TT 81-52039 UNIVERSIDAD NACIONAL AUTONOMA DE MEXICO Facultad de Ciencias Departamento de Bioiogia THE NATIONAL UNIVERSITY OF MEXICO Faculty of Sciences Department of Biology Crayfishes of Mexico (Crustacea: Decapoda) [Cambarinos de la Fauna Mexicana: Crustacea Decapoda] ALEJANDRO VILLALOBOS, M. en C.B. Mexico, 1955 Translated from Spanish Published for the Smithsonian Institution Libraries, and the National Science Foundation, Washington, D.C, by Amerind Publishing Co. Pvt. Ltd., New Delhi 1983 © 1983 Smithsonian Institution Published for the Smithsonian Institution Libraries, pursuant to an agreement with the National Science Foundation, Washington, D.C., by Amerind Publishing Co. Pvt. Ltd., 66Janpath, New Delhi 110001 Translator: Morton H. Hobbs,Jr. Phototypeset by Anil Printers, New Delhi and printed at Baba Barkhanath Printers, New Delhi, India Foreword Because of the relative inaccessibility of this important, privately printed monograph dealing with the Mexican crayfishes, I have been urged by several of my colleagues to make my translation of it available. The value of this work lies in the fact that it brings together all previously published information concerning the Mexican crayfishes and includes detailed descriptions and excellent illustrations of most of the described Middle American crayfishes. Equally important are the sections devoted to dis­ cussions of relationships and distribution that must be taken into account in future studies of the North and Middle American crayfishes and their symbionts. As Dr. Villalobos has pointed out in the initial sentence of the Introduc­ tion, much of the text consists of a compilation of his prior contributions to our knowledge of the Mexican crayfish fauna, and, as might be anticipated, some inconsistencies have resulted. The Spanish text has been adhered to as closely as possible, with occasional bracketed insertions of words or phrases that are intended to clarify interpretations. For the sake of uniformity, the keys and diagnoses are presented in telegraphic style, and descriptions and discussions in complete sentences. Attempts have been made to render the synonymies uniform, and some corrections in typographical errors and page and figure references have been made; inconsistencies in the spelling of scientific names of the crayfishes, however, have been preserved. The page numbers of the Spanish text appear in the left-hand margin. The translation has been prepared over a period of several years, and, without the invaluable assistance of Isabel P^rez Farfante, a colleague at the Smithsonian Institution, I should not have considered offering the manu­ script for publication. To her, I am indeed most grateful, as I am to Margaret A. Daniel who prepared the photocopies of the plates and worked with me in attempting to ferret out inconsistencies and errors in the typescript. I also extend my thanks to Georgia B. Hobbs for her comments on drafts of the manuscript and to C. W. Hart, Jr., another colleague at the Smithsonian, for his part in arranging for its publication. Finally, appreciation is extended to my friend Alejandro Villalobos F. for approving the publication of the translation of his monograph. Horton H. Hobbs, Jr. 111 To my parents Acknowledgment I wish to express my appreciation to Dr. Enrique Rioja for his wise direction and his scholarly counsel during the preparation of this thesis. Likewise, to all of my teachers in the Faculty of Sciences, to whom I am indebted for the knowledge I acquired in the various areas of my profession, and to my colleagues in the Instituto de Biologia who offered me their esteem and affection. VI Preface It is with satisfaction that I devote a few lines to the monograph that Dr. Alejandro Villalobos has dedicated to the Mexican crayfishes; I have observed the development of the study since its inception; the author and I have shared the same laboratory, I have followed his work day by day since the beginning of his scientific investigations; because of this, I have knowledge of his anxieties and satisfactions. These reasons are responsible for my intimate pleasure in seeing this important study published. With this work Professor Villalobos has become an accomplished investigator in the field of Zoology, capable of undertaking other studies, which all anticipate, and I more than any, in a variety of carcinological areas. His scientific rigor and his thoroughness have placed him among the outstanding specialists in his field. We hope that this publication is the first fruit of a full harvest Enrique Rioja vn Contents Foreword v Preface vii Introduction xi Introductory Part Methods of Collection and Preservation 3 Taxonomic Position 8 Distribution of the Parastacids and Astacids in the World 10 Paleontological Origin of the Astacura and Their Possible Emigrations (Plate 1) 15 History of the Study of the Mexican Crayfishes 19 Monographic Studv of Carnharellus montezumae montezumae (Saussure) (Plate 2) 26 General Considerations Concerning the Morphological Characters Utilized in the Svstematics of Cambarinae 41 Taxonomic Part Taxonomic Study of the Mexican Genera of Crayfishes 49 Subfamily Cambarinae 49 Genus Procambarus 50 barbatus Section 50 Procambarus sirnulans regiomontanus Villalobos 51 Procambarus digueti (Bouvier) 58 Procambarus bouvieri (Ortmann) 64 Systematic Discussion of the Mexican Species of the baroatus Section 70 blandingii Section 71 Procambarus blandingii cuevachicae (Hubbs) 72 Procambarus toltecae Hobbs 81 Procambarus caballeroi Villalobos 86 ix Taxonomic Discussion of the Mexican Species of the blandingii Section 93 riojae Section 94 Procambarus riojae (Villalobos) 95 Procambarus hoffmanni (Villalobos) 100 Procambarus hortonhobbsi (Villalobos) 105 Procambarus teziutlanensis (Villalobos) 112 Procambarus tlapacoyanensis (Villalobos) 119 Procambarus erichsoni Villalobos 127 Procambarus contrerasi (Creaser) 137 Procambarus zihuateutlensis Villalobos 144 Taxonomic Discussion of the Species of the riojae Section 150 mexicanus Section 153 Procambarus mexicanus (Erichson) 156 Procambarus aztecus (Saussure) 163 Procambarus rodriguezi Hobbs 170 Procambarus veracruzanus Villalobos 171 Procambarus vazquezae Villalobos 176 Procambarus ruthveni (Pearse) 183 Procambarus ruthveni zapoapensis Villalobos 192 Procambarus mirandai Villalobos 200 Procambarus acanthophorus Villalobos 209 Procambarus llamasi Villalobos . 214 Procambarus pilosimanus (Ortmann) 220 Genus Paracambarus 228 Paracambarusparadoxus (Ortmann) 228 Paracambarus ortmannii Villalobos 235 Genus Cambarellus 242 Cambarellus montezumae montezumae (Saussure) 243 Cambarellus montezumae zempoalensis Villalobos 244 Cambarellus montezumae lermensis Villalobos 249 Cambarellus montezumae patzcuarensis Villalobos 252 Cambarellus alvarezi Villalobos 255 Cambarellus montezumae var. tridens (Von Martens) 261 Cambarellus montezumae dugesii (Faxon) 261 Cambarellus montezumae areolatus (Faxon) 262 Cambarellus montezumae occidentalis (Faxon) 262 Cambarellus chapalanus (Faxon) 262 General Considerations Concerning the Present Distribution of the Crayfishes of Mexico 264 Bibliography 273 x Introduction The present thesis consists of a resume of the studies made concerning the Mexican crayfishes which have appeared in various volumes of the Anales del Instituto de Biologia de la Universidad Nacional Autonoma de Mexico. They represent a continuous effort throughout most of 10 years, obtaining systematic collections in the type localities of species previously described and in other areas from which we have obtained new forms. The redescription of some of the species established by other authors, for which it was necessary to describe in more detail and precision, and descriptions of the species and subspecies of new discoveries by me constitute only a small portion of what must be learned concerning the Mexican crayfish fauna, one surely very rich in endemic species. My task began with the redescription of Cambarellus montezumae montezumae and some of its new subspecies, and as the possibilities for collecting arose, the acquisition of crayfishes has been increased and progressively augmented. As a result of this work, at the present time the Mexican crayfish fauna is represented by 37 to 40 known species of which 16 were described by foreign authors. The crayfishes are freshwater decapod crustaceans which populate a large part of the streams and lacustrine deposits of Guatemala, Mexico, Cuba, and the United States. Some have become adapted to cave life; others dig burrows in wet earth, in which they endure, as a result of their great biological resistance, unfavorable environmental conditions. Almost all of them have nocturnal habits, and in the darkness they crawl about the streams in search of food; during the day, they remain concealed beneath stones or debris, or within the tunnels which they have made. I must confess that little progress has been made in Mexico in studying their biology and only by analogy with the studies conducted in the United States have I been able to verify many details of their mode of life, but I have had the opportunity to observe some peculiar habits of the Mexican species during my investigations. In this monographic study, all of the work that has been accompli­ shed since the original investigations of the crayfishes of Mexico has been brought together their taxonomic relationships and geographic distribution, including moreover descriptions of the species and keys to xi them and to the genera to which they belong. It is important to notice that