fossil ostracode species recovered from Lower Cretaceous strata of the world famous, Lagerstätte-bearing Santana Group of the Araripe Basin in northeastern Brazil (Silva, Reference Silva and Tinoco1978a, Reference Silva and Tinocob, Reference Silva and Tinococ, Reference Silva1979a, Reference Silvab, Reference Silvac). Unfortunately, most of the specimens that he designated as types were not correctly handled and ended up lost, which led a couple of authors to later raise neotypes for some of these species. According to the ICZN (Ride et al., Reference Ride, Cogger, Dupuis, Kraus, Minelli, Thompson and Tubbs1999, Art, 72.2), “a nominal species-group taxon established before 2000 may have its name-bearing type fixed from the type series … originally … or subsequently. (If no name-bearing type is believed to be extant a neotype may be fixed …).” From a type series, if performed by the original author, types can be fixed as: (1) a holotype (the single name-bearing specimen that is the sole representative of a named species group); or (2) paratypes (all non-name-bearing specimens other than the holotype upon which a species-group name is based and so designated). Syntypes are name-bearing specimens not designated as holotypes or paratypes; when performed by subsequent authors, one of the syntypes can be fixed as a lectotype (same function as the holotype), whereas others can act as paralectotypes (equivalent to paratypes).

If no type is believed to be extant, a name-bearing neotype can be fixed, following provisions of the ICZN (Ride et al., Reference Ride, Cogger, Dupuis, Kraus, Minelli, Thompson and Tubbs1999, Art. 75.4) that the “first neotype designation published for a nominal species-group taxon in accordance with the provisions of this Article is valid and no subsequent designation, except one made by the Commission under the plenary power … has any validity.” Do Carmo et al. (Reference Do Carmo, Rafael, Vilhena and Tomassi2004), for example, aimed at raising 10 neotypes (p. 153) for Theriosynoecum silvai (Silva, Reference Silva and Tinoco1978a) and seven (p. 156) for Alicenula martinsi (Silva, Reference Silva and Tinoco1978c). Meanwhile, Tomé et al. (Reference Tomé, Lima Filho and Neumann2014, p. 158), while reviewing Cypridea araripensis Silva, Reference Silva and Tinoco1978b, proposed “an amendment with the choice of a neotype and several paratypes,” despite the impossibility of subsequent authors naming paratypes for any previously created species.

To solve such nomenclatural inconsistencies, it is necessary to clarify which subsequent type designations are currently valid (according to the ICZN) for Theriosynoecum silvai, Alicenula martinsi, and Cypridea araripensis as designated by Do Carmo et al. (Reference Do Carmo, Rafael, Vilhena and Tomassi2004) and Tomé et al. (Reference Tomé, Lima Filho and Neumann2014). The specimen MP-O-1797 (see Table 1), being the first mentioned by Do Carmo et al. (Reference Do Carmo, Rafael, Vilhena and Tomassi2004) as the neotype of T. silvai, is the neotype of said species. For A. martinsi, MP-O-1897, being the first specimen mentioned by Do Carmo et al. (Reference Do Carmo, Rafael, Vilhena and Tomassi2004) as the neotype of the species, is its neotype. The paratypes of Cypridea araripensis as given by Tomé et al. (Reference Tomé, Lima Filho and Neumann2014) are invalid as such; only its neotype should be considered a type specimen for the species.

Table 1.

Full review of the typification status of specimens of Theriosynoecum silvai (Silva, Reference Silva and Tinoco1978a), Alicenula martinsi (Silva, Reference Silva and Tinoco1978c), and Cypridea araripensis Silva, Reference Silva and Tinoco1978b currently designated as types. 1 = after Do Carmo et al. (Reference Do Carmo, Rafael, Vilhena and Tomassi2004); 2 = after Tomé et al. (Reference Tomé, Lima Filho and Neumann2014); 3 = ‘MP-O’-prefixed specimens housed at the Museu de Paleontologia Irajá Damiani Pinto, Porto Alegre, Brazil; ‘Nº. DG-CTG-UFPE’-prefixed specimens housed at the Microfossil Collection of the Geology Department of the Federal University of Pernambuco, Recife, Brazil

¹ After Do Carmo et al. (Reference Do Carmo, Rafael, Vilhena and Tomassi2004).

² After Tomé et al. (Reference Tomé, Lima Filho and Neumann2014).

³ “MP-O”-prefixed specimens housed at the Museu de Paleontologia Irajá Damiani Pinto, Porto Alegre, Brazil.

⁴ “Nº. DG-CTG-UFPE”-prefixed specimens housed at the Microfossil Collection of the Geology Department of the Federal University of Pernambuco, Recife, Brazil.