A taxonomic revision of the tube-web spiders of the genus Ariadna (Araneae: Segestriidae) in Tasmania
Author
Marsh, Jessica R.
0000-0002-4062-4155
Harry Butler Research Institute, Murdoch University, Murdoch, Western Australia 6150, Australia & Earth and Biological Sciences, South Australian Museum, GPO Box 234, Adelaide, South Australia 5001, Australia & jess. marsh @ murdoch. edu. au; https: // orcid. org / 0000 - 0002 - 4062 - 4155
jess.marsh@murdoch.edu.au
Author
Stevens, Mark I.
0000-0003-1505-1639
Earth and Biological Sciences, South Australian Museum, GPO Box 234, Adelaide, South Australia 5001, Australia & School of Biological Sciences, University of Adelaide, South Australia 5005, Australia. & mark. stevens @ samuseum. sa. gov. au, https: // orcid. org / 0000 - 0003 - 1505 - 1639
Author
Framenau, Volker W.
0000-0002-7724-3831
Harry Butler Research Institute, Murdoch University, Murdoch, Western Australia 6150, Australia & Department of Terrestrial Zoology, Western Australia Museum, Locked Bag 49, Welshpool DC, Western Australia 6986, Australia Zoological Museum Hamburg, Leibnitz Institute for the Analysis of Biodiversity Change (LIB), Centre for Taxonomy & Morphology, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany & volker. framenau @ murdoch. edu. au; https: // orcid. org / 0000 - 0002 - 7724 - 3831
volker.framenau@murdoch.edu.au
text
Zootaxa
2022
2022-03-03
5105
2
151
201
journal article
20383
10.11646/zootaxa.5105.2.1
412c4939-6e62-41c6-b2a9-e3d2053f9fcf
1175-5326
6332569
4F6F5BC6-2AAF-4B23-882E-F77C63BE4CC2
Ariadna fragilis
sp. nov.
Figs 20a–h
,
21a–c
,
19
http://zoobank.org/NomenclaturalActs/4fecfd82-2de9-4643-a792-a8938643c7d6
Type material.
Holotype
♂
.
AUSTRALIA
:
Tasmania
:
Mount Chappell Island in Bass Strait
,
40.27°S
,
147.52°E
,
29 July 1989
–
7 August 1989
, coll.
S. Fearn
(
QVMAG
QVM
:2020:13:0111)
Other material examined.
Known only from the
type
specimen.
Etymology.
The specific epithet is a Latin adjective meaning ‘fragile’ and refers to the slender form of the species.
Diagnosis.
Ariadna fragilis
sp. nov.
is most similar to
A. abbreviata
sp. nov.
,
A. clavata
and
A. tigrina
sp. nov.
. It is differentiated from
A. abbreviata
sp. nov.
by the lack of shortened, blunt macrosetae prolaterally on metatarsus I (
Fig. 20f–h
cf.
Fig. 1f–h
). It is differentiated from
A. clavata
by its slenderer pedipalp tibia compared to the cymbium length and by the embolus, which is less hooked apically in
A. fragilis
sp. nov.
, than in
A. clavata
(
Fig. 21a, b
cf. fig.
1g
, i
Marsh
et al.
2018
). The species is differentiated from
A. tigrina
sp. nov.
by its longer and slenderer pedipalp tibia (
Fig. 21a, b
cf.
Fig. 39a, b
), and by the pattern of macrosetae on the tibia and metatarsus of leg I, which is paired in
A. fragilis
sp. nov.
(
Fig. 20f–h
cf.
Fig. 37f–h
).
Description
.
♂
(based on
holotype
; QVMAG QVM:2020:13:0111). Total length 4.7.
Colour in ethanol:
Carapace golden, orange brown, sparse, scattered light setae, caput area raised anterior to fovea and lighter yellow brown; sternum yellow brown, with sparse long brown setae, maxillae yellow brown, paler in colour apically, labium darker orange brown, chelicerae orange brown; abdomen dorsally pale grey, with nine dark grey, clearly defined chevrons, with triangular extensions in the centre and joined by dark median line, ventrally cream with dark patches centrally and laterally. Legs yellow brown, with darkened patches distally tibiae I and II, with sparse brown setae (
Fig. 20a–c
).
Cephalothorax:
2.2 long, 1.4 wide. Carapace oval, blunt anteriorly, caput raised towards anterior, highest at eyes, fovea shallow (
Fig. 20a
); in lateral view carapace projected forward over clypeus (
Fig. 20c
). Labium narrowed anteriorly, about ¾ length of maxillae; chelicerae with basal transverse ridge, retromargin with single tooth, promargin with three teeth; sternum oval, domed with precoxal triangles and with smaller, rounded intercoxal extensions (
Fig. 20b
). Posterior eye row straight, eye group occupying about a third of carapace width (
Fig. 20d
).
Abdomen
: 2.5 long. Covered in fine dense setae (
Fig. 20a
).
Legs:
Leg length ratio: I>II>IV>III. Leg I femur 1.2, patella 0.4, tibia 1.5, metatarsus 1.3, tarsus 0.5. Leg II femur 0.9, patella 0.4, tibia 1.4, metatarsus 1.2, tarsus 0.6. Leg III femur 1.1, patella 0.5, tibia 0.9, metatarsus 0.6, tarsus 0.4. Leg IV femur 1.3, patella 0.5, tibia 1.2, metatarsus 0.7, tarsus 0.4. Femur I bowed in dorsal view. Macrosetae: Leg I: femur dp2ap; tibia p1, pv1-1-1 (long)-1ap, rv1-1-1ap; metatarsus pv1-1-1, rv1-1-1-1ap. Leg II femur dp1ap; tibia dp1-1-2, dp1ap, v1-1-1ap; metatarsus pv1-1-1-1ap, v1, rv1-1-1-1/0ap. Leg IV tibia v1-1; metatarsus r1- 1-1ap, rv1. Retrolateral distal preening comb with 6 spines (
Fig. 20e
). STC I, II with 11 long teeth, ITC with single long tooth, Tarsi with distal ventral scopulose setae.
Pedipalp
tibia short, about 1 ½ the length of the cymbium; cymbium rounded square shape, with anterior prolateral extension; bulb pyramidal in lateral view, embolus elongate, thin and hooked apically (
Fig. 21a–c
).
Variation.
Known only from the
type
specimen.
Distribution.
Known only from
type
locality, Mount Chappell Island in the Furneaux Group (
Fig. 19
).