Zur Systematik einiger Blutsalmler oder "Rosy Tetras" (Teleostei: Ostariophysi: Characidae) PDF

Abstract

The species Hyphessobrycon bentosi Durbin in Eigenmann, 1908, Hyph. jackrobertsi spec. nov., Hyph. paepkei spec. nov., Hyph. sweglesi (Géry, 1961) and Hyphessobrycon dorsalis spec. nov. are described after a short historical introduction. Hyph. bentosi and Hyph. “robertsi” are treated as valid species contrary to Weitzman & Palmer (1997 ff) and Hyph. “robertsi” is scientifically described for the first time as Hyph. jackrobertsi spec. nov. The name Hyph. “robertsi” is broadly distributed in the literature but no valid description was found. Hyphessobrycon bentosi from the surroundings of Obidos (type-locality) is characterized by its (1) relatively low body. The body depth is 2.85 (2.67 to 3.17) times in SL. (2) Maxillary bone with three to eight (to ten; x = 5.25) conical or tricuspid teeth. (3) Anal-fin with 23 to 26 branched fin rays (x = 24.71). (4) 30 to 32 longitudinal scales (x = 31.54). (5) 5/1/4 transversal scales before the dorsal-fin. (6) The fin rays of the dorsal-fin reach not to the adipose-fin in adults. (7) An sexual dimorphism in the dorsal- and anal-fin as in Hyph. jackrobertsi spec. nov. and Hyph. paepkei spec. nov. is not developed. (8) The basic coloration of the body is plain olive brown and not so intensive red as in Hyph. jackrobertsi spec. nov. Hyph. jackrobertsi spec. nov. from the río Pastaza basin of Peru is characterized by (1) a relatively high body (body depth 2.48 (2.31 to 2.73) time in SL) and (2) a longer anal- and dorsal-fin rays. There are intersects between Hyph. jackrobertsi spec. nov. and Hyph. bentosi in the body depth in juvenile specimens, adults are well differentiated. Hyph. jackrobertsi spec. nov. is similar to Hyph. bentosi in the number of maxillary teeth (five to nine conical or tricuspid teeth (x = 6.95)). Hyphessobrycon paepkei spec. nov. from the rio Demini basin of Brazil if differentiated by all known members of the rosy-tetra-group (except Hyph. melanopterus (Eigenmann, 1915)) by its (1) higher number of maxillary teeth (14 to 21 conical to tricuspid teeth (x = 15.98) and (2) the shape of anal-fin. There are two color forms of Hyph. sweglesi (Géry, 1961), which are conspecific, similar to Hyph roseus (Géry, 1960). Hyphessobrycon dorsalis spec. nov. from the rio Caures basin of Brazil is characterized by the following combination of features (1) a relatively elongated body (body depth 3,59 (3.41 to 3.76) times in SL), (2) basis of caudal-fin with two large scales, (3) praemaxillary bone with two rows of teeth (two tricuspid teeth, seldom one tricuspid tooth in the external row and six tricuspid teeth in the internal row), (4) maxillary bone with three to four tricuspid teeth, (5) anal-fin with iii 21 to 23 rays, (6) scales: 4 – 5/(5 – 7)31 – 32/3, (7) a distinctly developed pseudotympanum, (8) a black spot in the dorsal-fin and (9) no humeral spot.