Ariadna muscosa Hickman 1929
Creators: name: Marsh, Jessica R.
name: Stevens, Mark I.
name: Framenau, Volker W.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Segestriidae
Ariadna
Ariadna muscosa

description: Ariadna muscosa Hickman, 1929
Figs 19, 24a–h, 24a–c
Ariadna muscosa Hickman, 1929: 103–106, figs 3A–C.
Type material. Holotype ♂. AUSTRALIA: Tasmania: Launceston, north Tasmania, 17 May 1928, 41.45°S, 147.17°E, Launceston (QVMAG QVM:13:7339).
Paratype ♀. Same data as holotype (QVMAG QVM:13:7339). Only images examined of paratype and holotype.
Other material examined. Australia: Tasmania: 1 ♂, Launceston, Punchbowl, in moss, 41.45°S; 147.20°E, 01 June 1931 (AM KS.034878); 3 ♂, Launceston, Cataract Gorge, ex pitfall trap, site 4, 41.44°S, 147.11°E; 31 December 2001, Migas plomleyi survey (QVMAG QVM:2020:13:0110).
Diagnosis. Ariadna muscosa is closest to A. crypticola sp. nov., A. ferrogrisea sp. nov. and A. subnubilum sp. nov.. It can be differentiated from A. crypticola sp. nov. by the less pronounced prolateral projection on the cymbium, by the longer and thinner pedipalp tibia and by the embolus, which lacks a defined apical hook in A. muscosa (Fig. 25a–c cf. Fig. 14a–c); it can also be distinguished by having seven macrosetae in the preening comb on metatarsus IV, compared to five macrosetae in A. crypticola sp. nov. Ariadna muscosa can be distinguished from A. ferrogrisea by the pattern and lesser number of macrosetae on the tibia and metatarsus of leg I (Fig. 24f–h cf. Fig. 15f–h) and by the shape of the pedipalp cymbium, which has a more pronounced prolateral extension in A. ferrogrisea sp. nov. (Fig. 25c cf. Fig. 16c). The species can be differentiated from A. subnubilum sp. nov. by the lack of transverse abdominal markings in A. subnubilum sp. nov. (Fig. 24a cf. Fig. 31a); by the greater width compared to length of the pedipalp tibia of A. subnubilum sp. nov. (Fig. 25a, b cf. Fig. 32a, b) and supported by molecular sequencing, with an interspecific divergence of 11.6% (Table 2).
Description. ♂ (based on AM KS.034878). Total length 5.2.
Colour in ethanol: Carapace orange brown, with faint pallid areas extending out from fovea, sparse brown setae. Sternum orange brown, lighter towards the centre; with scattered sparse, long dark setae; labium red, fading to pale cream anteriorly; maxillae and chelicerae red brown.Abdomen dorsally dark grey, with faint, narrow white striations posteriorly, ventrally dark grey, darker medially. Legs golden yellow-brown, with sparse brown setae (Fig. 24a–h).
Cephalothorax: 2.4 long, 1.7 wide. Carapace oval, with a broad neck anteriorly, edges gently undulating and rebordered, fovea a shallow indentation (Fig. 24a), from lateral view carapace raised slightly, highest mid-way between fovea and eye group (Fig. 24c). Labium narrowed anteriorly, about ¾ length of maxillae; chelicerae with basal transverse ridge, retromargin with single tooth, promargin with three teeth; sternum rounded oval, convex, with precoxal triangles and with smaller, broadly triangular intercoxal extensions (Fig. 24b). Posterior eye row recurved, eye group occupying 0.6 of carapace width (Fig. 24d).
Abdomen: 2.8 long; with covering of sparse fine macrosetae (Fig. 24a).
Legs: Leg length ratio: I>II>IV>III. Leg I femur 1.9, patella 0.7, tibia 1.6, metatarsus 1.4, tarsus 0.7; Leg II femur 2.0, patella 0.6, tibia 1.5, metatarsus 0.8, tarsus 0.5; Leg III femur 1.5, patella 0.5, tibia 1.1, metatarsus 0.9, tarsus 0.5; Leg IV femur 1.7, patella 0.7, tibia 1.2, metatarsus 1.0, tarsus 0.5. Femur I bowed in dorsal view. Macrosetae: Leg I femur d1, dp2ap; tibia p1-1, pv1-1-1-1ap, rv1-1-1-1ap, r1-1-1; metatarsus pv1-1-1-1ap, rv1-1-1ap. Leg II femur d1, dp1ap; tibia p1-1-2, pv1ap, rv1-1-1-1ap, r1; metatarsus p1-1-1ap, r1-1-1ap. Leg IV femur d1-1, dp1ap; tibia p1-1, pr1ap, v1-1, metatarsus 1-1-1ap, rv2-1. Retrolateral distal preening comb with 7 spines. STC I, II with 9 teeth (Fig. 24e), ITC with small tooth. Tarsi with sparse distal ventral scopulose setae.
Pedipalp: Tibia 1.4 times the length of the cymbium; cymbium rounded square shape, with not well defined anterior prolateral extension, scopulose setae anteriorly; bulb pyramidal in lateral view, embolus long, thin with slight hook apically (Fig. 25a–c).
Distribution. From localities around Launceston, in northern Tasmania (Fig. 19).
Variation. There was little variation in the material examined. The embolus of each specimen was characteristic, lacking an apical hook.
DNA barcode. A 653 base-pair (bp) fragment of the mitochondrial (mt) DNA cytochrome c oxidase I (COI) gene (DNA barcode) was sequenced for specimen QVM:2020:13:0110 (see other material information above) and is deposited in BOLD (Process ID OZBOL2576-21) and GenBank (accession number ####). The base composition of the DNA barcode sequence is 19.9% A, 40.58% T, 12.86% C and 26.65% G (G + C = 39.51).
Remarks. The holotype and paratype of A. muscosa were examined by images provided by J. Douglas, QVMAG, and could not be measured and examined in detail. We here provide a redescription based on more recently collected material that is representative of this species.
description: Published as part of 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, pp. 151-201 in Zootaxa 5105 (2) on pages 179-182, DOI: 10.11646/zootaxa.5105.2.1, http://zenodo.org/record/6332569