The name Hyphessobrycon is derived from the Ancient Greek word “υπελάσσων” (hyphesson), which means “of lesser stature”. This word is used as a prefix in this case, to reflect the smaller size of the fish compared to other members of the genus Brycon. The second part of the name, eschwartzae, is in honor of the artist Eugenia Schwartz. She provided financial support for the collection of specimens that form part of the type material used in the research that led to the discovery of this species. As a gesture of gratitude, the species was named after her.
- Order: Characiformes
- Family: Characidae
The current range of this species is restricted to the Río Madre de Dios watershed in the Madre de Dios region of southeastern Peru. Its known distribution includes the Tambopata National Reserve and areas north of the nearby city Puerto Maldonado, where specimens have been collected. The type locality of this species is located at ‘La Cachuela, Río Madre de Dios, Tambopata, Madre de Dios, at coordinates 12°16’38.2″S, 69°09’8.12″W’.
Male fish have bony hooks resembling hooks on their anal fin, with 5 pairs located on the fourth simple ray and 6-10 pairs on each of the first three branched rays. In contrast, female fish do not possess these hooks and typically have a more substantial body than males.
Hyphessobrycon eschwartzae, also known as the Madre de Dios tetra, is a freshwater fish species found in the Madre de Dios River basin in Peru. It was first discovered in 2008 by German aquarium fish exporter Hans-Georg Evers, and was later described and formally named by Dr. Fernando C. Dagosta in 2010.
Hyphessobrycon eschwartzae belongs to the Characidae family, which is one of the largest families of freshwater fish in the world. This species is small, growing up to 3.5 cm in length, and is known for its striking lateral stripes that run along its body. It has a silver-colored body with a distinctive dark stripe that runs from the eye to the tail, and a red stripe above the dark lateral line.
Hyphessobrycon eschwartzae can be distinguished from other Hyphessobrycon species in the Madre de Dios watershed by its anal fin rays, dentary teeth, premaxillary teeth, and lateral line and dorsal fin scales. It differs from H. loretoensis in having fewer pored scales in the lateral line and fewer scales between the lateral line and dorsal fin. It differs from H. heterohabdus in having fewer lateral scales, fewer pored lateral line scales, fewer predorsal scales, and more maxillary teeth.
Hyphessobrycon eschwartzae is part of the putative H. heterorhabdus-group of closely related species within the genus, which is characterized by a thin, usually dark, lateral body stripe. Lima et al. (2014) proposed a putatively monophyletic H. heterorhabdus-group containing only three species, H. heterorhabdus, H. amapaensis, and H. eschwartzae. These species all possess a well-defined, elongate humeral blotch which is continuous with a dark, well-defined midlateral stripe that becomes blurred towards the caudal peduncle, a longitudinal red stripe extending along the body above the midlateral line, and upper half of the eye red.
Hyphessobrycon was raised by Durbin in Eigenmann (1908) as a subgenus of Hemigrammus, differing from the latter by the absence of scales on the caudal fin. The grouping was revised by Eigenmann (1918, 1921) while Géry (1977) created artificial groups of species based on color pattern. Weitzman & Palmer (1997) hypothesized the existence of a monophyletic assemblage within the genus based on color pattern and male fin morphology that they termed the ‘rosy tetra clade,’ with one of the characters supporting its monophyly being the presence of a prominent dark marking on the dorsal fin.
Hyphessobrycon is a polyphyletic lineage containing several genera. The process of splitting it up has already started, and Malabarba et al. (2012) revalidated the genus Ectrepopterus Fowler, previously considered a synonym of Hyphessobrycon. They also analyzed its relationships within the Characidae in the context of Mirande’s (2010) previous work, but included the type species, H. compressus, for the first time in such a study. The results demonstrated that H. compressus is more closely related to ‘rosy tetra’ representatives such as H. eques, H. pulchripinnis, and H. pyrrhonotus than to other species in the genus.
In summary, Hyphessobrycon eschwartza is a species of fish that can be identified by the presence of bony hook-like structures on the anal-fin of males. Specifically, males possess 5 pairs of these structures on the fourth simple ray and 6-10 pairs on each of the first three branched rays. Females, on the other hand, lack these hooks and are generally heavier-bodied than males. These physical characteristics are important for distinguishing between male and female individuals of this species.
- García-Alzate, C. A., C. Román-Valencia and H. Ortega, 2013 – Revista de Biologia Tropical 61(2): 859-873
Hyphessobrycon taphorni y H. eschwartzae (Teleostei: Characidae) dos nuevas especies de peces de la cuenca del río Madre de Dios, Perú.
- Calcagnotto, D., S. A. Schaefer, and R. DeSalle, 2005 – Molecular Phylogenetics and Evolution 36(1): 135-153
Relationships among characiform fishes inferred from analysis of nuclear and mitochondrial gene sequences.
- Géry, J., 1977 – T.F.H. Publications, Inc.: 1-672
Characoids of the World.
- Malabarba, L. R., V. A. Bertaco, F. R. Carvalho & T. O. Litz., 2012 – Zootaxa 3204: 47-60
Revalidation of the genus Ectrepopterus Fowler (Teleostei: Characiformes), with the redescription of its type species, E. uruguayensis.
- Mirande, J. M., 2010 – Neotropical Ichthyology 8(3): 385-568
Phylogeny of the family Characidae (Teleostei: Characiformes): from characters to taxonomy.
- Oliveira, C. A., G. S. Avellino, K. T. Abe, T. C. Mariguela, R. C. Benine, G. Orti, R. P. Vari, and R. M. Corrêa e Castro, 2011 – BMC Evolutionary Biology 11(1): 275-300
Phylogenetic relationships within the speciose family Characidae (Teleostei: Ostariophysi: Characiformes) based on multilocus analysis and extensive ingroup sampling.
- Weitzman, S. H. and L. Palmer, 1997 – Ichthyological Exploration of Freshwaters 7(3): 209-242
A new species of Hyphessobrycon (Teleostei: Characidae) from the Neblina region of Venezuela and Brazil, with comments on the putative `rosy tetra clade’.
- Zarske, A., 2014 – Vertebrate Zoology 64(2): 139-167
Zur Systematik einiger Blutsalmler oder “Rosy Tetras” (Teleostei: Ostariophysi: Characidae).