Petitella

Petitella
Petitella bleheri
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Characiformes
Family:	Acestrorhamphidae
Subfamily:	Megalamphodinae
Genus:	Petitella Géry & Boutière, 1964 [1]
Type species
Petitella georgiae Géry & Boutière, 1964 [1]

Petitella is a genus of freshwater ray-finned fishes belonging to the family Acestrorhamphidae, the American characins, of the order Characiformes. The fishes in this genus are found in South America.

They are all popular tropical fish in the aquarium hobby. They are commonly known as Rummy-nose tetras.

Taxonomy and systematics

Petitella was first proposed as a monospecific genus in 1964 by the French ichthyologists Jacques Géry and Henri Boutière with Petitella georgiae as its only species, which they also designated as the type species of the genus. ^[1] This genus was formerly monotypic, featuring only P. georgiae. The other two species were allocated to Hemigrammus . Before the reallocation in 2020, ^{[2] [3]} This genus is classified within the subfamily Megalamphodinae, the red tetras, within the American Characin family Acestrorhamphidae. ^[4] This family is classified within the suborder Characoidei of the order Characiformes. ^[5]

Species

Petitella contains the following valid species: ^[6]

• Petitella bleheri (Géry & Mahnert, 1986) (Firehead tetra)
• Petitella georgiae Géry & Boutière, 1964 (False rummynose tetra)
• Petitella rhodostoma (Ahl, 1924) (Rummynose tetra)

References

1. Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Genera in the family Megalamphodinae". Catalog of Fishes . California Academy of Sciences . Retrieved 17 October 2025.
2. Jeremy Gay (14 July 2020). "Rummynose tetras combine into a single genus". Fishkeeping News. Retrieved 28 December 2023.
3. Bittencourt, Pedro Senna; Machado, Valéria Nogueira; Marshall, Bruce Gavin; Hrbek, Tomas; Farias, Izeni Pires (2020). "Phylogenetic relationships of the neon tetras Paracheirodon spp. (Characiformes: Characidae: Stethaprioninae), including comments on Petitella georgiae and Hemigrammus bleheri". Neotropical Ichthyology. 18 (2). doi: 10.1590/1982-0224-2019-0109 .
4. Melo, Bruno F; Ota, Rafaela P; Benine, Ricardo C; et al. (2024-09-01). "Phylogenomics of Characidae, a hyper-diverse Neotropical freshwater fish lineage, with a phylogenetic classification including four families (Teleostei: Characiformes)" . Zoological Journal of the Linnean Society. 202 (1) zlae101. doi:10.1093/zoolinnean/zlae101. ISSN   0024-4082.
5. R. Fricke; W. N. Eschmeyer; R. Van der Laan (2025). "ESCHMEYER'S CATALOG OF FISHES: CLASSIFICATION". California Academy of Sciences. Retrieved 17 October 2025.
6. Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Petitella". Catalog of Fishes . California Academy of Sciences . Retrieved 17 October 2025.