Nesticus barri 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 barri Gertsch, 1984

Fig. 48A, C

Nesticus barri Gertsch, 1984: 36, figs 121-123, 161-163; Hedin and Dellinger 2005: 3, figs 2-10; Snowman et al. 2010: fig. 1; Carver et al. 2016: fig. 2.

Nesticus valentinei Gertsch, 1984: 29, figs 150-152.

Material examined.

Non type material: USA - Alabama, Jackson Co. • ♀; Fern Cave, AJK597; 1 Dec. 2018; M.L. Niemiller, M.E. Slay, T. Inebnit, J. Pinkley, J. Lamb, P. Pattavina, K. Sapkota, B. Miller, N. Mann leg.; MLN 18-051.8; • ♀, 1 imm; Fern Cave , AJK597, bottom of cave; 1 Aug. 2008; J. Pinkley leg.; JP 08-AJK597.1; • ♀; Fern Cave , AJK597, Johnston entrance; 2 Jun. 2018; M.L. Niemiller, M.E. Slay, T. Inebnit, B. Miller, et al. leg.; MLN 18-020.8; • ♀; Fern Cave , AJK597, Morgue - past first Bat Room; 23 Jun. 2018; A. Hinkle, S. Pitts leg.; AH 18-001.2; • ♀; Fern Cave , AJK597, upper formation passage; 2 Jun. 2018; M.L. Niemiller, M.E. Slay, T. Inebnit, B. Miller, et al. leg.; MLN 18-020.26; • ♀; Fern Cave , AJK597, upper north passage; 3 Jun. 2018; M.L. Niemiller, M.E. Slay, T. Inebnit, B. Miller, et al. leg.; MLN 18-021.1; • 8♀; Guess Creek Cave, E Trenton; 25 Sep. 1992; M. Hedin, J. Hedin, S O’Kane leg.; • 2♀, 1 imm; Moody Cave , AJK1189; 18 Mar. 2019; M.L. Niemiller, J. Lamb, A. Hinkle leg.; MLN 19-014.20; • ♀, 1 imm; Tumbling Rock Cave , AJK171; 8 Mar. 2014; M.L. Niemiller, C.D.R. Stephen, K.S. Zigler, R. Miller, C. Borer, C. Maddux, J. Clark, V. Leray leg.; MLN 14-011.10; - Alabama, Marshall Co. • 9♀; Bishop Cave , N of Guntersville Dam; 25 Sep. 1992; M. Hedin, J. Hedin, S O’Kane leg.; • ♂, 2♀; Bishop Cave ; 17 Aug. 2005; M. Hedin, R. Keith, J. Starrett, S. Thomas leg.; MCH 05_056; - Tennessee, Franklin Co. • ♂, 8♀; Keith Cave , S of Cowan; 24 Mar. 1995; M. Hedin, J. Hedin leg.; • 2♀, 2 imm; Little Crow Creek Cave , TFR15; 20 Sep. 2008; M.L. Niemiller, BT Miller, J Miller, N. Mann leg.; MLN 08-041; • ♂, 3♀; Lost Cove Cave , N / NE of Sherwood; 23 Sep. 1992; M. Hedin, J. Hedin, S O’Kane leg.; • 2♂, 7♀; Salt River Cave , W of Gonce, Alabama; 24 Mar. 1995; M. Hedin, J. Hedin leg.; • 2♀, 1 imm; Sinking Cove Cave , TFR25; 15 Oct. 2016; N.S. Gladstone leg.; NSG 16-TFR25.10; - Tennessee, Marion Co. • ♂, 2♀; Tate Spring Cave , SE of Monteagle; 15 Aug. 2004; M. Hedin, L. Hedin, R. Keith, J. Starrett, S. Thomas leg.; MCH 04_050 .

Diagnosis.

The diagnosis of Gertsch (1984) is here modified to reflect a close phylogenetic relationship to Nesticus furtivus . These taxa share an overall similarity in features of the male paracymbium and shape of the median apophysis but differ in the shape of the tegular apophysis (Fig. 48A-D ). In N. barri the tegulum is forked, with a basal projection shaped like a curved blade, and with a distal crescent-shaped tegular process lying close behind the quadrate median apophysis. The epigynum of N. barri is similar to that of distant relative N. lowderi in general structure (Fig. 47A-H ), but with internal plates (viewed dorsally) not as long. Females are distinctly different from N. furtivus , as discussed below in the diagnosis for this latter species.

Variation.

The shape of the basal tegular fork varies notably across cave locations. One male from Salt River Cave (MCH #2105) completely lacked a dorsal paracymbial process, without evidence that this was broken off. Variation in Nesticus barri epigynal morphology was illustrated in Hedin and Dellinger (2005), figs 2-8.

Distribution and natural history.

Known from possibly hundreds of caves in northwest Alabama and south-central Tennessee (Fig. 49 ; Hedin and Dellinger 2005: fig. 1; Snowman et al. 2010: fig. 1; Carver et al. 2016: fig. 2). Carver et al. (2016) reported on the reproductive biology of this species.

Remarks.

Based on consideration of morphology Hedin and Dellinger (2005) hypothesized that troglomorphic spiders from Tate Spring Cave, Tennessee represented a northern population of Nesticus barri . The mitochondrial data included here further support this hypothesis (Fig. 6 ).

Figures

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 47. Nesticus lowderi sp. nov. epigynal variation. North Carolina, Clay Co., Chunky Gal Mountain, Chestnut Branch of Barnard's Creek, MCH 99 _ 016 (SDSU _ TAC 000668) ventral (A), dorsal (B). North Carolina, Clay Co., Big Tuni Creek, MCH 02 _ 171, ventral (C), dorsal (D). Swain Co., Blowing Springs Cave, ventral (E), dorsal (F). North Carolina, Clay Co., Fires Creek Road, Picnic Area along Fires Creek, MCH 07 _ 108, ventral (G). North Carolina, Clay Co., Dave Barrett Fork of Eagle Fork Creek, MCH 02 _ 143, ventral (H). Scale bar: 0.5 mm. Septal bars outlined in image G to better reflect actual specimen.

Figure 48. Nesticus barri and N. furtivus genitalia. N. barri - Tennessee, Marion Co., Tate Spring Cave, MCH 04 _ 050, ♂ palp ventral (A), epigynum ventral (C). N. furtivus - Tennessee, Hamilton Co., Raccoon Mountain Caverns, SE Chattanooga, MCH 00 _ 137, ♂ palp ventral (B), epigynum ventral (# 1660) (D).

Figure 49. Distribution of Nesticus barri and Nesticus carteri groups. Type localities designated with yellow circles. State boundaries and major cities shown for geographic context. Dashed lines circumscribe known species distributions.