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
Author
Hedin, Marshal
Department of Biology, San Diego State University, San Diego, California 92182 - 4614, USA
mhedin@sdsu.edu
Author
Milne, Marc A.
https://orcid.org/0000-0002-1943-0161
Department of Biology, University of Indianapolis, Indianapolis, Indiana 46227, USA
text
ZooKeys
2023
2023-02-03
1145
1
130
http://dx.doi.org/10.3897/zookeys.1145.96724
journal article
http://dx.doi.org/10.3897/zookeys.1145.96724
1313-2970-1145-1
830628C276CD4641BFC6144CD775ED6B
ACBBD138B7375B0D9F63CE792A82F653
Nesticus lowderi
sp. nov.
Figs 46A-D
, 47A-H
Material examined.
Type material:
Holotype
:
USA
-
North Carolina
,
Clay Co.
•
♂
holotype
;
Chunky Gal Mountain
,
Chestnut Branch of
Barnard's
Creek
;
35.0857°N
, -
83.6327°W
;
6 May. 1999
;
M. Hedin
,
B. Dellinger
leg.; MCH 99_016 (SDSU_TAC000667)
;
Paratypes
: -
Clay Co.
•
3♀
; data as for holotype;
Non
type material
: -
Clay Co.
•
♂
; along
Barnard's
Creek
, N side of
Chunky Gal Mountain
;
35.0868°N
, -
83.6372°W
;
24 Apr. 1992
;
B. Dellinger
leg.
; •
♀
;
Eagle Fork Creek
(
Dave Barrett
)
SE of Shooting Creek
N of
Hightower Bald
;
35.0075°N
, -
83.6225°W
;
20 Aug. 2002
;
M. Hedin
,
F. Coyle
,
M. Lowder
,
P. Paquin
leg.
;
MCH 02_143; •
♂
,
6♀
;
Fires Creek
Road,
Picnic Area
along
Fires Creek
;
35.0955°N
, -
83.8586°W
;
16 Aug. 2007
;
M. Hedin
,
M. McCormack
,
S. Derkarabetian
leg.
;
MCH 07_108; •
3♂
,
5♀
;
Fires Creek
,
Long Branch
, just up from
Short Branch
;
35.1467°N
, -
83.7618°W
;
21 Aug. 2002
;
M. Hedin
,
F. Coyle
,
M. Lowder
,
P. Paquin
leg.
;
MCH 02_144; •
2♀
, 1 imm;
Fires Creek
, near
Leatherwood Falls
, just NE
Fires Creek Picnic Area
;
35.0961°N
, -
83.8566°W
;
18 Aug. 2004
;
M. Hedin
,
R. Keith
,
J. Starrett
,
S. Thomas
leg.
;
MCH 04_060; •
2♀
; FR 440, along
Big Tuni Creek
,
2 mi.
N Woods Road
;
35.1025°N
, -
83.7007°W
;
16 Aug. 2007
;
M. Hedin
,
M. McCormack
,
S. Derkarabetian
leg.
;
MCH 07_107; •
♂
,
7♀
, 7 imm; FR 440,
Big Tuni Creek
, E
Tusquitee Bald
near
Bob Allison Picnic Area
;
35.1463°N
, -
83.6974°W
;
30 Aug. 2002
;
M. Hedin
,
M. Lowder
,
P. Paquin
leg.
;
MCH 02_171; •
♂
; W side
Chunky Gal Mountain
,
Hwy
64, near scenic overlook;
35.0627°N
, -
83.6204°W
;
6 May. 1999
;
M. Hedin
,
B. Dellinger
leg.
;
MCH 99_019; -
Swain Co.
•
2♀
;
Nantahala River
Gorge,
Blowing Springs Cave
;
10 Sep. 2001
;
J.D. Mayes
leg.
Diagnosis.
Several male features distinguish
Nesticus lowderi
from other members of the species group (and Appalachian clade), including the distinctive shape of the posterior keel of the forked tegular apophysis and the low sinuous paradistal process (Fig.
46A-D
). Median bars, extending V-shaped upwards from the median septum and interrupting the epigynal pockets, diagnose
N. lowderi
females from other members of the species group and other common regional taxa (e.g.,
N. reclusus
).
Figure 46.
Nesticus lowderi
sp. nov. ♂ palps. North Carolina, Clay Co., Chunky Gal Mountain, Chestnut Branch of
Barnard's
Creek, MCH 99_016 (SDSU_TAC000667), dorsal (
A
), ventral (
B
)
C
North Carolina, Clay Co., Big Tuni Creek, MCH 02_171, ventral
D
North Carolina, Clay Co., Fires Creek Road, Picnic Area along Fires Creek, MCH 07_108, ventral. Scale bar: 0.5 mm.
Description of ♂ holotype
(SDSU_TAC000667).
Carapace cream-colored, faint gray pigmentation behind ocular area leading to midline. Legs pale yellow / cream. Abdomen with many dark gray blotches on a pale cream background. All eyes approximately equal in size, except for AMEs, ~ 1/2 width of ALEs. Eyes with rings of dark pigment. CL 1.32, CW 1.2, abdomen length 1.48, total body length 2.8. Leg I total length 9.88 (2.71, 0.58, 2.9, 2.59, 1.1), leg formula 1423, leg I / CW ratio 8.2. Ventral paracymbial process consists of a large, basal lobe that broadens down length of paracymbium. Distal process somewhat spoon-shaped, dorsal process a low lobe, and the paradistal process consists of a sinuous, prolaterally directed extension with a heavily sclerotized anterior edge. Median apophysis rectangular with an anteriorly directed point and a sclerotized prolateral edge. Tegulum forked, with strong posterior keel including a wide lobe with a flattened edge. Distal tegular process crescent-shaped with a heavily sclerotized point directed anterolaterally, closely appressed to median apophysis. Distal tip of conductor bent and directed prolaterally.
♂ Variation.
Males from different locations varied slightly in the shape of the basal fork of the tegular apophysis (Fig.
46A-D
).
Description of ♀ paratype
(SDSU_TAC000668).
Carapace dusky cream to orange, with faint gray pigmentation behind ocular area leading to midline and around edges. Leg pale yellow / cream. Abdomen with paired dark gray blotches on a light gray background. All eyes approximately equal in size, except for AMEs, ~ 1/2 width of ALEs. Eyes with rings of dark pigment. CL 1.25, CW 1.11, abdomen length 1.46, total body length 2.71. Leg I total length 8.34 (2.41, 0.51, 2.39, 2.04, 0.99), leg formula 1423, leg I / CW ratio 7.5. Epigynal pockets interrupted by median bars that extend upwards V-shaped from base of median septum to nearly the top of the larger pocket (giving an overall appearance of an anchor, Fig.
47A-H
). The presence of these bars forms septal grooves that lie directly adjacent to the median septum, and smaller pockets lateral to the V-shaped bars. Median septum slightly protruding posteriorly past lateral lobes. Spermathecae elongated and curved along lateral borders of epigynum, approximately banana-shaped. Ventrolateral sides of epigynal plate bulging (convex), as viewed from the side. Viewed dorsally, large internal lobes extend anteriorly and possess sclerotized rims. Interior margins directed inward diagonally towards the center of the epigynum.
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_TAC000668) 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.
♀ Variation.
Epigynal structure fairly uniform across collecting locations (Fig.
47A-H
). Blowing Springs Cave females are concolorous and relatively long-legged.
Distribution and natural history.
Most populations are from the Chunky Gal, Tusquitee, and Valley River Mountains of western North Carolina (Fig.
42
).
Holler et al. (2020)
attributed female specimens from Blowing Springs Cave to
Nesticus cooperi
(=
N. reclusus
); we instead have identified these as
N. lowderi
based on epigynal morphology, including the inward curve of the internal plates (Fig.
47A-H
). This would represent a disjunct northern-most record for
N. lowderi
(Fig.
42
) and should be confirmed with the collection of males and /or nuclear DNA data from this location. Another possibility is sympatry at this location.
At Fires Creek (MCH 02_144),
Nesticus lowderi
(3♂, 5♀) was found in syntopy with
N. reclusus
(♂, 4♀); field notes read "30-minute survey, 3 persons, S-facing and N-facing rock fields". Because we did not identify specimens directly in the field it remains unclear if these different species were truly syntopic or were segregated somehow at this location. Also, at least 15 immatures were collected at this location but were not identified to species because of sympatry.
Collection records suggest that this species is less common in the Chunky Gal Mountains than in the more westerly Tusquitee and Valley River Mountains.
Etymology.
This species is named to recognize and honor Michael Lowder, faculty member at Stanly Community College, native North Carolinian, fan of western North Carolina, and collector of many Appalachian
Nesticus
. Michael was the first graduate student of MH, who remains forever grateful for our continued friendship and reflects on our early lab and field time together with great fondness.
Remarks.
The extent of mitochondrial divergence observed in this taxon over a small geographic region (including only Chunky Gal, Tusquitee, and Valley River Mountains) is notable (Fig.
6
).