Revision of the Ephippiochthonius complex in the Iberian Peninsula, Balearic Islands and Macaronesia, with proposed changes to the status of the Chthonius subgenera (Pseudoscorpiones, Chthoniidae)
Author
Zaragoza, Juan A.
text
Zootaxa
2017
4246
1
1
221
journal article
36212
10.5281/zenodo.437611
3ff74501-6241-43b2-a52f-0e7580bb2f45
1175-5326
437611
D8594E96-D561-4A37-9073-B138EC7E95A7
Occidenchthonius dubius
(
Mahnert, 1993
)
,
n. comb.
(
Fig. 231
)
Chthonius
(
Ephippiochthonius
)
dubius
Mahnert 1993
: 976
–979, figs 13–16, table 1.
Not
Chthonius
(
Ephippiochthonius
)
dubius
:
Mahnert 2011a
: 41
–42 (misidentification, see
O. beieri
).
Type
locality.
Spain
,
Canary Islands
,
Santa Cruz de Tenerife province
,
Tenerife Island
, Icod de los Vinos,
Cueva de San Marcos
(
28°22′48″N
,
16°43′31″W
;
8 m
a.s.l.
)
.
Distribution.
Spain
:
Canary Islands
.
Diagnosis (
♀
).
A small, microphthalmic hypogean
Occidenchthonius
species. Movable cheliceral finger with isolated subapical tooth (
di
) and with prominent spinneret in female, unknown for male, lyrifissure
ldb
absent; anterior pair of eyes with low lens, posterior eyes absent, anterior margin of carapace without preocular microsetae, posterior margin with 2 macrosetae; chelal hand distinctly depressed at level of
ib
/
isb
, with a hump distad of
ib
/
isb
and moderate slope between trichobothria
ib
/
isb
and
eb
; chaetotaxy 4:5:4; fixed chelal finger with 17 teeth; distal half of movable chelal finger with 10 pointed teeth with dental canals, basal half of movable chelal finger with 12 rounded, partially fused, vestigial teeth, without canals, on raised lamina; pedipalpal femur (
♀
) 5.1 times longer than broad, length
0.49 mm
; chela (
♀
) 4.6 times longer than deep, length
0.70 mm
; ratio movable chelal finger/ chelal hand (
♀
) 1.4; lacking lyrifissures
ma1
and
ma2
, all other patterns present with their standard complements.
Type
material examined.
♀
holotype
(
MHNG
),
Spain
,
Canary Islands
,
Santa Cruz de Tenerife province
,
Tenerife Island
,
Icod
de los
Vinos
,
Cueva de San Marcos
(
28°22′48″N
,
16°43′31″W
;
8 m
a.s.l.
),
10.IX.1992
, leg.
P. Strinati
.
Description (
♀
;
♂
unknown).
Small, microphthalmic, hypogean species. Integument weakly depigmented; weak hispid granulation on posterolateral surfaces of carapace, on cheliceral hand and on bases of chelal fingers.
Carapace slightly longer than broad and weakly constricted posteriorly; medial part of anterior margin distinctly prominent, without a well-defined epistome, and strongly dentate; anterior eyes small with low convex lens and reflecting tapetum, their diameter equal to their distance from the anterior margin of carapace, posterior eyes absent. Chaetotaxy: 18 setae, without preocular microsetae, 2 setae in posterior row, formula 4:6:4:2:2, anteromedial setae
0.07 mm
long, sublateral ocular setae
0.06 mm
.
Cheliceral hand with 6–7 setae and 1–2 lateral microsetae, seta
vb
short (length
0.030 mm
), microsetae
0.027 mm
; hand with 4 dorsal and 1 ventral lyrifissure, lyrifissure
ldb
absent. Fixed finger with 7 teeth decreasing in size proximally, two distal teeth distinctly larger than others, 2 proximal microtubercles. Movable finger with an isolated subapical tooth (
di
), with 7 teeth decreasing in size proximally, the distal tooth larger than others; spinneret prominent and apically rounded in female, unknown for male; seta
gl
0.51 from base of movable finger. Rallum with 11 blades.
Chaetotaxy of tergites 4:4:4:4:6:6:6:6:1T2T1:4:1T2T1:0, tergites IX and XI each with 2 sublateral tactile setae. Chaetotaxy of sternites 9:(3)8(3):(2)6(2):8:6:6:6:6:2T1T2:0:2, lateral setae on sternite III macrosetal in size, sternite X with 2 submedial tactile setae.
Pedipalpal coxa with 5 setae (including 2 on manducatory process), distal marginal seta of disk
0.07 mm
long; coxa
I 3
+ 3 marginal microsetae, distal marginal seta
0.05 mm
long;
II 4
+ 13–14 bipinnate coxal spines,
III 5
+ 6– 7 bipinnate coxal spines and
IV 6
; intercoxal tubercle bisetose.
Pedipalp with femoral chaetotaxy 3:6:3:5:1. Chela (
Fig. 231
) with hand distinctly depressed at level of
ib
/
isb
, with a hump distad of
ib
/
isb
and moderate slope between trichobothria
ib
/
isb
and
eb
; marked hollow before base of movable finger with thicker cuticle; width shorter than depth; chaetotaxy 4:5:4, setae
ph3
and
ih5
present; distal end of hand and bases of chelal fingers with sclerotized condylar complex. Fixed finger with 17 mostly pointed teeth and with dental canals, 5 most proximal teeth progressively decreasing in size, first two distal teeth small, third tooth of normal row (
mt
) of fixed finger distinctly modified in shape and deviated in orientation with respect to the others, dental row reaching up to halfway between trichobothria
sb
and
b
, 7 proximal microtubercles; tip of finger with an accessory tooth (
td
) on antiaxial face; one pair of long antiaxial sensory setae (
as
) at the base, on either side of lyrifissure
fb
,
0.038 mm
long, distance between them
0.025 mm
, fixed finger depth at the base
0.045 mm
; 6 teeth at level of
est
/
it
occupying
0.1 mm
, distance between successive apices
0.019–0.021 mm
. Distal half of movable finger with 10 mostly pointed teeth with dental canals that reach up to slightly distad of halfway between trichobothria
st
and
sb
, the most proximad tooth slightly reduced in size and apically rounded, two distal ones tiny; basal half of movable chelal finger with 12 rounded, partially fused, vestigial teeth, without canals, on weakly raised lamina; dental row reaching up to halfway between trichobothria
sb
and
b
; basal apodeme long and apically indented; coupled sensilla
pc
between
sb
and
b
, slightly closer to
sb
. Trichobothria as in
Fig. 231
; trichobothrium
ist
distinctly distad of
esb
and very slightly proximad of lyrifissure
fb
; distance between
ib
/
isb
and
esb
approximately equal to that between
ib
/
isb
and the base of the hand; distance between
st
and
sb
1.8 times longer than that between
sb
and
b
; lacking lyrifissures
ma1
and
ma2
, all other chelal lyrifissure patterns present with their standard complements.
Measurements and ratios
. Female
holotype
: Body 1.52. Carapace 0.44/0.41 (1.1). Chelicera 0.34/0.17 (2.1), movable finger 0.18. Pedipalp: femur 0.49/0.10 (5.1), patella 0.21/0.11 (2.0), chela 0.70/0.15 (4.6), hand 0.29 (1.9), movable finger 0.40; ratio movable finger/hand 1.4, femur/movable finger 1.2, femur/carapace 1.1, chela/carapace 1.6, chela/femur 1.4.
Remarks.
Occidenchthonius dubius
is endemic to Tenerife
Island
. It is the only representative of
Occidenchthonius
from the
Canary Islands
that does not belong to the
machadoi
-group, due to the presence of the chelal hand seta
ih5
, the absence of cheliceral lyrifissure
ldb
, and the absence of preocular microsetae. Nor can it be assigned to the
verai
-group. Records of
O. dubius
from Gran Canaria given by
Mahnert (2011a)
are misidentifications of
O. beieri
n. sp.
(see remarks under that species). Comparisons with other species are made in the key and in the remarks under
O. anae
n. sp.
The above description incorporates in part that of
Mahnert (1993)
.