Stephanopis arenata Machado, 2019

Machado, Miguel, Teixeira, Renato Augusto & Milledge, Graham A., 2019, On the Australian Bark Crab Spider Genus Stephanopis: Taxonomic Review and Description of Seven New Species (Araneae: Thomisidae: Stephanopinae), Records of the Australian Museum 71 (6), pp. 217-276 : 228-230

Stephanopis arenata Machado sp. nov.

http://zoobank.org/NomenclaturalActs/ 308FC57E-3514-4687-804B-C623DBF5A92C

Figs 6–7

Holotype ♀, AMS KS.128001, Scotia Sanctuary , New South Wales, Australia, 33°07'36"S 141°10' 40"E, H. Gibb, February 2009, (designated here) . Paratypes: AMS KS.66762, 1♂, Lower Murray-Darling Region (Warrakoo Station), New South Wales, Australia, 33°51'16"S 141°07'06"E, M. Lebreton, 12–16 October 1998 ; AMS KS.50784, 1♂, Simpson Desert (Ethabuka station), Queensland, Australia, 23°45'S 138°28'E, H. Wilson, July 1997 .

Other material examined. Queensland: QM S35214 , 2♀♀, Westmar, 27°54'45.98"S 149°2'30.56"E, V. Davies, T. Adams & R. Raven, 10 January 1979 . Western Australia:

WAM T130261 , 1♀, 16.5 km southeast of Pannawonica Fortescue River Valley , 21°41'38"S 116°28'24"E, F. Bokhari, 10 September 2012 ; WAM T146672 , 1♀, Goldfields Survey (dune shrubland), 32°23'15"S 119°45'00"E .

Diagnosis. Females of S. arenata sp. nov. and S. cambridgei have a predominantly orange body colouration and the external shape of their epigynum is similar, with CO hidden by the lateral folds of the plate ( Fig. 6A, C and D ). Still, females of S. arenata sp. nov. can be distinguished from S. cambridgei by their complete atrium delimited anteriorly by the folds of the epigynal plate, and copulatory ducts sclerotized and not coiled. Males are similar to those of S. cambridgei due to their striped legs ( Fig. 7A ), single and curved RTA ( Fig 7C and 7D ) and the tibiae and metatarsi I bearing long and thin barbs ( Fig 7A ); male palp can be also distinguished by the bent/tilted cymbium and shorter embolus ( Fig. 7C ). Moreover, as this species occurs in desertic areas, it can be undoubtedly recognized due to the grains of sand, rock fragments and other soil particles attached to their bodies ( Figs 6A and 7A ).

Description. Female (AMS KS.128001): Anterior eyes arranged in a strongly recurved row and posterior eyes in straight row; cephalic area narrowed ( Fig. 6A and B ); body predominantly dark orange and covered in grains of sand and thick bacillar setae. Legs striped; femur I with pair of prolateral macrosetae. Opisthosoma slightly wider than long and copulatory ducts asymmetrically coiled; anterior chamber absent and glandular-heads reduced, dorsally oriented ( Fig. 6D ).

Measurements: eye diameters and interdistances: AME 0.06, ALE 0.12, PME 0.10, PLE 0.10, AME–AME 0.08, AME–ALE 0.04, PME–PME 0.14, PME–PLE 0.12, MOQ length 0.36, width 0.28; leg formula: 1-2-4-3: leg I—femur 3.39/ patella 1.07/ tibia 2.20/ metatarsus 1.26/ tarsus 0.65/ total 8.57; II—1.89/ 0.79/ 1.40/ 1.13/ 0.44 5.65; III—1.23/ 0.55/ 1.64/ 0.61/ 0.52/ 4.55; IV—1.75/ 0.62/ 1.14/ 1.11/ 0.63/ 5.25. Total body length 5.97; prosoma length 2.59, width 2.37; opisthosoma length 3.38; clypeus height 0.47; sternum length 1.16, width 1.16; gnathocoxae length 0.43, width 0.24; labium length 0.25, width 0.39.

Male (AMS KS.66762): Prosoma and opisthosoma lightorange ( Fig. 7B ), leg segments (except tibiae, metatarsi and tarsi I and II) yellow with dark-brown annuli ( Fig. 7A ); Pcym reduced, hyaline and placed at same height as tip of the RTA ( Fig. 7C ). Other somatic features as in female.

Measurements: eye diameters and interdistances: AME 0.07, ALE 0.18, PME 0.09, PLE 0.10, AME–AME 0.11, AME–ALE 0.05, PME–PME 0.16, PME–PLE 0.16, MOQ

length 0.32, width 0.23; leg formula: 1-2-4-3: leg I—femur 3.23/ patella 1.11/ tibia 3.26/ metatarsus 1.94/ tarsus 0.73/ total 10.27; II—2.26/ 0.79/ 1.94/ 1.44/ 0.71/ 7.14; III—1.45/ 0.60/ 1.05/ 0.86/ 0.57/ 4.53; IV—2.28/ 0.68/ 1.59/ 1.48/ 0.67/ 6.70. Total body length 7.14; prosoma length 2.63, width 2.41; opisthosoma length 2.75; clypeus height 0.44; sternum length 1.14, width 1.16; gnathocoxae length 0.48, width 0.29; labium length 0.38, width 0.40.

Etymology. The specific epithet derives from the feminine Latin noun “ arena ”, which means sand; the word “ arenata ” means covered with sand.

Distribution. Western Australia and New South Wales, Australia ( Fig. 13 ).

Figures

Figure 6. Stephanopis arenata sp. nov., female (KS.128001). (A) dorsal habitus; (B) front; (C) epigynal plate, ventral view; (D) epigynal plate/spermathecae.

Figure 7. Stephanopis arenata sp. nov., male (KS.66762). (A) dorsal habitus; (B) front; (C) ventral view of the left palp; (D) left palp, retro lateral view.

Figure 13. Distribution records of Stephanopis altifrons, S. angulata, S. arenata sp. nov., S. armata and S. barbipes.