Nesticus sheari Gertsch, 1984

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 sheari Gertsch, 1984

Fig. 54A-F

Nesticus sheari Gertsch, 1984: 32, figs 79-81, 135-137.

Material examined.

Type material: Holotype: USA - North Carolina, Graham Co. • ♂ holotype; Joyce Kilmer Memorial Forest, Poplar Cove ; 30 May 1975; W.A. Shear leg.; AMNH; New collections from type locality: - North Carolina, Graham Co. • 3♂, 7♀; Joyce Kilmer Memorial Forest , NW of Robbinsville; 35.3585°N, - 83.9291°W; 1 Aug. 1992; M. Hedin leg.; • 4♀; Joyce Kilmer Memorial Forest , NW of Robbinsville; 35.3585°N, - 83.9291°W; 28 Aug. 2002; M. Hedin, M. Lowder, P. Paquin leg.; MCH 02_164; • 2♀; Joyce Kilmer Memorial Forest , NW of Robbinsville; 35.3585°N, - 83.9291°W; 17 Aug. 2007; M. Hedin, M. McCormack, S. Derkarabetian leg.; MCH 07_115; Non type material. - Georgia, Fannin Co. • 19♀; Cohutta Wilderness, Cowpen Trail, NW Three Forks Mountain trailhead; 34.8905°N, - 84.5715°W; 22 Aug. 2002; M. Hedin, M. Lowder, P. Paquin leg.; MCH 02_151; Georgia, Union Co. • 4♀; Sosebee Cove State Natural Area , off Hwy 180, 2 mi W jnct Hwy 19, S Blairsville; 34.7617°N, - 83.9482°W; 18 Apr. 1994; M. Hedin leg.; - North Carolina, Cherokee Co. • 4♀; along Tipton Creek , 1.2 mi. SNC/TN stateline; 35.2503°N, - 84.0724°W; 26 Aug. 2002; M. Hedin, M. Lowder, P. Paquin leg.; MCH 02_158; • 2♀; FR 50 Shuler Creek , below Wolf Ridge; 35.2424°N, - 84.2227°W; 17 Aug. 2004; M. Hedin, R. Keith, J. Starrett, S. Thomas leg.; MCH 04_054; - North Carolina, Graham Co. • ♂, 2♀; along Wright Creek , S Santeetlah Creek , W of Seven Springs Gap; 35.3258°N, - 83.9647°W; 19 Aug. 1991; B. Dellinger, D. Loch leg.; - Tennessee, Loudon Co. • ♂, ♀; Blankenship Cave , TLN1; 25 Jan. 2014; M.L. Niemiller, E.T. Carter leg.; MLN 14-006; - Tennessee, Monroe Co. • ♂, 2♀, 2 imm; Alans Hideaway Cave , TMO9; 16 Nov. 2013; M.L. Niemiller, E.T. Carter, M. Finkle leg.; MLN 13-079.1; • 2♀; along North River , FR 217, Unicoi Mountains ; 35.3215°N, - 84.1199°W; 17 Aug. 2007; M. Hedin, M. McCormack, S. Derkarabetian leg.; MCH 07_112; • ♂, 16♀, 4 imm; along Tellico River , near Bald River Falls ; 35.3248°N, - 84.1787°W; 26 Aug. 2002; M. Hedin, M. Lowder, P. Paquin leg.; MCH 02_157; • 7♀; Bald River , FR 126, E of Holly Flats campground; 35.2855°N, - 84.1586°W; 17 Aug. 2007; M. Hedin, M. McCormack, S. Derkarabetian leg.; MCH 07_113; • 2♂, 8♀; Citico Creek near confluence with Flat Creek ; 35.4252°N, - 84.1047°W; 27 Aug. 2002; M. Hedin, M. Lowder, P. Paquin leg.; MCH 02_160; • ♀; Doublecamp Creek , 0.5 mi. E confluence with Citico Creek , Unicoi Mountains ; 35.4224°N, - 84.0847°W; 17 Aug. 2007; M. Hedin, M. McCormack, S. Derkarabetian leg.; MCH 07_114; • ♀, 4 imm; Gay Cave , TMO3; 16 Nov. 2013; ML Niemiller, C.D.R. Stephen, M. Finkle leg.; MLN 13-077; • 3♀, 5 imm; Lick Creek Cave , TMO8; 16 nov. 2013; M.L. Niemiller, C.D.R. Stephen, E.T. Carter, M. Finkle leg.; MLN 13-078; - Tennessee, Polk Co. • ♂, 10♀; FR 221, N of Peavine Mountain, vicinity Big Frog Mountain Wilderness ; 35.0531°N, - 84.5139°W; 23 Aug. 2002; M. Hedin, M. Lowder, P. Paquin leg.; MCH 02_152; • ♂; S Ocoee River at Thunder Rock Road, off Hwy 64; 35.0743°N, - 84.4852°W; 17 Aug. 2004; M. Hedin, R. Keith, J. Starrett, S. Thomas leg.; MCH 04_052.

Diagnosis.

The diagnosis of Gertsch (1984) is here modified to recognize relationships to other Nesticus reclusus group members. Male paracymbium with the combination of translucent blade-like paradistal process, distal process with twisted, tubular tip; well-sclerotized, toothlike dorsomedial process adjacent to small flange-like ventromedial process (Fig. 54A, B ). These paracymbium characters are similar to those found in N. bishopi and N. stupkai . Male tegular apophysis with a general S-curve, distal process a truncate curving blade, basal process nipple-like. Acute distal median apophysis. In females the posterior end of the epigynal median septum is “squared-off” on three sides, like a chisel (Fig. 54C-F ), projecting inwards towards the abdomen.

Variation.

In males from non-type locations the ventromedial process is more confluent with the ventral process (less displaced medially) and more elongate.

Different populations exhibit very little epigynal variation despite a large and fragmented geographic distribution. Some adult females from Holly Flats campground are approximately one-half the size of other adult females.

Distribution and natural history.

Previously known only from the type locality at Joyce Kilmer Memorial Forest, which now represents one of the easternmost known records for the species. The species distribution almost forms a circle in the montane uplands that surround the Ducktown lowlands (lacking the eastern edge), with disjunct Cohutta, Sosebee Cove, and Blankenship Cave populations (Fig. 53 ). It appears to surround the geographic distribution of the more narrowly distributed Nesticus bondi . Previously thought to be a strictly montane taxon, but we report here several important new cave records.

As an example of natural history we include here field notes for Cohutta Wilderness (MCH 02_151) where we collected 19♀. Notes read "small drainage in pine forest, rocks in drainage, moist but not running water", where spiders were collected from beneath rocks.

As discussed above Nesticus sheari (4♀) was found in sympatry with N. bondi (♂, 6♀) at Tipton Creek. Because we did not identify specimens directly in the field, it remains unclear if these different species were found side-by-side or were perhaps somehow segregated by microhabitat. Nesticus sheari was also collected in sympatry with the nesticid Eidmanella Roewer, 1935 at Doublecamp Creek (07_114); Nesticus is otherwise rarely found in sympatry with members of this genus.

Remarks.

Monophyletic on mitochondrial and nuclear trees, with high gene and site CF values for the latter. Phylogenomic evidence strongly supports Nesticus sheari as sister to remaining members of the Nesticus reclusus group (Figs 3 , 4 ).

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 53. A distribution of Nesticus reclusus group species B distribution of Nesticus jonesi. Type localities designated with yellow circles. State boundaries and major cities shown for geographic context. Dashed lines circumscribe known species distributions. The geographic distribution of " N. cooperi - like " populations is circled; this includes some female-only locations which are inside this distribution and included here only for purposes of graphical convenience.

Figure 54. Nesticus sheari genitalia. Tennessee, Polk Co., N of Peavine Mountain, vicinity Big Frog Mountain Wilderness, MCH 02 _ 152, ♂ palp, dorsal (A), ventral (B). Tennessee, Polk Co., vicinity Big Frog Mountain Wilderness, MCH 02 _ 152, epigynum, ventral (C), dorsal (D). Georgia, Union Co., Sosebee Cove State Natural Area, MCH specimen # 1995 epigynum, ventral (E), dorsal (F). Scale bar: 0.5 mm.