NATIVE PISCIFAUNA OF UTAH LAKE A. GAYLON COOK BIOCONSERVATION INTERNATIONAL 3306 N CANYON RD PROVO UT 84604-4548 Running Head: NATIVE PISCIFAUNA OF UTAH LAKE NATIVE PISCIFAUNA OF UTAH LAKE A. Gaylon Cook' ABSTRACT.— A thorough search of the descriptive and systematic ichthyological literature disclosed the piscine specimens from Utah Lake, and manifested an elaborate web of supposed synonyms for which there were nomenclatural as well as species-assignment errors. In this review, the characteristics of piscine examples from Utah Lake, and forms that have been considered to be their conspecifics, are delineated and contrasted; deductions about valid synonyms are made. A careful comparison of the morphologic descriptions of exemplars of Utah lake forms and their putative conspecifics requires that the synonymies of several taxa be pared. By providing a comprehensive bibliography, and furnishing winnowed synonymies of Utah Lake forms that signal which forms to reexamine, this paper establishes a basis for needed chemical taxonomic analyses such as DNA-DNA hybridization tests. Also, the detailed descriptions of taxa available herein constitute a resource that can be used for such purposes as distinguishing species in periodic ichthyological surveys of Utah Lake or identifying taxa (e.g., suckers) during endangered species recovery-plan activities. Key Words: piscifauna, ichthyofauna, Utah Lake, fish, fishes, taxonomy, systematics, synonymy, native. Utah Lake, closely bordered by the city of Provo, is a 38,800-ha body of fresh water in central Utah measuring 23.5 by 38.0 km (Carter 1969: 2, Radant and Sakaguchi 1981: derived from Fig. 1). It has an average depth of 2.9 m and a maximal depth of 4.2 m (Radant and Sakaguchi 1981: 2). Formerly it collected a flow of 740 million m3/yr (Arnold 1960: 11-17). Jordan and Gilbert (1881) provided the first report on the ichthyofauna of Utah Lake; 1 form collected near Evanston, Wyoming was included. Although Jordan (1891) furnished an account of the fishes of Salt Lake Valley and Utah Valley, whose combined areas he considered to constitute "Salt Lake Basin", the next treatise specifically treating the piscifauna of Utah Lake was Hatton's (1932) review. The most recent document on this subject was an article by Heckmann et al. (1981) whose cursory treatment of native fishes consisted principally of an unreferenced annotated list. La 'Bioconservation International, Provo, Utah 84604-4548. GREAT BASIN NATURALIST 2 Rivers' (1962) reference contains synonymic lists for most of the ichthyofauna of Utah Lake. No work has comprehensively characterized these fishes or unsnarled and expounded their synonymies. Many publications (see below) have treated 1 piscine taxon from Utah Lake. In totality, they evince multiple nomenclatural errors, and remarkably extensive synonymies for most taxa due partially to age-related differential morphologies. Herein, the chronologies and explanations of reported (and often inordinate) synonymies, are based on a perusal of a plethora of descriptive or taxonomic documents pertaining to native Utah Lake fishes or putative synonyms. All were scrutinized and compared to reveal corroborations, or discrepancies and contradictions. Piscine taxonomy has been affected most by the massive lumping of species by Jordan and Evermann (1896a,b, 1898a,b). That action's impact persists. Of the 11 piscine forms from Utah Lake that were considered to be species by Robins et al. (1991), 8 were regarded as polytypic by Mayden et al. (1992: table 1). Ignorance about the phylogenetic relationships of Utah Lake fishes is underscored by the dispute about the number of sucker species present (see below). Significantly, it is not known whether certain piscine taxa of Utah Lake constitute endemic species or subspecies that would be worthy of endangered status. The principal aim of this review is to establish a sound basis for defining and delimiting as precisely as possible the native piscifauna of Utah Lake. It is hoped that it will lay the groundwork for further systematic investigations. Taxonomic studies employing DNA-DNA hybridization analyses, as well as those that might utilize biochemistry, immunology, serology, protein sequencing, or comparative anatomy, need to be performed on Utah Lake's native fishes and their putative conspecifics. Besides being quick, DNA hybridization offers the most precise quantitative comparisons (Sibley and Alquist 1990: 3). It is also anticipated that the characterizations that are presented here will assist ichthyologists in identifying Utah Lake fishes. For example, descriptive data on catostomids can be used by field biologists with the Utah Department of Natural Resources, Division of Wildlife Resources in their effort to identify endangered adult June Suckers (Chasmistes Bow), and distinguish them from Webug Suckers (Chasmistes fecundus) and Utah Suckers (Catostomus ardens) during spawning-season sampling and reproductive facilitation in lower Provo River. Suckers are frequently misidentified by these biologists during reproductive surveys that are NATIVE PISCIFAUNA OF UTAH LAKE 3 performed as a part of the June Sucker recovery plan (Charles W. Thompson, personal communication). The temporally-related comparative incidence of the fishes of Utah Lake will be treated in a future paper. Textual and tabular notes of the Utah Lake Fish Management Advisory Team (1994: 16, table 1) indicating that Cope and Yarrow (1876) identified examples of 4 piscine species from Utah Lake, and that 1 of them was Gila nigrescens, are in error. ANNOTATED SYNONYMIES AND DESCRIPTIONS OF TAXA CLASS OSTEICHTHYES ORDER CYPRINIFORMES Family Cyprinidae Leatherside Chub Gila copei (Cope's Gila: Gila is a river near the border of USA and Mexico; copei refers to Professor Edward Drinker Cope, who as a leader of the Wheeler Survey, collected and identified many animals in the western USA in the 1870s). The description of Tigoma gracilis, taken at 41° N latitude (Girard 1857a: 26, c: 166, 206-207, 1858b: 293), has been interpreted (Jordan 1891, Jordan and Evermann 1896a: 236, Jordan et al. 1930: 119, Hayes 1935: 67) to indicate that this form was a synonym. Girard (1858b) did not equate his T. gracilis with Gila gracilis of Baird and Girard (1854a) but Cope and Yarrow (1876: 665) and Jordan (1878a: 424) later did. Jordan (1887b: 818-819) considered G. gracilis and Phoxinus (=Tigoma) gracilis to be separate. Jordan and Evermann (1896a: 227-228) and Jordan et al. (1930: 114) synonymized G. gracilis, which had a short, deep body and dorsal and anal fins bearing 3 rudimentary spiny rays, with Gila robusta. In contrast to G. gracilis, the Leatherside Chub from Utah's Provo and Spanish Fork Rivers had next to the slenderest body (body depth / body length [BD/BL] = 22.4 ± 1.5% [± 1 SD from the mean]; n = 55) and next to the slimmest caudal peduncle (depth = 11.0 ± 0.5% of BL En = 54]; length = 23.3 ± 1.2% of BL = 551) (see Girard 1857a,c, 1858b, Jordan and Gilbert 1882: 238-239, Jouy 1882, and Jordan and Evermann 1896a: 236) of the 6 cyprinids of Utah Lake and its affluents (Hayes 1935: derived from tables 2, 17-20, 22-23, 27-30, 35, 37). Jordan (1891) reported that the 2 types of the vaguely described T. gracilis had been lost; Jordan et al. (1930: 119) noted that this form was unidentifiable. GREAT BASIN NATURALIST 4 There is no evidence to support Jordan's (1887a) report that Platygobio gracilis exists in Salt Lake Basin. Jordan and Gilbert (1881) described examples of Squalius copei from tributaries of Bear River near Evanston, Wyoming, affirming that Hybopsis egregius of Cope (1872a) and Gila egregia of Cope and Yarrow (1876: 662) were synonyms of it but that Tigoma egregia of Girard (1857a: 25, 1858b: 291-292) was not because the number of scales along its lateral line (Su = 66) (see also Jordan 1891; Jordan and Gilbert [1882: 236] indicated that Su = 65) was too low. However, Cope (1872a) had regarded H. egregius and T. egregia as synonymous. Accordingly, Jordan and Gilbert (1882: 238-239) did not include the sketchily described H. egregius as a synonym of S. copei either. Jordan (1887b: 819) regarded Phoxinus (= Tigoma) egregius and Phoxinus (= Squalius) copei as distinct forms. Jordan (1891) excluded Cope and Yarrow's (1876) G. egregia from "Loma, Rio Grande, Colo" as a synonym of Leuciscus copei, while including G. egregia from Utah's Beaver River. Other synonyms of the Leatherside Chub are Alburnellus? sp. from Utah Lake (Cope 1876) and Squalius aliciae (Phoxinus aliciae of Jordan [1887b]) from Utah Lake (Jordan and Gilbert 1882: 238, Jouy 1882) or Provo River near that lake (Jordan and Evermann 1896a: 236, b: 248). Although Jordan and Evermann (1896a) revealed with a list of 3 synonyms that copei had priority (the types of T. gracilis had been lost and gracilis was preoccupied in Leuciscus), they named the species L. aliciae after the wife of a biologist with whom Jordan coauthored a work (Jordan and Jouy 1882) rather than after Cope, but then reversed themselves (Jordan et al. 1930: 119), calling the taxon Cheonda copei. Later, it was referenced as Richardsonius copei (Hayes 1935: 67, Tanner 1936), Snyderichthys copei (Bailey et al. 1960: 17), and finally Gila copei (Sigler and Miller 1963: 74-76, Robins et al. 1991: 20). This species had a rounded snout, equal jaws, and a rather small, low, terminal, and oblique mouth with irregular, uncinate teeth (Jordan and Gilbert 1882: 238-239, Jouy 1882, Jordan and Evermann 1896a: 236, Hayes 1935: 68). Maxillae extended caudad to a point ventrad to the rostral border of the eyes (Girard 1857a: 26, 1858b: 293, Jordan and Gilbert 1882, Jouy 1882, Hayes 1935). Jordan and Evermann's (1896a) statement that maxillae continued slightly beyond that point was not grounded in evidence. The broad head (width f.-- 56-60% of length) had a slightly convex interorbital span which in S. aliciae (Jordan and Gilbert NATIVE PISCIFAUNA OF UTAH LAKE 5 1882, Jouy 1882) = 8.2% of BL, and in R.