Survey of the Ethiopian linyphiid spider fauna. I. Subfamily Erigoninae (Arachnida, Araneae, Linyphiidae)
Author
Tanasevitch, Andrei V.
text
Zootaxa
2023
2023-09-20
5346
4
420
442
http://dx.doi.org/10.11646/zootaxa.5346.4.4
journal article
269786
10.11646/zootaxa.5346.4.4
f631dec3-14e8-4dab-b340-df57d7cc8c5a
1175-5326
8390441
3D23DF3F-6B66-4C60-BE3D-A98EA43F01C5
Savignia ericola
new species
Figs 11
,
12
Type material.
Holotype
:
J (
ZMMU
):
ETHIOPIA
,
Oromia Region
,
Asela Zone
, ca 30 air-km SE from
Asela
(= Assela),
Arsi Mountains
N.P.
, road from
Digelu
to
Ticho
,
3500–3505 m
a.s.l.
,
7.81944°N
39.35429°E
,
Erica arborea
bushes, with grass and green mosses, sifting mosses,
30.X.2022
, leg.
A. Tanasevitch
[Eth018].
Etymology.
The specific epithet is a Latin adjective meaning a heather-dweller (
Erica arborea
).
Diagnosis.
Based on the formula of chaetotaxy (2.2.1.1) and trichobothriotaxy (Tm I–III present, TmIV absent), the modified carapace, as well as the hypertrophied distal suprategular apophysis, the new species is evidently a member of the
Savignia
-genus group
sensu
Millidge (1977)
. Among the genera of this group, the new species seems most appropriate to be provisionally assigned to
Savignia
Simon, 1884
, as certain resemble is observed in the structure of the embolic division, namely, the peculiar shape of the embolus, as well as by the presence of a narrow process at its base (MRP in
Fig. 12E
). The shape of the embolus is similar to that in many Asian congeners, e.g.
S. amurensis
Eskov, 1991
,
S. eskovi
Marusik, Koponen & Danilov, 2001
,
S. saitoi
Eskov, 1988
,
S. zero
Eskov, 1988
, etc., all of which also show a median radical process in the embolic division. However, the new species stands apart among other congeners in lacking of a mesal outgrowth on the distal suprategular apophysis (MOSA in
Tanasevitch & Trilikauskas 2006
, figs 2, 4), a significant generic synapomorphy. Besides this,
Savignia ericola
n. sp.
possesses a characteristic “
Bisetifer
-like” palpal tibia which bears three long, strong, lateral setae absent from other congeners of
Savignia
-genus group. This new species is only conditionally to be placed in
Savignia
, so at least until a female is found. If the structure of the epigynum turns out to be similar to that of
Savignia
(namely, with a bisected ventral plate), then the placement of the new species into the genus will become justified. At the same time, it is possible that the new species represents a new genus of the
Savignia
-genus group.
FIGURE 11.
Photographs of male holotype (
A–D
) of
Savignia ericola
n. sp.
A
, habitus, dorsal view;
B
,
C
, same, lateral and anterolateral view, respectively;
D
, same, frontal view. Scale bar: 0.5mm.
Description.
Male
holotype
. Total length 1.83. Carapace slightly modified as shown in
Figs 11A–C
, 1.03 long, 0.63 wide, pale greyish brown to greyish yellow. Anterior part of carapace somewhat protruded anteriorly, eyes relatively small. Chelicerae 0.22 long, a mastidion absent. Legs yellow. Leg I 2.06 long (0.63 + 0.22 + 0.48 + 0.40 + 0.33), IV 2.19 long (0.63 + 0.20 +0.58 + 0.48 + 0.30). Chaetotaxy 2.2.1.1, spines about as long as 0.5–1 diameter of corresponding leg segment. Metatarsi I–III with a trichobothrium each. TmI 0.41. Palp (
Figs 12A–G
): Patella slightly elongated. Tibia with a dorsal, conical, apically rounded outgrowth and a small projection bearing three long, stout and slightly curved setae. Paracymbium J-shaped. Distal suprategular apophysis very large, massive, ending with a strong, straight spike. Radix rounded proximally, with a membranous tissue near middle, a flat, subtrapeziform, anterior apophysis (ARA in
Fig. 12E
), and an relatively long, narrow, apically unciform process (
Figs 12E, F
) situated at base of embolus. Embolus starting from middle of radix as a narrow stripe, sharply curved in middle part to gradually taper thereafter into a thin and curved tip. Opisthosoma 0.90 long, 0.58 wide, pale grey (
Figs 11A–C
).
Female
unknown.
Distribution.
Known only from the
type
locality in the highlands of Arsi Mountains N.P. (
3500–3505 m
a.s.l.),
Oromia Region
,
Ethiopia
.