Comprehensive DescriptionRead full entry
Sturisoma Swainson, 1838 .
Type species: Loricaria rostrata Spix & Agassiz, 1829 ZBK . Brazilian rivers.
Holotype : lost ( Isbrücker 1979).
The species of the genus Sturisoma are widely distributed on both slopes of the Andes, in Panama and Colombia, and in the Amazon, Orinoco, and Paraná River basins. Sturisoma inhabit gently to swiftly flowing white waters (Evers & Seidel 2005) where submerged wood is abundant in the main flow of rivers. Sexual dimorphism includes hypertrophied odontodes on the sides of the head of the male. As representatives of Farlowella ZBK , Sturisoma species are open brooders (pers. obs.). Kavalco et al. (2005) reported a diploid number of 2n = 74 chromosomes for the single species characterized: S. cf. nigrirostrum . A neotype has yet to be designated for Sturisoma rostratum , the type species, which was destroyed during World War II ( Isbrücker 1979). Neotype designation is needed to fix the type locality, which is unspecified and may pertain to several of the currently recognized species. Ghazzi (2003) revised genus, but it remains unpublished and unavailable for the moment. Sturisoma has been shown to be sister to Farlowella ZBK according to Rapp Py-Daniel (1997) and Montoya-Burgos et al. (1998). Ghazzi (2005) confirms this relationship. Sexual dimorphism and reproductive strategy are comparable in both genera and tend to corroborate the molecular and morphological data. Fifteen valid species are currently recognized (Ferraris 2003, Ghazzi 2005). Ghazzi (2005) described a new species, Sturisoma kneri ZBK , replacing an unavailable name, Loricaria kneri ZBK , proposed by Tortonese (1940). She argued (p. 564) that “Tortonese’s (1940) intention was solely to publicize the large number of species housed in Museo di Torino; it was not his intention to validate De Filippi ’s manuscript names.” However Tortonese (1940: p. 134-135) explained in his introduction: “Infine, ho avuto anch ’io la ventura di trovare nei nuclei di materiale da me studiato diversi Pesci che ho creduto dover attribuire a specie non ancora note” In this citation we can see the intention of Tortonese to publish the names of new species, in part from De Filippi’s manuscript. The name Loricaria kneri De Filippi in Tortonese, 1940 ZBK is here used as the valid name of this species, because the author refers to a holotype and because he gives a short diagnosis according to De Filippi’s manuscript. Thus, Tortonese made the name Loricaria kneri De Filippi ZBK available. Secondly, Tortonese proposes that L. kneri ZBK could be a representative of the genus Sturisoma as he specified in his introduction: “Ciascuna specie è elencata secondo l'ordine sistematico, col nome dell’A. che per primo la descrisse: ad esso seguono, oltre le indicacazioni bibliografiche, il nome coretto - se il primo è passato in sinonimia o vi è stato cambiamiento di genere - il numero che il materiale porta nel Catalogo della collezione e i dati relativi alla provenienza, al raccoglitore o donatore e allo stato attuale di conservatione.” The statement on the validity of Loricaria kneri De Filippi in Tortonese, 1940 ZBK should be submitted to the International Commission on Zoological Nomenclature.