Patera nantahala (Clench & Banks, 1932)

Whelan, Nathan V., Strong, Ellen E., Gladstone, Nicholas S. & Mays, Jason W., 2023, Using genomics, morphometrics, and environmental niche modeling to test the validity of a narrow-range endemic snail, Patera nantahala (Gastropoda, Polygyridae), ZooKeys 1158, pp. 91-120 : 91

Patera nantahala (Clench & Banks, 1932)

Polygyra (Triodopsis) nantahala Clench & Banks, 1932: 17, pl. 2, figs 1-3, 5.

Mesodon clarki nantahala - Pilsbry 1940: 731, fig. 440g; Chambers 1981: 55-59; Hubricht 1983: 13; Hubricht 1985: 44; Richardson 1986: 45.

Patera clarki nantahalae [sic]- Emberton 1995: 72.

Type material.

Holotype: MCZ 86429. GS Banks leg., 27 August 1930.

Paratypes: ANSP 153664 (4 spms), GS Banks leg., 25 August 1930; MCZ 82533 (1 spm), Clench, Archer & Rehder leg., 7 August 1931; MCZ 185877 (3 spms), Clench, Rehder & Archer leg., July 1931, ex. A Archer collection; USNM 408310 (3 spms), Clench, Rehder & Archer leg., 1931.

Type locality.

Blowing Springs, cliff ridges, Nantahala Gorge, Swain County, North Carolina.

Other material examined.

USNM 1522409, USNM 1522410: Adjacent to unnamed tributary of Nantahala River , southeast cliff of Nantahala Gorge, Swain County, North Carolina , 35.308, -83.644, GenBank : OQ617122, OQ628062, OQ628460, OQ617123, OQ628056, OQ628461 , SRA: SRX19664333, SRX19664332; USNM 1522411: Adjacent to Pizza by the River , northeast corner of Nantahala Gorge , Swain County , North Carolina , 35.336, -83.620, GenBank : OQ617124, OQ628055, OQ628462 , SRA: SRX19664329 ANSP 171736: Blowing Springs , Swain County , North Carolina ; ANSP 348077: Nantahala Gorge , Swain County , North Carolina , 35.40, -83.25; MCZ 94130 : Blowing Springs , Nantahala Gorge , Swain County , North Carolina .

Diagnosis.

Shell imperforate, subglobose, weakly translucent, with 5.5-5.75 whorls. Teleoconch sculpture of coarse, prosocline, axial striae. Spire low, dome-shaped, sutures weakly impressed. Aperture lunate, peristome white, with small basal notch. Slightly curved parietal tooth, moderate in size for the genus. Mantle pigmentation of branching lines in at least some individuals.

Distribution.

Restricted to the eastern slope of the Nantahala Gorge in North Carolina, USA.

Ecology.

Little is known about the ecology of P. nantahala . The species appears to prefer the moist, highly vegetated habitats that receive little sunlight, which are typical of the eastern slope of the Nantahala Gorge. Found only in habitats with soil characterized by the SSURGO soil map as "Inceptisols: Sylco-Cataska complex, 50 to 95 percent slopes, very rocky".

Conservation status.

Federally threatened under the U.S. Endangered Species Act. Listed as threatened by the state of North Carolina. Available data indicate that P. nantahala is in one of the three “threatened” IUCN ranking categories, likely falling under “endangered”.

Remarks.

All sampled P. nantahala individuals are more similar to the holotype and paratypes of P. nantahala than to the types of P. clarkii . Shell shape of P. nantahala differs significantly from closely related lineages (Figs 2 - 5 ; Table 3 ). We are unable to comment on internal anatomical variation among P. aff. clarkii lineages and P. nantahala because we did not preserve specimens in a manner suitable for anatomical work. Emberton (1995) examined internal anatomy of Patera and found no differences among P. clarkii , P. perigrapta , and other species in the subgenus Patera (Patera) , making it unlikely that anatomical investigations would yield diagnosable features among the lineages examined here.

Figures

Figure 2. Photographs of type specimens A holotype of Patera nantahala, MCZ 86429 B syntype of Patera clarkii, MCZ 93923. Scale bar: 1 cm.

Figure 5. Landmarks used for geometric morphometrics and history of canonical variate scores. Shells are type specimens and points represent landmarks connected by wireframe that shows shape variation. Wireframe graphs under CVA plots represent extremes and show shape changes associated with canonical variates.