Macropsobrycon Eigenmann, 1915

Jerep, Fernando C. & Malabarba, Luiz R., 2011, Revision of the genus Macropsobrycon Eigenmann, 1915 (Characidae: Cheirodontinae: Compsurini), Neotropical Ichthyology 9 (2), pp. 299-312 : 301

Macropsobrycon Eigenmann, 1915

Macropsobrycon Eigenmann, 1915: 16 [key to Cheirodontinae species]; 48 [diagnosis; type species by original designation and monotypy: Macropsobrycon uruguayanae Eigenmann, 1915 :]. - Géry, 1960: 2, 5, 9, 14 [placement in an unnamed group of degenerated of very specialized species with reduced conical teeth]. - Géry, 1965 [listed in a new subtribe of Cheirodontidi [sic], the Aphyoditeini]. - Géry, 1972: 15-18 [inclusion in Aphyoditeini]. - Géry, 1977: 594 [in key to Aphyoditeina genera and species]. - Malabarba, 1998: 218 [phylogenetic diagnosis and relationships to cheirodontine genera; included in the new tribe Compsurini ]. -Malabarba & Weitzman, 1999: 424 [comparison with Acinocheirodon melanogramma ]. -Malabarba et al., 2003: 217 [listed in Cheirodontinae ]. - Mirande, 2009: 8, 11 [listed as Cheirodontinae ]. - Javonillo et al., 2010: 505-507 [relationships within Characidae ].- Mirande, 2010: 528, 531- 532 [listed as Cheirodontinae ].

Diagnosis. Distinguished from other genera of the Compsurini by the jaw teeth elongate and conical or rarely bicuspid. Macropsobrycon is further diagnosed from all characid species except the Cheirodontinae by the presence of cheirodontine synapomorphies (see discussion), and from all cheirodontine genera by the following autapomorphies: (1) a small and elongate black spot is present on the proximal half of the second unbranched dorsal-fin ray, corresponding to the distal half of the first unbranched dorsal-fin ray, sometimes extending over the first unbranched ray and corresponding region of the first branched ray [modified from Malabarba, 1998; originally stated as, black pigmentation along the mid-length of the second unbranched and first 5 branched rays]; (2) presence of a small black spot on the base of unbranched anal-fin rays; (3) Ppresence of a hypertrophied caudal-fin scale on ventral lobe of mature males; (4) 12 th and 13 th principal caudal-fin rays of males with robust retrorse hooks anteriorly directed at their branched portion; (5) 14 th to 18 th principal caudal-fin rays of males with feeble and flexible spinelets along their proximal length, and harder and anteriorly directed spinelets along its distal length; (6) 12 th and 13 th principal caudal-fin rays of males distant from each other, with the fin membrane between these contiguous rays bearing hypertrophied tissues.