Zootaxa, Crystallaria cincotta, a new species of darter (Teleostei ...

Zootaxa 1680: 62–68 (2008)www.mapress.com/zootaxa/Copyright © 2008 · Magnolia PressISSN 1175-5326 (print edition)ZOOTAXAISSN 1175-5334 (online edition)Crystallaria cincotta, a new species of darter (Teleostei: Percidae) from the ElkRiver of the Ohio River drainage, West VirginiaSTUART A. WELSH 1 & ROBERT M. WOOD 21U.S. Geological Survey, West Virginia Cooperative Fish and Wildlife Research Unit, 322 Percival Hall, Morgantown, WV 26506–6125, USA. E-mail: swelsh@wvu.edu2Department of Biology, Saint Louis University, 3507 Laclede, St. Louis, MO 63103–2010, USA. E-mail: wood2@slu.eduAbstractA new species of percid, Crystallaria cincotta, is described from the Cumberland, Elk, Green, and Muskingum riverdrainages of the Ohio River basin, USA. It differs from populations of Crystallaria asprella of the Gulf Coast, lowerMississippi River, middle Mississippi River, upper Mississippi River, and Wabash River drainages by having a reducednumber of cheek scale rows restricted to the post-orbital region, a falcate margin on the pelvic fins, a preorbital blotchdistinctly separate from the anterior orbital rim, and a wide mouth gape. The Elk River population is also divergentgenetically from populations of the Gulf Coast, lower Mississippi River, and upper Mississippi River drainages. Crystallariacincotta, discovered in the Elk River of the Ohio River drainage in 1980, is a rare species with the only extant populationrepresented by 12 individuals collected from 1980–2005 from the lower 36 km section of the Elk River, WestVirginia.Key words: new species, darter, Percidae, Crystallaria, Elk RiverIntroductionCrystallaria asprella (Jordan), the crystal darter, was recognized as the sole member of a monotypic genus(Simons 1991). The crystal darter has a wide and fragmented geographic distribution within the MississippiRiver system (Page 1983), including population segments in the Gulf Coast, lower Mississippi River, middleMississippi River, and upper Mississippi River (Morrison et al. 2006). Museum specimens from the Cumberland,Green, Muskingum, and Wabash rivers support a previous wide-spread distribution of Crystallariawithin the Ohio River drainage. A population in the Elk River, WV (Ohio River drainage) was discovered in1980 (Cincotta and Hoeft 1987). A total of 12 individuals have been collected from Elk River during 1980–2005. Genetic diversity of Crystallaria was examined at the mitochondrial cytochrome b gene (Wood andRaley 2000) and at two additional loci; the mitochondrial control region, and an intron of the nuclear S7 ribosomalprotein (Morrison et al. 2006). Wood and Raley (2000) and Morrison et al. (2006) both reported thatthe Elk River population was genetically divergent from the Gulf Coast, lower Mississippi River, and upperMississippi River populations. Our objective is to provide morphologic data to supplement the genetic evidencein support of the new species status of the extant Elk River population of Crystallaria.Material and methodsIn addition to the genetic data of Wood and Raley (2000) and Morrison et al. (2006), this study is based on62Accepted by L. Page: 6 Dec. 2007; published: 14 Jan. 2008

Mississippi. MMNS 28727 (30, 64–106) Itawamba Co., East Fork of Tombigbee River, 19 Sept. 2001.Arkansas. NLU 48454 (11, 75–90) Bradley Co., Saline River, 26 Sept. 1981. NLU 48646 (15, 72–88)Bradley Co., Saline River, 17 Oct. 1981. MMNS 32293 (3, 68–72) Lawrence Co., Strawberry River, 23 May1991.Crystallaria cincotta, new speciesDiamond DarterFig. 2, Table 1Holotype. UMMZ 233255, 73 mm SL, West Virginia, Kanawha Co., Elk River,1.6 km upstream of mouth ofBig Sandy Creek, Clendenin, WV, 18 July 1991, D.A. Cincotta, M.E. Hoeft, and S.F. Morrison.Paratypes. West Virginia. USMF (Frostburg State University, Frostburg, MD) 200616 (1, 73 mm SL)taken with holotype. USMF 200617 (1, 76), Kanawha Co., Elk River, 1.6 km upstream of mouth of Big SandyCreek, Clendenin, WV, 25 Aug 1999. USMF 200618 (2, 75–76) Kanawha Co., Elk River, 150 m downstreamof mouth of Big Sandy Creek, Clendenin, WV, 29 Aug. 2003. USMF 200619 (2, 76–77) Kanawha Co., ElkRiver, 150 m downstream of mouth of Big Sandy Creek, Clendenin, WV, 8 July 2005.Additional material (nontypes).Ohio. OSUM 8996 (1, 72 mm SL) Washington Co., Muskingum River, 31 Aug. 1888. OSUM 9688 (1,51) Lawrence Co., Ohio River, 31 May 1899. Kentucky. USNM 63786 (1, 77) Green Co., Green River, 1890.USNM 89467 (2, 37–49) Edmonson Co., Green River, 31 Aug. 1929. FMNH 6825 (1, 67) Lyon Co., CumberlandRiver, date unknown.Diagnosis. A species of Crystallaria that differs from populations of C. asprella of the Gulf Coast, lowerMississippi River, middle Mississippi River, upper Mississippi River, and Wabash River by a combination ofthe following characters: a larger gape width approximately equal to or exceeding the inter-pelvic fin basewidth, a preorbital blotch distinctly separate from the anterior orbital rim, pelvic fins distinctly falcate in bothsexes, cheek scale rows reduced (modally 2), opercle scale rows reduced (modally 2), a high count of mid-lateralblotches (modally 13), a low count of anal-fin rays (modally 13), a low count of dorsal-fin spines (modally12), and a high count of scales below the lateral line (modally 11).FIGURE 2. Crystallaria cincotta, 75 mm SL male, Elk River, West Virginia.Description. Morphometric measurements (as percentage of SL) are given in Table 1. Dorsal-fin spines(11–13, modally 12), dorsal-fin rays (11–15, modally 13), anal-fin rays (11–13, modally 13), principal caudalrays (17), lateral-line scales (83–93, modally 87), cheek scale rows restricted to the post-orbital region (1–4,modally 2), opercle scale rows (1-4, modally 2), mid-lateral blotches (12–14, modally 13), breast and bellywithout scales, gape width approximately equal to or greater than inter-pelvic fin width. Pelvic fins with falcateposterior margin. Preorbital blotch distinctly separate from the anterior orbital rim.64 · Zootaxa 1680 © 2008 Magnolia PressWELSH & WOOD

TABLE 1. Morphometric data from a box-truss network of measurements for the holotype and paratypes of Crystallariacincotta. Distance measurements are presented as thousandths of standard length.Paratypes (n=6)Distances Holotype Mean SD RangeStandard length (mm) 73.3 75.4 1.5 73.0–77.3Snout–occiput 215.4 211.9 4.8 206–218Occiput–first dorsal-fin spine 141.3 146.7 7.3 136–158Base of fist dorsal fin 283.6 287.5 14.7 273–309Base of second dorsal fin 137.0 156.0 15.0 139–181Last dorsal-fin ray–dorsal caudal flexure 262.9 265.4 16.2 239–281Depth at caudal flexure 84.6 82.5 4.6 76–89Last anal-fin ray–ventral caudal flexure 241.3 242.8 10.9 228–255Base of anal fin 182.9 182.8 7.1 172–193Mid-point between pelvic-fin bases–first anal-fin ray 300.3 305.5 9.5 295–322Branchiostegal connection–midpoint between pelvic-fin bases 200.7 200.6 6.3 191–207Snout–branchiostegal connection 136.4 131.6 11.3 114–144Branchiostegal connection–occiput 171.9 148.1 8.0 138–162Branchiostegal connection–first dorsal-fin spine 260.0 250.4 8.3 238–261Occiput–mid-point between pelvic-fin bases 155.4 172.7 11.9 155–192Mid-point between pelvic-fin bases–first dorsal-fin spine 113.1 127.1 14.2 111–152Mid-point between pelvic-fin bases–second dorsal-fin insertion 356.9 331.8 17.6 313–361First dorsal-fin spine–anal-fin insertion 291.8 296.4 10.3 285–310Anal-fin insertion–second dorsal-fin insertion 105.3 109.7 2.8 106–114Anal-fin insertion–last dorsal-fin ray 190.7 177.5 13.1 162–195Second dorsal-fin insertion–last anal-fin ray 177.6 188.0 6.7 180–199Last dorsal-fin ray–last anal-fin ray 68.9 76.6 6.2 69–84Last anal-fin ray–dorsal caudal flexure 255.9 252.5 16.2 233–280Last dorsal-fin ray–ventral caudal flexure 259.6 273.0 7.8 265–286Snout–anterior margin of eye 87.0 91.0 2.7 88–94Eye width 77.5 75.3 3.7 71–82Snout–opercle spine tip 257.2 262.3 5.7 255–271Anterior internasal width 42.2 49.6 2.0 46–52Posterior internasal width 55.4 57.9 2.3 56–62Interorbital width 33.8 30.7 1.4 30–33Gape width 84.6 81.0 4.6 76–88Interpelvic base width 73.4 74.4 3.1 70–77Body is overall translucent. Olive brown melanophores are concentrated as four wide saddles on the backand dorsal sides. Saddles angle anteriad on dorsal sides and are outlined with anterior and posterior dark margins.Between the saddles, olive brown melanophores on scale margins produce a fragmented cross-hatch pattern.The ventral sides of the body and head are silvery white. A preorbital blotch is dark and distinctlyseparated from the anterior margin of the orbital rim. The mid-lateral pigmentation includes 12–14 oblongolive-brown blotches overlain by an iridescent olive green stripe. Fins are clear with the exception of sparsepigmentation on the caudal fin.CRYSTALLARIA CINCOTTA, A NEW SPECIES OF DARTERZootaxa 1680 © 2008 Magnolia Press · 65

Comparisons. Crystallaria cincotta differs from populations of C. asprella of the Gulf Coast, lower MississippiRiver, middle Mississippi River, upper Mississippi River, and Wabash River by a combination of thefollowing characters: gape width approximately equal to or exceeding the inter-pelvic fin base width (gapewidth 7.3–8.6% SL vs. 3.7–6.1), preorbital blotch distinctly separate from anterior orbital rim vs. preorbitalblotch adjoined to or narrowly separate from anterior orbital rim, and pelvic fins distinctly falcate vs. pelvicfins not falcate. Additionally, a combination of the following meristic characters separate C. cincotta from C.asprella; cheek scale rows reduced (1–4, modally 2 vs. 4–14, modally 11), opercle scale rows reduced (1–4,modally 2 vs. 2–13, modally 4), a higher modal count of mid-lateral blotches (12–14, modally 13 vs. 8–14,modally 10), a lower count of anal-fin rays (11–13, modally 13 vs. 12–16, modally 14), a lower count of dorsal-finspines (11–13, modally 12 vs. 10–17, modally 14), a higher count of scales below the lateral line (10–14, modally 11 vs. 7–14, modally 9, Table 2). Additionally, C. cincotta differs from the Gulf, lower Mississippi,and upper Mississippi populations of C. asprella by cytochrome b sequence divergence (11.31, 11.95,and 11.84%; Wood and Raley 2000), and net nucleotide divergences of the mitochondrial control region (4.97,5.25, and 4.39%) and the nuclear S7 intron (2.25, 2.03, and 2.04%; Morrison et al. 2006). Genetic evidencesupports the species recognition of C. cincotta. Genetic divergence values of Crystallaria in the Elk River areconsistent with divergence values of interspecific or intergeneric divergence (Wood and Raley 2000).TABLE 2. Meristic data for Crystallaria asprella and Crystallaria cincotta.Crystallaria asprella (N=96) mode (range) Crystallaria cincotta (N=13) mode (range)Anal-fin rays 14 (12–16) 13 (11–13)Dorsal-fin rays 13 (11–15) 13 (11–15)Dorsal-fin spines 14 (10–17) 12 (11–13)Pectoral-fin rays 16 (15–19) 16 (15–17)Lateral-line scales 89 (77–96) 87 (83–93)Scales above lateral line 8 (6–10) 8 (7–9)Scales below lateral line 9 (7–14) 11 (10–14)Cheek scale rows 11 (4–14) 2 (1–4)Opercle scale rows 4 (2–13) 2 (1–4)Mid-lateral blotches 10 (8–14) 13 (12–14)In a plot of sheared PC2 by sheared PC3, gape width (-0.71) loaded highest on the sheared PC2 axis (Fig.3). Measurements associated with the posterior region loaded highest for sheared PC3; last ray of second dorsalfin to dorsal caudal flexure (0.30), last ray of second dorsal fin to ventral caudal flexure (0.28), base of analfin (-0.30), base of second dorsal fin (-0.32), last ray of anal fin to dorsal caudal flexure (0.20), last ray of analfin to second dorsal fin insertion (-0.22), anal-fin insertion to last ray of second dorsal fin (-0.34). Individualswith high sheared PC3 scores had longer caudal peduncle regions owing to fewer rays in the second dorsaland anal fins, but most populations overlapped along this axis (Fig. 3).Conservation status. Crystallaria cincotta is extirpated from most of its former range within the OhioRiver drainage, and is known only to be extant in the Elk River, West Virginia. Wood and Raley (2000) suggestedthat the population of Crystallaria in Elk River, West Virginia, should be given federal protectionunder the U.S. Endangered Species Act based on the scarcity of individuals, the genetic uniqueness and sistergroup relationship with C. asprella, and cumulative landuse threats within the Elk River drainage. The scarcityof C. cincotta in the Elk River is supported by a total of 12 specimens from extensive sampling effortsfrom 1980 to 2005. Most collections of C. cincotta have occurred in moderate flows over a sand, gravel, andcobble mix of benthic substrate within lower sections of riffles or upper sections of pools (Osier 2005). This66 · Zootaxa 1680 © 2008 Magnolia PressWELSH & WOOD

type of river habitat is vulnerable to substrate embeddedness from siltation, and we have observed large yearto-yearchanges in substrate embeddedness within the lower Elk River. Grandmaison et al. (2003) reportedsiltation from current landuse practices as a major concern for conservation of Crystallaria in the Elk Riverdrainage.FIGURE 3. Sheared PC2 by sheared PC3 scatter plot of Crystallaria asprella from the Gulf Slope (open squares), lowerMississippi River (open triangles), middle Mississippi River (open diamonds), upper Mississippi River (open circles),and Wabash River (plus signs), and Crystallaria cincotta from the Cumberland River (solid triangle), Elk River (soliddiamonds), Green River (solid circle), and Muskingum River (solid square).Etymology. The name cincotta is in recognition of Daniel A. Cincotta, fishery biologist for the West VirginiaDivision of Natural Resources, and adjunct professor of ichthyology, West Virginia University. He hasdevoted a 30 year career toward studies of the diversity of West Virginia fishes, including efforts toward conservationof the Elk River drainage and its diverse ichthyofauna. The common name, Diamond Darter, is inreference to the sparkle from reflected light when viewed with lights during nighttime collections, and alsofits the analogy of a diamond as a rare crystal.Remarks. Given that populations of Crystallaria have been extirpated from many localities within theirrange, it is difficult to draw precise boundaries around the historical distributions of the two component species.Populations of Crystallaria are considered extirpated in the states of Ohio, Indiana, Illinois, Tennessee,Kentucky and Iowa (Wood and Raley 2000). While these populations would likely unambiguously assign toone species or the other given availability of museum specimens, without specimens it is difficult to assess thefull historical range of either species with any confidence. Presumed extirpated populations of particular interestthat we can comment on include those from the Wabash River in Indiana, the lower Cumberland River inKentucky, the Green River in Kentucky, and the Muskingum River in Ohio. In these cases, the availability ofmuseum specimens allow us to unambiguously assign the populations from the Cumberland, Green, andMuskingum to C. cincotta and the Wabash population to C. asprella based on the diagnostic morphologicalcharacters discussed above. We infer that C. cincotta was broadly distributed throughout the Ohio River basinexclusive of populations in the Wabash River in Indiana. These latter populations are referred to C. asprellawhich is hypothesized to have ranged broadly throughout the Mississippi River basin, the Gulf Coast drainages,and the Wabash River drainage. The assignment of most of the extirpated populations is problematic dueCRYSTALLARIA CINCOTTA, A NEW SPECIES OF DARTERZootaxa 1680 © 2008 Magnolia Press · 67

to the absence of museum specimens for analysis and an incomplete understanding of the complex drainagehistory of North America.AcknowledgementsWe are grateful to the following for access to museum specimens: Hank Bart (TU), Andy Bentley and EdWiley (KU), Neil Douglas (NLU), Mark Dugo (MMNS), Marc Kibbey and Ted Cavender (OSUM), BernieKuhadja (UAIC), Jerry Finan (USNM), Doug Nelson (UMMZ), Andrew Simons (JFBM), and Mark Westneat(FMNH). Reference to trade names does not imply government endorsement of commercial products.Literature citedBookstein, F.L., Chernoff, B., Elder, R.L., Humphries, J.M., Smith, G.R. & Strauss, R.E. (1985) Morphometrics in evolutionarybiology. Academy of Natural Sciences, Philadelphia, Special publication, 15, 1–277.Cincotta, D.A. & Hoeft, M.E. (1987) Rediscovery of the crystal darter, Ammocrypta asprella, in the Ohio River basin.Brimleyana, 13, 133–136.Grandmaison, D., Mayasich, J. & Etnier, D. (2003) Crystal darter status assessment report. NRRI Technical Report No.NRRI/TR-2003/19.Humphries, J.M., Bookstein, F.L., Chernoff, B., Smith, G.R., Elder, R.L. & Poss, S.G. (1981) Multivariate discriminationby shape in relation to size. Systematic Zoology, 30, 291–308.Morrison, C.L., Lemarie, D.P., Wood, R.M. & King, T.L. (2006) Phylogeographic analyses suggest multiple lineages ofCrystallaria asprella (Percidae: Etheostominae). Conservation Genetics, 7, 129–147.Osier, E.A. (2005) Distribution and habitat use of the crystal darter (Crystallaria asprella) and spotted darter (Etheostomamaculatum) in the Elk River, West Virginia. M.S. Thesis, West Virginia University, Morgantown, West Virginia.Page, L.M. (1983) Handbook of Darters. T.F.H. Publications, Neptune City, New Jersey, 271 pp.Simons, A.M. (1991) Phylogenetic relationships of the crystal darter, Crystallaria asprella (Telostei: Percidae). Copeia,1991, 927–936.Strauss, R.E. & Bookstein, F.L. (1982) The truss: body form reconstruction in morphometrics. Systematic Zoology, 31,113–135.Wood, R.M. & Raley, M.E (2000) Cytochrome b sequence variation in the crystal darter Crystallaria asprella (Actinopterygii:Percidae). Copeia, 2000, 20–26.68 · Zootaxa 1680 © 2008 Magnolia PressWELSH & WOOD