(Percidae: Etheostoma), with Descriptions of Five New Species

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36 Bulletin 30 NOVEMBER 1, 2012palatine teeth present (vs. palatine teeth present in only33 % of specimens), modally 11 dorsal spines (vs. 12),modally 4–5 scales above the lateral line (vs. 6), and modally15 principal caudal rays (vs. 16–17). Although manyaspects of breeding coloration are similar, E. stigmaeumdiffers further from E. meadiae in having blue-green pigmenton the mid-gular region.Etheostoma stigmaeum differs from E. obama, E. gore, andE. jimmycarter in having modally 11 dorsal spines (vs. 12–13) and palatine teeth usually present (vs. usually absentor present in only 29% of specimens). Breeding males ofE. stigmaeum differ from those of the other three speciesin having soft dorsal, caudal, and pectoral fins lacking orangespots, the base of the spinous dorsal fin lacking orangepigment, the base color of the face and underside ofhead gray (vs. tangerine orange), and the lateral blotchesvertically elongate (vs. quadrate).Etheostoma clinton is distinguished from all other speciesof Doration by having 9 preoperculomandibular pores (vs.10 in all other species), smallest maximum adult size (40 mm SL), and breeding males having anarrow midlateral band of melanophores connecting theseries of blue-green blotches. It is most similar to E. stigmaeumin overall appearance but differs further from thatspecies in having modally 9 anal soft rays (vs. 8), modally13–14 pectoral rays (vs. 14), usually naked or nearly nakedcheeks (vs. usually partly scaled), and a higher meancount of lateral scales (49.9 vs. 46.4).Etheostoma teddyroosevelt is similar to E. obama, E. gore, andE. jimmycarter in that breeding males have distinct orangespots on the second dorsal, caudal, and anal fins; however,in E. teddyroosevelt they are more subdued and occasionallyobscured by melanophores. Etheostoma teddyroosevelt differsfrom these three species in having breeding males lackingorange pigment in the base of the spinous dorsal finand having the base color of the face gray (vs. tangerineorange), and in having modally 7 scales below the lateralline (vs. 6). It differs further from E. obama and E. gorein breeding males having black marginal and submedialbands in the spinous dorsal fin (vs. blue), soft dorsal andanal fins lacking blue pigment, and the basicaudal bluebar mainly developed ventrally. It differs further from E.jimmycarter in having modally 14 pectoral rays (vs. 15), ahigher mean count of lateral scales (48.1 vs. 45.4), andbreeding males with a solid black submedial black band(vs. interrupted with vertical orange streaks).Etheostoma teddyroosevelt differs from E. stigmaeum and E.clinton in breeding males having black marginal and submedialbands in the spinous dorsal fin (vs. blue-green),deep blue lateral blotches (vs. blue-green), orange spotson the soft dorsal, caudal, and anal fins (vs. lacking), andin lacking blue pigment on the lips and mid-gular region(vs. present). It differs further from these two species inusually lacking palatine teeth (although present in up to29% of upper White River specimens) and having a morecompletely and consistently scaled nape. Etheostoma teddyrooseveltdiffers further from E. clinton in having a fullyscaled belly (vs. incompletely scaled anteriorly) and differsfurther from E. stigmaeum in having usually naked cheeks(vs. partly scaled).Principal component analysis of 17 meristic variablesin 3,049 specimens shows a high degree of overlap amongthe nine species of Doration (Fig. 21). This, in part, illustrateswhy the systematics of the group has been so poorlyunderstood without fuller knowledge of breeding colorvariation. The analysis does not incorporate data on thefrenum or palatine teeth, characters that are also usefulin distinguishing species. Etheostoma stigmaeum, the geographicallymost widespread species, encompasses thegreatest amount of meristic variation, both along principalcomponent one (PC-I) and PC-II (Fig. 21). The PC-Iaxis provides nearly complete separation between E. jessiaeand E. akatulo. Variables loading most heavily on PC-Iinclude transverse scales, caudal peduncle scales, scalesabove and below the lateral line, and lateral scales (Table14). Other variables loading heavily are several fin raycounts and opercle, nape, and cheek squamation. The PC-II axis provides little distinction between species from theTennessee (E. jessiae, E. meadiae, E. obama), Cumberland(E. akatulo and E. gore), and Green (E. jimmycarter) riverdrainages but largley polarizes this group from E. clinton(Fig. 21). The plot completely separates both E. jessiaeand E. akatulo from E. clinton. Variables with the highestloadings on PC-II are nape and belly squamation (Table14). Others loading heavily include scales below the lateralline, unpored lateral scales, anal fin rays, pectoral finrays, transverse scales, dorsal fin spines, and cheek squamation.The greatest overlap occurs between E. meadiae,E. obama, E. gore, and E. jimmycarter (Fig. 21).Morphometrics.—Comparison of proportional measurementsin Table 12 and in Layman and Mayden (2009)reveals that E. jessiae has a longer snout than any other speciesof Doration. In addition, E. jessiae has relatively greaterhead length, predorsal length, upper jaw length, and softdorsal fin base length than most other species. Etheostomameadiae has a moderate snout but shares with E. jessiae arelatively long head, predorsum, and upper jaw. It differsfrom E. jessiae and most other species in having a deeperbody at the spinous and soft dorsal fin origins, deeper andshorter caudal peduncle, wider body, and greater analspine length. Etheostoma stigmaeum from the Coosa Riveralso has a moderately produced snout, long upper jaw,deep body at the soft dorsal fin origin, and deep caudalpeduncle. Etheostoma teddyroosevelt is also relatively robust,with greater body width and body depth at the spinousdorsal fin origin than all other species except E. meadiae.Etheostoma obama has proportionally larger fins thanmost other species of Doration as indicated by mean measurementsof spinous dorsal fin origin to soft dorsal fin origin,dorsal spine length, soft dorsal fin base length, analfin base length, and pectoral and pelvic fin lengths (Table12; Layman and Mayden, 2009: table 1). Etheostoma gore has
Layman & Mayden Morphological Diversity and Phylogenetics of the Darter subgenus Doration (Percidae: Etheostoma) 37arates E. meadiae and E. akatulo (Fig. 22A). In addition,E. clinton separates almost completely from E. stigmaeumof the Ouachita River (Fig. 22B); these samples are fromgeographically close localities in the Ouachita River systemabove and below the Fall Line, respectively. Amongpopulations of E. stigmaeum, the least overlap occurs betweenthe Ouachita and Coosa rivers, the geographicallymost distant samples (Fig. 22B).The plot of sheared PC-II versus sheared PC-III forfemale measurements (Fig. 23, Table 15) reveals similartrends in shape differentiation as observed in males, withE. jessiae completely separated from E. meadiae, E. obama,Figure 21. Plot of meristic principal component one(PC-1) and PC-II for nine species of Doration. Polygonsbound all individuals of: 1—Etheostoma stigmaeum;2—E. jessiae; 3—E. meadiae; 4—E. akatulo; 5—E. obama;6—E. gore; 7—E. jimmycarter; 8—E. teddyroosevelt; 9—E.clinton.a large spinous dorsal fin, and it and E. jimmycarter haverelatively long pectoral and pelvic fins. Etheostoma akatulois a slender species of Doration with a moderate snout,narrow body depth at the spinous dorsal fin origin, longand narrow caudal peduncle, narrow trans-pelvic width,and short pectoral and pelvic fins. Within Doration, the diminutiveE. clinton has the shortest snout, narrowest bodydepth at the spinous and soft dorsal fin origins, shortestdistance between the spinous and soft dorsal fin origins,narrowest trans-pelvic width, and narrowest body.Sheared principal component analysis of 28 morphometricvariables reveals substantial overlap among malesof species of Doration in overall body form and fin size, butseveral species can be distinguished from one another onthis basis. The plot of sheared PC-II against sheared PC-IIIcompletely or nearly completely separates E. jessiae fromall other species except E. akatulo, with which it overlapsonly moderately (Fig. 22A). Most notably, E. jessiae separatescompletely from E. meadiae and E. obama, parapatricneighbors in the Tennessee River drainage. All or most ofthis separation occurs along sheared PC-II. Variables loadingheavily on this axis are first anal spine length, snoutlength, and distance from the midline at least interorbitalwidth to the snout (Table 15). Nearly complete separationis also obtained between E. meadiae and E. stigmaeum fromthe Coosa River along sheared PC-II (Fig. 22A). ShearedPC-III completely separates E. teddyroosevelt from all otherspecies except E. stigmaeum (Fig. 22A). Variables accountingfor the most variance on this axis include three bodydepth measurements, first anal spine length, anal fin baselength, and snout length (Table 15). The plot nearly sep-Figure 22. Plot of morphometric sheared principalcomponent two (PC-II) and sheared PC-III for males ofnine species of Doration. (A) and (B) are the same buthighlight different sets of polygons to facilitate interpretation.Polygons bound all individuals of: 1—Etheostomastigmaeum, Coosa River (Mobile Basin); 2—E. stigmaeum,Pearl River (central Gulf Coast); 3—E. stigmaeum,Clarks River (upper Mississippi Embayment); 4—E. stigmaeum,Ouachita River (lower Mississippi Embayment);5—E. jessiae; 6—E. meadiae; 7—E. akatulo; 8—E. obama;9—E. gore; 10—E. jimmycarter; 11—E. teddyroosevelt;12—E. clinton.
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