Phylogenetic diagnosis and expanded description of the genus Mazarunia Kullander, 1990 (Teleostei: Cichlidae) from the upper Mazaruni River, Guyana, with description of two new species

  • Hernán López-Fernández, Donald C. Taphorn und Elford A. Liverpool

    Abstract

    We expand the description of the genus Mazarunia Kullander, 1990, explore morphological diagnostic characters for the genus and for its sister-group relationship with Guianacara Kullander & Nijssen, 1989 in a phylogenetic context, expand the description of M. mazarunii and describe two new species. Mazarunia can be diagnosed by the combination of numerous anatomical traits, including the unique loss of infraorbital 6, the configuration of the first epibranchial in two of the species, a well-developed posteroventral lateral expansion of the palatine that is largely contiguous with the ectopterygoid, the absence of a suture between the hyomandibular and the metapterygoid, the absence of an interarcual cartilage, fourth ceratobranchial with 2 or 3 tooth plates, a caudally scaled interoperculum, equal-sized scales in the ventral and lateral chest regions, a simple, disjunct pattern of lateral line squamation, and smooth preopercle, supracleithrum and extrascapula. Species of Mazarunia can be further distinguished from species of their sistergenus Guianacara by their distinct color patterns. Mazarunia charadrica, new species, can be distinguished from other species of Mazarunia, among other characters, by approximately equal uncinate process and anterior arm and reduced anteroventral expansion of epibranchial 1 (vs. uncinate process narrower and complete anteroventral expansion in the other two species), a dorso-ventrally flattened maxillary process of the palatine (vs. cylindrical in the other two species), cycloid (vs. ctenoid) scales in the opercular, postorbital, lateral chest and anal-genital regions, the absence of a mid-lateral spot, and a diffuse dark area covering the dorsal portion of the head giving the impression of a “black cap”. ...
    Quelle: Neotropical Ichthyology, 10(3):465-486, 2012 (Öffentlich)

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