Pseudoplatystoma Bleeker, 1862

Uriel Angel Buitrago-Suárez & Brooks M. Burr, 2007, Taxonomy of the catfish genus Pseudoplatystoma Bleeker (Siluriformes: Pimelodidae) with recognition of eight species., Zootaxa 1512, pp. 1-38: 3-8

publication ID

z01512p001

publication LSID

lsid:zoobank.org:pub:A7987452-69A5-4C79-B0F2-29B889EA3E1B

persistent identifier

http://treatment.plazi.org/id/D25A861B-8DAE-4D3E-93DE-9BBB19B28535

taxon LSID

lsid:zoobank.org:act:D25A861B-8DAE-4D3E-93DE-9BBB19B28535

treatment provided by

Thomas

scientific name

Pseudoplatystoma Bleeker, 1862
status

n. sp.

Pseudoplatystoma Bleeker, 1862  ZBK 

Pseudoplatystoma Bleeker, 1862  ZBK  :10. Type species: Silurus fasciatus Linnaeus, 1766  ZBK  . Type by original designation. Gender: neuter. Lundberg and Littmann (2003) stated that Pseudoplatystoma  ZBK  is a valid name by first reviser action of Eigenmann and Eigenmann (1888).

Hemiplatystoma Bleeker, 1862  ZBK  :10. Type species: Platystoma tigrinum Valenciennes, 1840  ZBK  . Type by original designation. Gender: neuter.

The etymology of Pseudoplatystoma  ZBK  is as follows: pseudes, (Greek) for false, platys (Greek), flat and stoma (Greek), mouth.

Bleeker used a combination of characters to diagnose his new genus as follows (words in parentheses are ours)

"Snout strongly depressed. Superior maxilla non -prominent. Intermaxillary (premaxillary) teeth minute, vomero -palatine teeth in four patches. Eyes in dorsal position. Nares anterior and tubulated. Long barbels. Spine (pectoral?) serrated, dorsal (spine?) slender. Anal fin short”.

Other features noted in the literature (e.g., Ringuelet et al., 1967; Dahl, 1971; Mees, 1974) include: flat head with occipital region covered by thin skin; posterior occipital process contacting predorsal plate; fontanel of skull extends from middle of snout to posterior line of eyes, at this point it becomes a groove that reaches the occipital; pectoral fins have one spine and 8 rays; anal fin has one spine and 9 rays; caudal fin is forked with branched rays; branchiostegal rays 14-15. We reevaluated these features.

We found six unique characters to support the monophyly of Pseudoplatystoma  ZBK  : foramen formed by the epioccipital process and pterotic (Fig. 2); the articular has a flange or platform on its proximal lateral side (Fig. 3C); the articular presents a large fossa where a novel muscle originates (see Buitrago - Suárez, 2006 and Fig. 3A); the entopterygoid forms a straight angle (Figs. 4A and B); presence of a foramen between the parhypural and hypural at the joint with the compound centrum (Fig. 5); swim bladder expanded anteriorly with one appendicle departing from the anterolateral region on each side (Fig. 6A -C); spotted caudal fin (Figs. 13 and 14).

As recognized here, the genus contains at least 8 species: P. fasciatum  restricted to the Guyana region; P. punctifer  (formerly recognized as P. fasciatum  from the Amazon River); P. orinocoense  , n. sp., (formerly P. fasciatum  from the Orinoco basin); P. magdaleniatum  , n. sp., (formerly P. fasciatum  from the Magdalena River); P. reticulatum  ZBK  (formerly P. fasciatum  from the Amazon and Paraná rivers); P. corruscans  ZBK  (from the Paraná and São Francisco rivers), P. tigrinum  ZBK  , restricted to the Amazon basin, and P. metaense  , n. sp. (formerly P. tigrinum  ZBK  from the Orinoco River).

Additionally, we recognize two clades of Pseudoplatystoma  ZBK  (see Buitrago-Suárez, 2005), both supported by anatomical characters. In the P. fasciatum  clade ( P. fasciatum  , P. punctifer  , P. orinocoense  , P. magdaleniatum  , P. reticulatum  ZBK  , and P. corruscans  ZBK  ) the anterior fontanel is almost entirely surrounded by the mesethmoid and frontals. The fontanel is surrounded by the mesethmoid, frontal, and supraoccipital in the P. tigrinum  ZBK  clade ( P. metaense  and P. tigrinum  ZBK  only) (Figs. 7 and 8). A tooth patch covers the dorsal surface of ceratobranchial5 and extends beyond 1/3 of the ventral region in the P. fasciatum  clade. The tooth patch on ceratobranchial5 covers only the dorsal surface in the P. tigrinum  ZBK  clade (Fig. 9). In the P. tigrinum  ZBK  clade, the lateral ethmoid bears a small process anteriorly (Fig. 8). The process develops from a ventral elevation that serves as the site for a connection of a bundle of ligaments coming from the entopterygoid. The P. fasciatum  clade lacks this process.

The presence of a median crest in the posterior process of the supraoccipital is uncommon in pimelodines. This feature does not distinguish unambiguously between the two clades, but is present in P. tigrinum  ZBK  , P. metaense  and P. magdaleniatum  (Fig. 7).

Kingdom

Animalia

Phylum

Chordata

Class

Actinopterygii

Order

Siluriformes

Family

Pimelodidae

Loc

Pseudoplatystoma Bleeker, 1862

Uriel Angel Buitrago-Suárez & Brooks M. Burr 2007
2007
Loc

Hemiplatystoma

Bleeker 1862
1862