Cybaeus (Araneae: Cybaeidae): the consocius species group of the Californian clade
Author
Bennett, Robb
0000-0002-6587-7079
ennett@shaw.ca
Author
Copley, Claudia
0000-0002-8184-5819
ccopley @ royalbcmuseum. bc. ca; https: // orcid. org / 0000 - 0002 - 8184 - 5819
ccopley@royalbcmuseum.bc.ca
Author
Copley, Darren
0000-0002-1944-4272
dcopley @ royalbcmuseum. bc. ca; https: // orcid. org / 0000 - 0002 - 1944 - 4272
dcopley@royalbcmuseum.bc.ca
text
Zootaxa
2021
2021-04-29
4965
3
401
436
journal article
7001
10.11646/zootaxa.4965.3.1
6cadad22-abf2-4abe-9165-156d5c63ece3
1175-5326
4752531
94FB89CF-2083-4FAC-AE60-B8CCF1D5FE8E
Cybaeus consocius
Chamberlin and Ivie
Figs 2–9
,
16–17
,
20
,
84
Cybaeus consocius
Chamberlin and Ivie 1932: 25
, fig. 61.
Roewer 1954: 90
.
Bonnet 1956: 1301
.
Roth and Brown 1986: 3
.
Bennett 2006: 481
, figs 23–25.
Copley
et al.
2009: 372
, fig. 7.
World Spider Catalog 2021
.
Cybaeus marinensis
Chamberlin and Ivie 1932: 25
, fig. 60.
Roewer 1954: 91
.
Bonnet 1956: 1302
.
Cybaeus angelus
Chamberlin and Ivie 1942: 16
, fig. 50.
Roewer 1954: 9
.
Roth and Brown 1986: 3
.
Cybaeus mariensis
:
Roth and Brown 1986: 4
(incorrect subsequent spelling of
C. marinensis
).
Type material examined.
U.S.A.
:
California
:
Holotype
female
of
C. consocius
, Marin County
, no date,
R
.
V
.
Chamberlin
(
AMNH
), subsequently lost
.
Neotype
male
of
C. consocius
, designated by
Bennett (2006)
,
Marin County
, south end of
S.P. Taylor State Park
,
1.xi.1953
,
V
.
D. Roth
& G.
Marsh
(
AMNH
)
.
Holotype
female
of
C. angelus
.
Los Angeles County
,
Los Angeles
, no date, no collector (
AMNH
)
.
Holotype
female
of
C. marinensis
.
Marin County
, no date,
R
.
V
.
Chamberlin
(
AMNH
)
.
See discussion of
type
material and synonymy in
Bennett (2006)
.
Other material examined
.
U.S.A.
:
California
:
Marin.
1♀
, E slope
Mt Tamalpais
,
14.v.1952
,
H.S. Dybas
(
FMNH
);
2♂
3♀
,
Muir Woods
,
5.ix.1927
(
AMNH
);
1♀
,
Muir Woods
,
24.x.1953
,
V
.D.
Roth
(
CAS
);
1♀
,
Ring Mountain Preserve
,
S of Corte Madera
,
18.xii.1982
,
V
.F.
Lee
(
CAS
);
3♀
,
Ross Bald Hill
,
1.iii.1991
,
D. Ubick
&
T
.
Briggs
(
CAS
);
1♀
San Anselmo
,
San Rafael Ridge
,
19.ix.1995
,
L.G. Freihofer
(
CAS
);
Mendocino.
4♀
, near
Lake Mendocino
, P.
R
.
Craig
&
C. Kirsch
(
CAS
);
Napa.
3♀
,
2mi.
W Oakville
,
31.xii.1953
(
AMNH
);
1♀
,
3 mi
W
Oakville
,
15.ii.1954
,
V
.D.
Roth
&
R
.
O. Schuster
, (
AMNH
);
1♀
,
7 mi.
W Oakville
,
15.ii.1954
(
AMNH
);
2♀
,
7 mi.
W
Oakville
,
13.xii.1957
,
L.M. Smith
&
R
.O.
Schuster
(
CAS
);
3♀
,
Skyline Park
,
Camp Coombs
,
22.i.1999
,
T
.
Briggs, W
. Rauscher &
D. Ubick
(
CAS
);
San Francisco.
1♀
,
San Francisco
,
Marx
(
MCZ
);
Santa Clara.
2♀
,
Alum Rock Park
,
22.ii.2013
,
I.M. Sokolov
(
CAS
);
Solano.
1♀
,
Cordelia
,
14.9 mi
N of Benicia
,
9.ii.1964
, P.
R
.
Craig
& D.L.
Craig
(
CAS
)
.
Diagnosis
. The male of
C. consocius
is unlikely to be confused with the males of the other species in the
consocius
group and is diagnosed by the unique forked tip of the proximal arm of the tegular apophysis (
Figs 3–4
,
20
). In ventral view the two forks are at right angles to each other with the larger, ventral-most fork directed prolaterally and featuring a sharp-edged longitudinal ridge medially along the ventral surface while the smaller fork is directed proximally and resembles the keel of a sailboat. The female of
C. consocius
is only likely to be confused with the females of
C. hesper
or
C. hummeli
spec. nov.
; those three species have similar vulval morphology featuring, in dorsal view, a distinctive U-shaped proximal loop of each copulatory duct (
Figs 7
,
15
,
25
). In
C. consocius
and
C. hesper
the atrium is undivided and of an inverted U-shaped form (
Figs 5–14, 16–17
); in
C. hummeli
spec. nov.
the atrium is divided into a pair of longitudinal slits or depressions separated by a medial convex septum (
Figs 23–24, 26
). The females of
C. consocius
and
C. hesper
can be separated by differences in atrial and copulatory duct morphology. The medial area of the atrium between the lateral arms of the inverted “U” in
C. consocius
is smoothly concave (
Figs 5, 9
,
16
)
versus
laterally concave and medially convex (
Fig. 13
) in
C. hesper
. The copulatory ducts in
C. consocius
are attached to the lateral margins of the atrium and extend at best only slightly anterior of the anterior margin of the atrium (
Figs 6–8
,
17
); in
C. hesper
the copulatory ducts are attached to the anterolateral margins of the atrium and extend well anterior of the anterior margin of the atrium (
Figs 14–15
).
FIGURES 1–4.
Cybaeus
spp.
, males, left palpus (1
C. simplex
from Ashland watershed, Oregon; 2–4
C. consocius
from Muir Woods, California). 1 Patella, tibia, and genital bulb, ventral. 2 Patella and tibia, dorsal. 3–4 Genital bulb (3 ventral, 4 retrolateral). DA—distal arm of tegular apophysis, E—embolus, PA—proximal arm of tegular apophysis, PS—peg setae, PTA—patellar apophysis, RTA—retrolateral tibial apophysis.
FIGURES 5–9.
Cybaeus consocius
, females from California, copulatory organ (5–7 holotype, 8 from Mount Tamalpais, 9 from near Oakville). 5 Epigynum, ventral. 6–8 Vulva (6, 8 ventral, 7 dorsal). 9 Atria, ventral. BG—Bennett’s gland, CD—copulatory duct, HS—head of spermatheca, SS—stalk of spermatheca. Unlabelled arrows indicate anterior margin of atrium.
Description
. Ventral tibia I macrosetae: 2-1p-2-1p-0.
Male
: (n=3). Length of patellar apophysis about 3/4 width of patella, six small peg setae dorsally and around tip (
Fig. 2
). Measurements (n=3). CL 2.20, 2.25, 2.6; CW 1.58, 1.68, 1.85; SL 1.11, 1.13, 1.27; SW 1.05, 1.07, 1.21.
Neotype
is largest specimen.
Female
: (n=31). Copulatory ducts (
Figs 6–8
,
17
) somewhat membranous, contiguous or separate at atrium. Spermathecal stalks well separated (
Fig. 7
). Measurements (n=14). CL 1.60–2.43 (2.11±0.23), CW 1.09–1.57 (1.44±0.15), SL 0.88–1.17 (1.08±0.08), SW 0.81–1.10 (1.01±0.08).
Holotypes
:
C. consocius
CL
2.20, CW 1.53, SL 1.12, SW 1.04;
C. angelus
CL
2.30, CW 1.57, SL 1.13, SW 1.04;
C. marinensis
CL
2.43, CW 1.70, SL 1.17, SW 1.10.
Distribution and natural history.
Coastal
California
from southern Mendocino County to northern Santa Clara County (
Fig. 84
). Most records are from the San Francisco Bay area. Following
Bennett (2006)
, we believe the record from the Los Angeles area (a single specimen, the
holotype
of
C. angelus
) to be erroneous: no other species of the
consocius
group is known to range that far south and no further specimens of
C. consocius
have been recorded from the Los Angeles area subsequent to the original description of
C. angelus
. This record is not included on the distribution map. Also see distribution discussion under
C. hesper
. Mature males have been collected in September and November.