Systematics of the Neotropical Characiform Genus Pseudocurimata Fernandez-Yepez (Pisces: Ostariophysi)

Vari, Richard P. Systematics of the Neotropical Characiform Genus Pseudocurimata Fernandez-Yepez (Pisces: Ostariophysi). Smithsonian Contributions to Zoology, number 490, 28 pages, 18 figures, 1 table, 1989.—The genus Pseudocurimata Femandez-Yepez (1948) is redefined as a monophyletic subunit of the characiform family Curimatidae. Shared derived features in the position of the first proximal radial pterygiophore of the dorsal fin relative to the neural spines of the anterior vertebrae, the form of the anterior and medial articular surfaces of the second hypobranchial, and the pronounced reduction or complete loss of the second set of uroneurals define Pseudocurimata as a monophyletic lineage. Derived conditions of the second hypobranchial, fourth ceratobranchial, second set of uroneurals, position of the first proximal pterygiophore of the dorsal fin, number of vertebrae, and pigmentation characterize monophyletic clades within the genus or are autapomorphic for species. Pseudocurimata is unique among the genera recognized by Vari (1989) in being endemic to the rivers of the western versant of the Andes. Six species are recognized in Pseudocurimata: P. troschelii (Giinther, 1859), which inhabits the rivers draining into the Gulf of Guayaquil in southwestern Ecuador, and the Rio Zarumilla and Rio Tumbes of northwestern Peru; P. boulengeri (Eigenmann in Eigenmann and Ogle, 1907), which occurs in the rivers in southwestern Ecuador draining into the northern portions of the Gulf of Guayaquil; P. lineopunctata (Boulenger, 1911) of the Rio San Juan, Rio Dagua, and upper Rio Atrato in western Colombia, and the coastal rivers of northern Ecuador; P. patiae (Eigenmann in Eigenmann, Henn, and Wilson, 1914) known only from the Rio Patia in southwestern Colombia; P. peruana (Eigenmann, 1920a) of the Ri'o Chira and Rio Piura in northwestern Peru; and P. boehlkei, a new species from the Rio Esmeraldas basin and possibly the Rio Santiago system of northwestern Ecuador. Curimatus brevipes Eigenmann and Ogle (1907) described on the basis of a specimen originating from an uncertain, possibly Peruvian, locality, and Curimatus aureus Pellegrin (1908) described from specimens collected in the Rio Guayas basin of Ecuador, are both placed as synonyms of Pseudocurimata troschelii. Citations of the occurrence of Curimatus patiae in the coastal rivers of northwestern Peru and those of Curimatus peruanus from the Amazon drainages of Ecuador were misidentifications. The historical zoogeography of the species of Pseudocurimata is discussed. The hypothesis of intrageneric phylogenetic relationships is congruent with a scheme of sequential north to south vicariance events along the western versant of the Andes in northwestern South America. The majority of the species in the genus have discrete allopatric distributions, with some degree of secondary, post-vicariance, dispersal evident in the rivers draining into the northern portions of the Gulf of Guayaquil in the southwest of Ecuador, and possibly in the Rio Santiago system of northwestern Ecuador. OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded in the Institution's annual report, Smithsonian Year. SERIES COVER DESIGN: The coral Montastrea cavernosa (Linnaeus). Library of Congress Cataloging in Publication Data Vari, Richard P. Systematics of the Neotropical characiform genus Pseudocurimata Fernandez-Yepez (Pisces: Ostariophysi) (Smithsonian contributions to zoology ; no. 490) Bibliography: p. SupL of Docs, no.: SI1.27:49O 1. Pseudocurimata—Classification. 2. Pseudocurimata—South Am erica—Classification. I. Title. II. Series. QL1.S54 no. 490 [QL638.C89] 591 s-dc20 [597'.52] 89-600135