Etheostoma lemniscatum Blanton, 2008

Blanton, Rebecca E. & Jenkins, Robert E., 2008, Three new darter species of the Etheostoma percnurum species complex (Percidae, subgenus Catonotus) from the Tennessee and Cumberland river drainages, Zootaxa 1963 (1), pp. 1-24 : 20-22

Etheostoma lemniscatum Blanton , new species

Tuxedo Darter

( Fig. 4d )

Holotype. UF 172576, male 53.8 mm SL, Big South Fork Cumberland River, 1.2 km upstream of the mouth of Troublesome Creek , McCreary County, Kentucky, 8 September 1995, B. Burr.

Paratypes. Cumberland River drainage— Big South Fork system

Kentucky: McCreary County: INHS 102269 (1; 40.0 mm SL), Big South Fork at Blue Heron River access, approximately 6.4 km SW Steams, KY, 20 Sept. 2000, M. Moyer, S. Call, J. Metzmier ; UF 172577 (2; 34.3–51.6 mm SL), taken with holotype ; USNM 394527 (46.1–47.4 mm SL), taken with holotype .

Tennessee: Scott County: ANSP 189239 (2) Big South Fork at mouth of Station Camp Creek , 14.3 km WNW Oneida, 20 May 1972, R. Jenkins, R. Bouchard, D. Etnier, N. Burkhead, Alexander, and Oakerg; NCSM 49702 (3; 23.3–46.3 mm SL), Big South Fork Cumberland River at mouth of Station Camp Creek , at terminus of Station Camp Road (formerly CR 2451), 14.3 air km WNW of Oneida (36.5465° N; 84.665° W), 4 October 1975, W. C Starnes, L. B. Starnes, and J. A. Louton; TU 200493 (2), same locality as ANSP 189239.

Additional Material (nontypes).

Cumberland River drainage—Big South Fork system

Kentucky: McCreary County: SIUC 24761 (1, 1, 1); SIUC 24744 (1, 1, 1); SIUC 24773 (5, 5, 5); SIUC 46940 (1, 1, 1).

Tennessee: Scott County: INHS 83894 (0, 1, 0); SIUC 24739 (1, 1, 1); UT 91.1465 (3, 3, 0); UT 91.4294 (1, 1, 1); UT 91.455 (12, 7, 11).

Diagnosis. Etheostoma lemniscatum is distinguished from all members of the complex by more posteriorpositioned anal fin (B6–B8, =332 vs. 317 or less); pectoral fin of nuptial males with dark, distal band confined to rays of the dorsal half or less of fin (vs. across all rays or all but 1–4 ventral rays); and nuptial males with dark and distinctly defined black bands on the distal margin of the caudal, anal, and second dorsal fins (bands more diffuse in other species). Etheostoma lemniscatum is further distinguished from all members of the complex except E. marmorpinnum by higher modal (44 vs. 43 or less) number of lateral scale rows; and intermediate number of pored lateral line scales (26 or 28 vs. 22 in E. percnurum , and 34 in E. sitikuense ). From E. marmorpinnum and E. percnurum by intermediate percentage of the first dorsal base area covered by scales (60% vs. 100% in E. marmorpinnum and 20% in E. percnurum ); and an intermediate number of scales around caudal peduncle (24 vs. 25 and 23, respectively). From E. marmorpinnum and E. sitikuense by wider distal band on anal fin (50% of fin height vs. 29–39%) and second dorsal fin (25% of fin height vs. 14–16%); and lack of marbling or tessellations in the medial portion of the second dorsal fin of nuptial males. From E. marmorpinnum by lower percentage of belly covered by scales (10% vs. 60–80%); and wider, distal caudal–fin band (18% of fin length vs. 12–15%). From E. percnurum by lower number of caudal-fin rays (16 vs. 18); presence of strong tessellations on medial portion of caudal fin of nuptial males (vs. no tessellations); and narrower distal band on the pectoral fin (range = 14–18% vs. 27–32%). Means of other measurements were also informative for distinguishing E. lemniscatum from members of the complex ( Table 9).

Description. Tables 1–7 provide meristic counts for many variables. Scales below lateral line 7–10 (8, =8.2±0.8); scales above lateral line 6–8 (7, =7.0±0.4); caudal peduncle scale rows below lateral line 10–13 (12, =11.4±0.8); caudal peduncle scales above lateral line 9–12 (10, =10.6±0.8). Cheek, nape, breast, and opercle devoid of scales. Branchiostegal rays 6; gill membranes narrowly to moderately joined. First dorsalfin spines 6–8 (7, =7.1±0.4); second dorsal-fin rays 11–13 (12, =11.9±0.4); pectoral-fin rays 12–14 (13, =12.9±0.4); anal spines 1–2 (2, =1.9±0.3); and anal-fin rays 6–8 (8, =7.4±0.6). Preopercular-mandibular pores 10 (10, =10.0±0.0); infraorbital pores usually 6, rarely 4 (6, =5.9±0.4); anterior infraorbital 4 (4, =4.0±0.0); posterior infraorbital pores usually 2, rarely 0 (2, =2.0±0.2); supraorbital pores usually 4, rarely 5 (4, =4.1±0.3); supratemporal pores 4 (4, =4.0±0.0); left supratemporal pores 2 (2, =2.0±0.0); right supratemporal pores 2 (2, =2.0±0.0).

Measurements for males (nuptial and non-nuptial) and females are presented separately; male measurements are presented in Table 9. Females (n=12): SL 27.4–46.1 (=36.5±6.2); GW 70–80 (=75±5); IOW 40–60 (=47±9); HW 100–120 (=113±7); HL 280–330 (=316±15); P1L 200–280 (=239±21); P2L 180–220 (=198±10); D1H 80–130 (=104±14); D1L 170–210 (=187±12); D2H 130–160 (=135±11); AFH 90–110 (=106±7); CFL 170–220 (=187±14); BW 50–80 (=63±11); H1–H2 100–140 (=113±11); H1–H3 210–240 (=222±10); H1–B4 360–390 (=368±9); H1–H5 110–150 (=136±12); H1–B6 280–320 (=307±12); H2–H5 100–130 (=117±9); H3–B6 150–180 (=168±9); B4–B6 or BD1 150–190 (=164±13); B4–B7 230–280 (=252±16); B4–B8 280–340 (=313±18); B6–B7 300–370 (=342±21); B6–B8 310–380 (=335±23); B7–B8 or BD2 130–150 (=142±9); B7–B9 or D2L 180–230 (=205±12); B7–B10 170–240 (=209±21); B8–B9 200–240 (=218±13); B8–B10 or AFL 130–170 (=146±15); B9–10 100–120 (=108±8); B9–C11 160–190 (=171±10); and B10–C11 190–230 (=204±12).

In-life and preserved coloration and pigmentation of individuals generally as described by Jenkins (1994) for E. percnurum . However, nuptial males with distal bands of pectoral fins narrower (range = 14–18% of fin length), confined to rays on dorsal half of fin; second dorsal (25% of fin height), caudal (18% of fin height), and anal (50% of fin height) fins with dark, distinct, clearly defined distal band; second dorsal without distinct tessellations or marbling, occasionally with light stippling; caudal fin strongly tessellated; tessellations not forming bands. For all individuals: number of transverse bars for males 10–13 (12, =11.9±0.8), for females 10–14 (11 or 12, =11.7±1.0); number of dorsal saddles for males 7–8 (7, =7.2±0.4), for females 7–8 (7, =7.1±0.3); number of caudal stripes for males 3–8 (6, =5.7±1.4), for females rarely 0, usually 4–8 (6, =5.1±1.9); and caudal peduncle with 1 large caudal spot, 2 diffuse spots, or no obvious spot.

Distribution. The Tuxedo Darter occurs in an approximately 19 km mainstem stretch of the Big South Fork Cumberland River, with most individuals observed from the mouth of Station Camp Creek, Scott County, Tennessee, to Bear Creek, McCreary County, Kentucky ( Eisenhour & Burr 2000).

Ecology. The Big South Fork flows through the Cumberland Plateau physiographic region of Tennessee and Kentucky. Where E. lemniscatum occurs, the river is approximately 30–50 m wide and flows through a deep gorge; it is characterized by long, deep pools with large boulders and bedrock substrates, fast, welldefined riffles with cobble, boulders, and gravel, and is completely forested along the mainstem ( Eisenhour & Burr 2000). The species was always observed in silt-free pools or runs with low flow, immediately above riffles where there were cobbles, boulders, and slabrocks ( Eisenhour & Burr 2000). Eisenhour and Burr (2000) provide detailed information on the life history of E. lemniscatum .

It is unclear whether E. lemniscatum is the only species of Catonotus in the mainstem Big South Fork. A single E. flabellare -like specimen, possibly an E. flabellare x E. lemniscatum hybrid, was collected from the River at the mouth of Station Camp Creek in Scott County, Tennessee, 30 July 1993. There are no other known records of E. flabellare in the Big South Fork and additional collecting from this site has not produced additional E. flabellare -like individuals. Eisenhour and Burr (2000) reported eleven other darter species found syntopically with E. lemniscatum : E. baileyi , E. blennioides , Nothonotus camurus , E. caeruleum , E. cinereum , N. sanguifluus , E. stigmaeum , E. tippecanoe , E. zonale , Percina copelandi , and P. caprodes .

Conservation status. Etheostoma lemniscatum was reported as the least common darter observed in the Big South Fork, with an estimated 300–600 individuals in the entire 19 km reach studied by Eisenhour and Burr (2000). The mainstem of the Big South Fork throughout this reach is entirely forested and is protected by the National Park Service, but several tributaries contribute significant sedimentation and other pollutants from mining in their watersheds ( Eisenhour & Burr 2000). The small range of this species and its small population size indicate it requires federal protection and regular monitoring of its habitat and population status. A recovery plan that incorporates these objectives and which is designed to alleviate impacts from mining practices is greatly needed. The extremely limited distribution of this species and its known sensitivity to habitat disturbances indicates that a single event that negatively impacts the population could lead to its extinction. Propagation efforts to bolster numbers may be beneficial to the long-term survival of the species. Translocation outside of its known native range is not recommended.

Etymology. The specific epithet, lemniscatum , means adorned with ribbons referring to the black ribbonlike distal bands of the second dorsal, anal, and caudal fins. The common name, Tuxedo Darter, was suggested by R. Robins after seeing a photograph of a nuptial male, and commenting that it looked like it was ‘dressed for a black-tie affair’.

Figures

FIGURE 4. Nuptial male pigmentation patterns for (A) Etheostoma percnurum, Copper Creek, VA, (B) E. marmorpinnum, Little River–Tennessee drainage, (C) E. sitikuense, Citico Creek, Abrams Creek, and Tellico River–Little Tennessee system, and (D) E. lemniscatum, Big South Fork–Cumberland drainage. Illustrations by J. Sipiorski, 2008.