Ariadna subnubilum, Marsh & Stevens & Framenau, 2022

Marsh, Jessica R., Stevens, Mark I. & Framenau, Volker W., 2022, A taxonomic revision of the tube-web spiders of the genus Ariadna (Araneae: Segestriidae) in Tasmania, Zootaxa 5105 (2), pp. 151-201 : 186-189

publication ID	https://doi.org/ 10.11646/zootaxa.5105.2.1
publication LSID	lsid:zoobank.org:pub:4F6F5BC6-2AAF-4B23-882E-F77C63BE4CC2
DOI	https://doi.org/10.5281/zenodo.6335881
persistent identifier	https://treatment.plazi.org/id/485DAE32-C304-4F07-9290-BF7860D29343
taxon LSID	lsid:zoobank.org:act:485DAE32-C304-4F07-9290-BF7860D29343
treatment provided by	Plazi
scientific name	Ariadna subnubilum
status	sp. nov.

Treatment

Ariadna subnubilum sp. nov. (TMAG J6266)

Figs 31a–h View FIGURE 31 , 32a–c View FIGURE 32 , 33 View FIGURE 33

http://zoobank.org/NomenclaturalActs/485dae32-c304-4f07-9290-bf7860d29343

Type material. Holotype ♂. AUSTRALIA: Tasmania: 5km ENE McPartlan Pass , 42.83796°S, 146.24072°E, 350m, February 2002, pitfall trap, coll. D. Driscoll ( TMAG J6266 View Materials ). GoogleMaps

Other material examined. Known only from the type specimen.

Etymology. The specific epithet is a Latin adjective, meaning ‘somewhat overcast’ and refers to the mottled light and dark grey colour of the species’ abdomen.

Diagnosis. Ariadna subnubilum sp. nov. is most similar to A. crypticola sp. nov., A. ferrogrisea sp. nov. and A. muscosa . Ariadna subnubilum sp. nov. is differentiated from A. crypticola sp. nov. by having a squarer cymbium, with a less well defined prolateral extension than in A. crypticola sp. nov. ( Fig. 32c View FIGURE 32 cf. Fig. 14c View FIGURE 14 ), and by the lack of a transverse abdominal pattern ( Fig. 31a View FIGURE 31 cf. Fig. 13a View FIGURE 13 ). It can be differentiated from A. ferrogrisea sp. nov. by the pattern and number of macrosetae on tibia and metatarsus of leg I, which are denser in A. ferrogrisea sp. nov. ( Fig. 31 View FIGURE 31 f-h cf. Fig. 15f–h View FIGURE 15 ), by the lack of transverse abdominal markings in A. subnubilum sp. nov. ( Fig. 31a View FIGURE 31 cf. Fig. 15a View FIGURE 15 ) and by the shape of the pedipalp bulb, which is pyramidal in A. ferrogrisea sp. nov., but is rounded oblong in A. subnubilum sp. nov. ( Fig. 32a, b View FIGURE 32 cf. Fig. 16a, b View FIGURE 16 ). The species can be distinguished from A. muscosa by the lack of transverse abdominal markings in A. subnubilum sp. nov. ( Fig. 31a View FIGURE 31 cf. Fig. 24a View FIGURE 24 ); by the greater width compared to length of the pedipalp tibia of A. subnubilum sp. nov. ( Fig. 32a, b View FIGURE 32 cf. Fig. 25a, b View FIGURE 25 ) and molecular sequencing, with an interspecies divergence of 11.6% ( Table 2 View TABLE 2 ).

Description. ♂ (based on holotype; TMAG J6266). Total length 4.6.

Colour in ethanol: Carapace dark red brown, darker anteriorly; with sparse, scattered dark setae, denser anteriorly. Sternum mid red brown, with black long brown setae. Maxillae and labium mid brown, paler in colour apically; chelicerae dark red brown. Abdomen dorsally light grey with mottled darker grey patches; ventrally same. Legs golden yellow brown, with dark setae ( Fig. 31a–h View FIGURE 31 ).

Cephalothorax: 2.4 long, 1.6 wide. Carapace broadly oval, anteriorly with broad neck, caput raised towards anterior, fovea shallow ( Fig. 31a View FIGURE 31 ); in lateral view highest at midpoint between fovea and eyes ( Fig. 31c View FIGURE 31 ). Labium narrowed anteriorly, about ¾ length of maxillae; chelicerae semi-porrect, with basal transverse ridge, retromargin with single tooth, promargin with three teeth; sternum rounded oval, with precoxal triangles and with smaller, rounded intercoxal extensions ( Fig. 31b View FIGURE 31 ). Posterior eye row slightly recurved, eye group on prominent extension projecting anteriorly over clypeus, eye group occupying 0.6 of carapace width.

Abdomen: 2.2 long; with a covering of dense, fine setae ( Fig. 31a View FIGURE 31 )

Legs: Leg length ratio: I>II>IV>III. Leg I femur 2.4, patella 0.8, tibia 2.1, metatarsus 2.1, tarsus 0.9. Leg II femur 2.2, patella 0.7, tibia 2.2, metatarsus 1.9, tarsus 1.0. Leg III femur 1.5, patella 0.5, tibia 1.5, metatarsus 1.4, tarsus 0.7. Leg IV femur 2.0, patella 0.6, tibia 1.5, metatarsus 1.4, tarsus 0.6. Leg I Femur I bowed in dorsal view. Macrosetae: leg I femur d1-1-1-1ap, dp2ap; tibia p1-1-1-1-1, pv1-1-1-1-1ap, v1-1-1-1, rv1-1-1-1-1ap, r1-1-1-1-1-1; metatarsus pv1-1-1-1-1-1ap, rv1-1-1-1, r1. Leg II femur d1-1-1-1ap, dp1ap; tibia pv1-1-1, v1-1-1ap, rv1-1-1-1-1- 1-1-1-1ap, r1-1-1-1-1; metatarsus p1, pv1-1-1-1-1-1ap, rv1-1-1-2ap, r1. Leg IV femur d1-1-1-1, dp1ap; tibia p1-1, pv1-1-1ap, rv1-1; metatarsus p1, rv1-1-1-1ap, r1. Retrolateral distal preening comb with 7 spines ( Fig. 31e View FIGURE 31 ). STC I, II with 9 long teeth, ITC with single tooth, Tarsi with sparse distal ventral scopulose setae.

Pedipalp: Tibia short, bulbous and ventrally expanded, about 1 1/2 the length of the cymbium; cymbium rounded square, with prolateral triangular extension, apically with elongate setae; bulb rounded oblong, embolus originating from ventral edge of bulb, quite broad, curved and hooked apically ( Fig. 32a–c View FIGURE 32 ).

Variation. Known only from the type specimen.

Distribution. Known only from McPartlan Pass, northwest Tasmania ( Fig. 33 View FIGURE 33 ).

DNA barcode. A 655 base-pair (bp) fragment of the mitochondrial (mt) DNA cytochrome c oxidase I ( COI) gene (DNA barcode) was sequenced for specimen TMAG J6266 View Materials (see Holotype information above) and is deposited in BOLD (Process ID OZBOL2584-21 ) and GenBank (accession number ####). The base composition of the DNA barcode sequence is 21.07% A, 40.15% T, 13.59% C and 25.19% G (G + C = 38.78%) .