Nesticus cherokeensis, Hedin & Milne, 2023

Hedin, Marshal & Milne, Marc A., 2023, New species in old mountains: integrative taxonomy reveals ten new species and extensive short-range endemism in Nesticus spiders (Araneae, Nesticidae) from the southern Appalachian Mountains, ZooKeys 1145, pp. 1-130 : 1

Nesticus cherokeensis sp. nov.

Figs 16A-F , 17A-H

Material examined.

Type material: Holotype: USA - North Carolina, Swain Co. • ♂; Blue Ridge Parkway, below Ballhoot Scar overlook near Ravensford ; 35.5167°N, - 83.2837°W; 9 Aug. 1992; M. Hedin leg.; (MCH specimen #1177) . Paratypes: - North Carolina, Swain Co. • ♂, 10♀; Blue Ridge Parkway, below Ballhoot Scar overlook near Ravensford ; 35.5167°N, - 83.2837°W; 9 Aug. 1992; M. Hedin leg.; (MCH specimens #1176, #1178-1187) . Non type material : - North Carolina, Haywood Co. • 2♂, 3♀; Dogwood Flats Creek, W Longarm Mountain ; 35.7201°N, - 83.0731°W; 18 Aug. 2001; M. Hedin, M. Lowder leg. ; MCH 01_135; • ♂, 12♀; Flat Branch Creek of Mt Sterling Creek, south of Waterville ; 35.7407°N, - 83.0741°W; 18 Aug. 2001; M. Hedin, M. Lowder leg. ; MCH 01_134; • 2♀; Flat Branch Rd, SE Mt. Sterling, along Laurel Creek ; 35.7526°N, - 83.0895°W; 12 Aug. 2004; M. Hedin, R. Keith, J. Starrett, S. Thomas leg. ; MCH 04_046; • ♂, 3♀; FR 288 above Pigeon River ; 35.726°N, - 83.0265°W; 18 Aug. 2001; M. Hedin, M. Lowder leg. ; MCH 01_136; • ♀; FR 288 along Pigeon River , 0.4 mi. SW of I-40; 35.7308°N, - 83.025°W; 27 Aug. 2005; M. Hedin, R. Keith, J. Starrett, S. Thomas leg. ; MCH 05_094; • ♀, 4 imm; Great Smoky Mountains NP, Big Creek, 100 yards up Baxter Creek trail from picnic area; 35.7506°N, - 83.1088°W; 17 Oct. 1994; F. Coyle leg. ; • 3♀, 6 imm; Great Smoky Mountains NP, Boogerman Trail 0.5 mi from Northern end, N extension Den Ridge ; 35.6225°N, - 83.0847°W; 11 Sep. 1994; F. Coyle, J Miller leg. ; • ♀; Great Smoky Mountains NP, Cataloochee area, Sag Branch , 1.5 mi from N end Caldwell Fork Trail ; 35.6435°N, - 83.0766°W; 10 Sep. 1994; F. Coyle, J Miller leg. ; • ♂; Great Smoky Mountains NP, Cataloochee, 150 meters S mouth Palmer Branch at Caldwell Fork ; 35.6251°N, - 83.1121°W; 4 Jun. 1996; F. Coyle, Edwards, Stiles, Wright leg. ; - North Carolina, Jackson Co. • ♂, ♀; Blue Ridge Parkway, Mile 460, near Bunches Bald Tunnel ; 35.5092°N, - 83.1883°W; 9 Aug. 1992; M. Hedin leg. ; - North Carolina, Swain Co. • ♂, ♀; Great Smoky Mountains NP, 0.25 mi. NW Hientooga Overlook / Picnic Area on Hientooga Round Bottom Road ; 35.5748°N, - 83.1805°W; 3 Sep. 2002; M. Hedin, M. Lowder, P. Paquin leg. ; MCH 02_186; • ♂, 4♀, 1 imm; Great Smoky Mountains NP, road to Balsam Mountain, N Black Camp Gap ; 35.5437°N, - 83.1679°W; 3 Sep. 2002; M. Hedin, M. Lowder, P. Paquin leg. ; MCH 02_185; • ♂, ♀; Wesser Creek, Dills Road , S of Whittier; 35.3953°N, - 83.3746°W; 18 Aug. 2007; M. Hedin, M. McCormack, S. Derkarabetian leg. ; MCH 07_118; - Tennessee, Cocke Co. • ♂, 5♀; Great Smoky Mountains NP, above Cosby CG on Snake Den Ridge trail; 35.7432°N, - 83.2218°W; 1 Aug. 1995; F. Coyle, Carbiener leg. ; • ♀; Great Smoky Mountains NP, Cosby Ranger Station along Cosby Creek , behind ATBI residence house; 35.7779°N, - 83.2135°W; 28 Jul. 2000; M. Hedin, J. Cokendolpher leg. ; MCH 00_138; • ♂; Great Smoky Mountains NP, Maddron Bald trail to Albright Grove ; 35.7608°N, - 83.271°W; 3 Aug. 2000; M. Hedin, W. Reeves leg. ; MCH 00_149; • ♂; Great Smoky Mountains NP, N side Gabes Creek at Gabes Mountain trail; 35.7523°N, - 83.2419°W; 1 Aug. 1995; F. Coyle, Williams, Carbiener leg. ; • 2♀; Great Smoky Mountains NP, near Cosby campground, below group camp parking area; 35.7533°N, - 83.2066°W; 27 Aug. 2005; M. Hedin, R. Keith, J. Starrett, S. Thomas leg. ; MCH 05_097; • ♀; Great Smoky Mountains NP, S side Indian Camp Creek on Maddron Bald Trail ; 35.7378°N, - 83.2777°W; 16 Apr. 1994; M. Hedin, B. Dellinger leg. ; • 3♂, 4♀; Great Smoky Mountains NP, trail from Cosby to Low Gap ; 35.7453°N, - 83.197°W; 1 Aug. 2000; M. Hedin leg. ; MCH 00_145; • 2♀; Great Smoky Mountains NP, trail from Low Gap to Mt. Cammerer ; 35.754°N, - 83.1658°W; 1 Aug. 2000; M. Hedin leg. ; MCH 00_146.

Diagnosis.

As discussed above, this species is morphologically most similar to geographically adjacent Nesticus silvanus . Males have a fan-shaped paradistal paracymbial process (Fig. 16A-F ) that lacks the elongate retrolateral extension and well-sclerotized ventral edge found in N. silvanus . Epigyna are very similar to that of N. silvanus , but when viewed dorsally possess adjacent medial plate margins that are parallel to each other, unlike the indistinct or pointed margins in N. silvanus (but see Fig. 15E . vs. Fig. 17B ).

Description of ♂ holotype

(MCH specimen #1177). Carapace cream colored, gray pigmentation behind ocular area leading to midline and around edges. Legs pale yellow / cream. Abdomen with paired gray blotches on a light gray background. All eyes approximately equal in size, except for AMEs, ~ 1/2 width of ALEs. Eyes ringed with dark pigment. CL 1.45, CW 1.27, abdomen length 1.77, total body length 3.22. Leg I total length 10.55 (2.96, 0.54, 3.18, 2.8, 1.07), leg formula 1423, leg I / CW ratio 8.3. Paracymbium with a triangular ventral process with a sclerotized retrolateral edge, a dorsal process with an expanded serrate, distal portion, a heavily sclerotized triangular paradistal process, and a transparent, elongated, prolaterally directed dorsal process with a small triangular basal extension. Median apophysis a narrow oval with anteriorly directed edge coming to a point. Tegular process thick and sharp-tipped distally. Nose-like bulge at the base of the tegular apophysis. Distal tip of conductor bent and directed prolaterally.

♂ Variation.

Males from different sample locations vary in the presence / absence of a small basal projection of the dorsal process (Fig. 16B, C ).

Description of ♀ paratype

(MCH specimen #1181). Carapace cream colored, gray pigmentation behind ocular area leading to midline and around edges. Legs pale yellow / cream. Abdomen with paired dark gray blotches on a pale cream background. Eyes approximately equal in size, except for AMEs, ~ 1/2 width of ALEs. Eyes with rings of dark pigment. CL 1.51, CW 1.28, abdomen length 2.08, total body length 3.59. Leg I total length 9.27 (2.71, 0.58, 2.68, 2.23, 1.07), leg formula 1423, leg I / CW ratio 7.2. Epigynum possesses oval-shaped lateral lobes that extend to the posterior end of the median septum. Spermathecae visible beneath posterior lateral lobes, short and angled slightly upwards from perpendicular to septum. Viewed dorsally, large internal lobes extend anteriorly and possess sclerotized rims. Medial margins parallel to each other and touching along the midline.

♀ Variation.

Females from different sample locations vary in the symmetry of the interior epigynal plates (Fig. 17C, G ).

Distribution and natural history.

Found in rocky microhabitats from the rugged mountains of the eastern Great Smoky Mountains National Park, and adjacent eastern and southern locations (Fig. 13 ). The apparent gap at high elevations in this region (Fig. 13 ) likely reflects a lack of sampling in these less accessible high-elevation locations. Most collections include a modest number of specimens, suggesting a natural rarity for this taxon.

Along the Maddron Bald (along Indian Camp Creek) and the Low Gap to Mt. Cammerer trails (MCH 00_146) both Nesticus cherokeensis and N. binfordae sp. nov. were collected, indicating that these species are syntopic or nearly so at these locations. At both locations multiple collections were taken along an elevational transect and unfortunately lumped into a single collecting event. It is therefore not possible to discern if different species were collected at the exact same location (truly syntopic) or were closely parapatric along these elevational transects.

Etymology.

The species epithet ( Nesticus cherokeensis ) honors the larger Cherokee Nation whose ancestral homelands included the mountains of western North Carolina. Nesticus cherokeensis can also be found near The Qualla Boundary, home of the Eastern Band of Cherokee.

Remarks.

This species is strongly supported as sister to remaining members of the Nesticus tennesseensis group based on UCE evidence (Figs 3 , 4 ). Mitochondrial structuring is very pronounced, with each sample location (or set of adjacent locations) genetically distinct (Fig. 6 ).

Figures

Figure 3. UCE concatenated maximum likelihood tree. Distant outgroups removed (for graphical purposes), specimen numbers correspond to those in Suppl. material 3 (with detailed location provided in Suppl. material 1). Node numbers correspond to bootstrap (bold text) / gCF / sCF. Only bootstrap values below 100 shown, all others 100. gCF and sCF values rounded to nearest integer; sCF values below 38 highlighted with red text.

Figure 4. UCE ASTRAL species tree. Distant outgroups removed (for graphical purposes), specimen numbers correspond to those in Suppl. material 3 (with detailed location provided in Suppl. material 1). Included are quartet support values (rounded to nearest integer), and local posterior probability values (if less than 1.0, red text). Branch lengths in coalescent units for internal branches only, terminal branch lengths arbitrary. Internal branch to Nesticus cressleri truncated for graphical purposes.

Figure 6. COI IQT gene tree. Distant outgroups trimmed. Specimen numbers correspond to those in Suppl. material 3 (with detailed location provided in Suppl. material 1). Sequences from UCE capture denoted with " NODE ". Populations with a " Nesticus cooperi - like " male paracymbium denoted by small circles. Not all tip bootstrap values shown (see Suppl. material 4 for. tre file with all bootstrap values).

Figure 13. Distribution of Nesticus tennesseensis group species. Type localities designated with yellow circles. State boundaries and major cities shown for geographic context. Dashed lines circumscribe known species distributions.

Figure 15. Nesticus silvanus epigynal variation A North Carolina, Jackson Co., vicinity of Water Rock Knob, MCH specimen # 1083, ventral. North Carolina, Macon Co., Falls branch of Elijay Creek, MCH specimen # 1115, ventral (B), dorsal (C) North Carolina, Madison Co., W of Rocky Bluff campground, MCH 01 _ 139, ventral (D), dorsal (E). Scale bar: 0.5 mm.

Figure 16. Nesticus cherokeensis sp. nov. ♂ palps. North Carolina, Swain Co., Blue Ridge Parkway, below Ballhoot Scar overlook, MCH specimen # 1177, ventral (A), dorsal (B) C North Carolina, Haywood Co., S of Waterville, MCH 01 _ 134, dorsal D North Carolina, Jackson Co., Blue Ridge Parkway, near Bunches Bald Tunnel, MCH specimen # 1089, dorsal E North Carolina, Haywood Co., FR 288 above Pigeon River, MCH 01 _ 136, ventral F North Carolina, Swain Co., road to Balsam Mountain, MCH 02 _ 185, ventral. Scale bar: 0.5 mm.

Figure 17. Nesticus cherokeensis sp. nov. epigynal variation. North Carolina, Swain Co., Blue Ridge Parkway, below Ballhoot Scar overlook, MCH specimen # 1181, ventral (A), dorsal (B) North Carolina, Haywood Co., S of Waterville, MCH 01 _ 134, ventral (C), dorsal (D) Tennessee, Cocke Co., S side of Indian Camp Creek, MCH specimen # 1982, ventral (E), dorsal (F) North Carolina, Haywood Co., Cataloochee area, Sag Branch, ventral (G), dorsal (H). Scale bar: 0.5 mm.