Bulletin Alabama Museum of Natural History BULLETIN ALABAMA MUSEUM NATURAL HISTORY is published by the Alabama IVluseum of Natural History, The University of Alabama. The BULLETIN is devoted primarily to the subjects of Anthropology, Archaeology, Botany, Geology and Zoology of the Southeast. The BULLETIN will appear irregularly in consecutively numbered issues. Manuscripts will be evalualed by the editor and an editorial committee selected for each paper. Authors are requested to conform with the CBE Style Manual, 3rd edition, 1972, published by the American Institute of Biological Science, \Vashington, D.C. An abstract not exceeding three percent of the original text or four pages must accompany the manuscript. For information and policy on exchanges, write to the Librarian, The University of Alabama, Box S, University, AI. 35486. Numbers may be purchased individually; standing orders are accepted. Re­ mittances should accompany orders and made payable to The University of Alabama. Communication concerning manuscripts, editorial policy, and orders for indi­ vidual numbers should be addressed to the editor: Herbert Boschung Alabama Museum of Natural History The University of Alabama Box 5897 University, Alabama 35486 When citing this publication authors are requested to use the following abbre­ ,'iation: Bull. Alabama Mus. Nat. Hist. Price this number: $3.00. NUMBER 4,1978 1 Systematics of the Percid Fishes of the Subgenus Microperca, Genus Etheostoma Brooks M. Burr Department of Zoology, Southern Illinois University, Carbondale, Illinois 62901 ABSTRACT: Burr, Brooks M., Systematia of the Percid Fishes of the Subgenus Microperca, Genus Etheostoma. Bulletin Alabama Museum of Natural History, Number 4, 53 pages, 19 figures, II tables, 1978. The objectives of this study are threefold: first, to describe the intraspeci· fic variation of morphological characteristia in populations of the subgenus Microperca; second to map and discuss the distributions of the species; and third, to clarify both the intra· and interspecific relationships of the subgenus. More than 25 meristic characters were examined on approximately 1200 specimens of E. proeliare (Hay); 200 specimens of E. fonticola (Jordan and Gilbert); and 2000 specimens of E. microperca Jordan and Gilbert. Sixteen proportional mea· surements were taken from 40 to 70 specimens of each species. Spot distribution maps, and a figure of both sexes of each species are included. Information from life history studies (to be published separately) is included in the taxonomic analyses. The subgenus is diagnosed and its subgeneric status discussed. Microperca displays an array of derived morphological and life history characteristia that establish it as the most specialized group of darters. The three species in the subgenus inhabit heavily vegetated standing water bodies on the Coastal Plain, in the Mississippi Valley and/or the Great Lakes drainages where they are distributed mostly allopatrically. E. proeliare is distinguished from the other two species by higher meristic values for several characters, different color pattern, more complete squamation, and a greater maximum standard length. Variation in the species is minor although notable geographic trends in squamation, maximum size, and some meristic characters were found. E. proeliare inhabits Coastal Plain streams and lakes from western Florida north to Dlinois and southwest to the San Jacinto River, Texas. E. fonticola, a nationally recognized endangered species, is presently restricted to the luxuri· antly vegetated springs at San Marcos, Texas. It formerly occurred in Comal Spring at New Braunfels, Texas, but has recently been extirpated. This species is distinguished from the other two species by differences in color, squamation, body proportions, maximum standard length, and some meristic features. Specimens available from both populations are about 90 percent separable in number of pectoral rays and second dorsal fin pigmentation. The most variable species, E. microperca, is distinguished from the other two species by numerous features, chief of which are cephalic lateral line characters, brighter colors, many meristic features and shape of the female genital papilla. The species is widespread in the upper Mississippi River valley and Great Lakes drainages and has disjunct populations in the Ozarks of Missouri, Kansas, Arkansas, and Oklahoma. It occurs syntopically with E. proeliare in one stream in Oklahoma. Throughout the Great Lakes populations the configuration of the infra· orbital canal is variable, but makes some geographic sense. Ozark populations of the species are the only North American percids known with tubercles developed on their dorsal fins. However, Ozark populations are in various stages of differentiation and no new taxa are recognized. The subgenus Microperca is considered to be most closely related to the subgenus Hololepis based on similarities in morphology and life history. Within the subgenus Microperca there are two groups: one containing E. proeliare and E. fonticola and the other containing E. microperca. The former group shares a more completely developed lateralis system, bilobed genital papillae in females, tubercles well developed on anal aDd .pelvic fins of breeding males, and similar fin pigmentation patterns. E. microperca has an extremely reduced lateralis system, conical female genital papilla, tubercle distribution usually reduced on anal fin of breeding males, and bright orange or red male pelvic and anal fin color. E. proeliare and E. fonticola are the most primitive species in the subgenus since they have retained the greater number of ancestral character states. E. microperca is the most specialized member of the subgenus and probably the most specialized North American percid. Editorial Committee for this paper: Dr. Bruce B. Collette, NOAA, National Museum of Natural History, Washington, D.C. 20560. Dr. Lawrence M. Page, Illinois Natural History Survey, Urbana, IL 61801. Dr. Philip W. Smith, Illinois Natural History Survey, Urbana, IL 61801. 2 BULLETIN ALABAMA MUSEUM NATURAL HISTORY Introduction grant to L. M. Page. The Illinois Natural History Survey provided salary. office space. equipment, and transporta­ The subgenus Mieroperca consists of three darters in tion facili ties. the genus Etheostoma, tribe Etheostomatini, family Per­ cidae, and order Perciformes. They are the smallest dart­ I am grateful to the following curators. staff. or stu­ ers and, as a group, among the smallest freshwater fishes dents and their institutions (abbreviations used through­ in North America. Phylogenetically they are nearest the out the text) for granting specimen loans, information species in the subgenus Hololepis, from which they differ concerning types, laboratory space and numerous other in a number of morphological features. Microperca is courtesies: Albert P. Blair (APB), University of Tulsa; considered to be the most derived component in the evo­ Anthony A. Echelle. Baylor University (BU); Eugene C. lution of Etheostoma, and the group displays a number Beckham. formerly at Cornell University (CU); Branley A. Branson, Eastern Kentucky University (EKU); Robert of highly specialized characteristics. The species of Microperca are primarily sluggish-stream K. Johnson and Garrett S. Glodek. Field Museum of Nat­ ural History (FMNH); Ralph W. Yerger. Florida State inhabitants, often associated with cool waters and aquatic University (FSU);Henry W. Robison (HWR). Southern vegetation, although they are also found in lakes and Arkansas University; Lawrence M. Page and Philip W. springs of moderately high temperatures. Two of the spe­ Smith. Illinois Natural History Survey (INHS); Frank B. cies are primarily spring spawners. and all three have Cross. University of Kansas (KU); Robert Schoknecht. one-year to 18-month life cycles. Some populations of formerly at Museum of Comparative Zoology (MCZ); two of the species probably spawn almost the year around Max A. Nickerson. Milwaukee Public Museum (MPM); in the constant-temperature springs that they inhabit. Glenn H. Clemmer, Mississippi State University (MSU); The adult size is usually between 25 and 35 mm standard William M. Palmer. North Carolina State Museum length. (NCSM); Neil H. Douglas and John A. Harris. Northeast The three species in the subgenus are E. proeliare, E. Louisiana University (NLU); Rudolph Miller. Okla­ fontieola and E. mieroperca. In general they are distrib­ J. homa State University (OAM); Ted M. Cavender and uted allopatrically from Ontario. Michigan, Minnesota. Milton B. Trautman. Ohio State Museum (OSM); Loren and Wisconsin south through the Great Lakes and Missis­ G. Hill and William Matthews. University of Okla­ sippi Valley to the panhandle of Florida and the Guada­ J. homa (OUMZ); E . Crossman and formerly W. B. lupe River of Texas. However, sympatry occurs between .J. Scott. Royal Ontario Museum (ROM); Tomio Iwamoto. two species in the Arkansas and Red rivers of Oklahoma. California Academy of Sciences including former Stan­ Morphological information on the species of Micro­ ford University collection (SU); John D. McEachran, perea has been limited to surveys of a few characters such Texas A 8c M University (TCWC); Thomas M. Buc­ as vertebral counts (Bailey and Gosline, 1955); branchial hanan (TMB). Westark Community College; Robert apparatus (Branson and Ulrikson. 1967); breeding tuber­ F. Martin and Clark Hubbs. University of Texas Na­ cles (Collette. 1965); and the lateralis system (Page. 1977). tural History Collection