Missulena davidi, Greenberg & Huey & Framenau & Harms, 2021

Greenberg, Marleen R., Huey, Joel A., Framenau, Volker W. & Harms, Danilo, 2021, Three new species of mouse spider (Araneae: Actinopodidae: Missulena Walckenaer, 1805) from Western Australia, including an assessment of intraspecific variability in a widespread species from the arid biome, Arthropod Systematics & amp; Phylogeny 79, pp. 509-533 : 509

3.1. Missulena davidi sp. nov.

Figs 3 , 4 , 5 , 6 , 7

Type material.

Holotype: AUSTRALIA - Western Australia • ♂; Juna Downs Station, 113 km NW of Newman; 22°41.23′S 118°53.55′E; 10 May 2011; C. Cole and P. Runham leg.; pit trap; WAM T119725 • Allotype: AUSTRALIA - Western Australia • ♀; Hope Downs, 73.7 km NW of Newman; 20°59.42′S 119°7.3′E; 27 June 2010; G. Humphreys and P. Runham leg.; dug from burrow; WAM T107393 • Paratypes: AUSTRALIA - Western Australia • 1♀; same data as holotype; 22°41.18′S 118°53.58′E; dug from burrow; WAM T119711 • 1♀; Juna Downs Station, 114 km NW of Newman; 22°43.55′S 118°50.98′E; 12 May 2011; P. Runham leg.; dug from burrow; WAM T119718 • 1♂; Juna Downs Station, 116 km NW of Newman; 22°38.73′S 118°54.17′E; 11 May 2011; C. Cole and P. Runham leg.; pit trap; WAM T119726 • 1♂; same data as for preceding; WAM T119727 • 1♂; same data as for preceding; 10 May 2011; WAM T119728 • 1♂; same data as for preceding; WAM T119729 • 1♂; same data as for preceding; 117 km NW of Newman; 22°37.73′S 118°54.1′E; WAM T119731 • 1♂; same data as for preceding; 22°36.63′S 118°56.38′E; G. Humphreys and J. Tatler leg.; WAM T119733.

Other material examined.

AUSTRALIA - Western Australia • 1♀; Carnarvon, 99 Gascoyne Road ; 24°53′S 113°39′E; 23 July 2002; residents leg.; by hand; WAM T46798 • 1♂; Cloudbreak Mining Lease, Fortescue Metals Group (site 25); 22°20.1′S 119°24.23′E; 6 Sept. 2006; S. Thompson leg.; WAM T84005 • 1♀; Jimblebar minesite, 35 km E of Newman; 23°22.5′S 120°12.58′E; 6 Feb. 2009; P. Bolton and C. Weston leg.; active search; WAM T95397 • 1♀; Murray Hills, Mulga Downs Station, Ecologia project 1142; 22°07.67′S 118°30.92′E; 19 Apr. 2009; N. Dight and L. Quinn leg.; dry pitfall trap; WAM T97637 • 1♀; Davidson Creek , ca. 75 km E of Newman, vert site 6; 23°25.73′S 120°26.8′E; 9 Apr. 2010; J. Clark leg.; dry pitfall; WAM T102165 • 1♀; South Parmelia , 52 km NW of Newman; 23°5.13′S 119°19.08′E; 16 Apr. 2011; R. Teale and M. Greenham leg.; dug from burrow; WAM T113591 • 1♂; Southern Flank , 72 km NW of Newman; 23°0.17′S 119°8.37′E; 14 Apr. 2011; R. Teale and M. Greenham leg.; dug from burrow; WAM T113596 • 1♂; same locality; 23°0.18′S 119°8.35′E, 14 Apr. 2011; R. Teale and M. Greenham leg.; dug from burrow; WAM T113598 • 1♀; 113.8 km NW of Newman ; 22°39.39′S 118°55.09′E; 26 May 2011; M. Greenham and R. Teale leg.; dug from burrow; WAM T113626 • 1♀; 119.1 km NW of Newman ; 22°38.02′S 118°52.19′E; 30 May 2011; M. Greenham and R. Teale leg.; dug from burrow; WAM T113660 • 1♀; 117.6 km NW of Newman ; 22°37.66′S 118°53.76′E; 31 May 2011; M. Greenham and R. Teale leg.; dug from burrow; WAM T113665 • 1♀; Mudlark , 107 km W of Newman; 23°5.63′S 118°43.17′E; 30 June 2011; C. Cole and N. Watson leg.; dug from burrow; WAM T116746 • 1♀; Mudlark , 111 km WNW of Newman; 23°5.2′S 118°41.18′E; 30 June 2011; M. Greenham and J. Cairnes leg.; dug from burrow; WAM T116751 • 1♀; same data as for preceding; 23°5.22′S 118°41.17′E; WAM T116755 • 1♀; Mudlark , 113 km W of Newman; 23°2.28′S 118°40.97′E; 1 July 2011; M. Greenham and J. Cairnes leg.; dug from burrow; WAM T116776 • 1♀; Mudlark , 102 km W of Newman; 23°5.4′S 118°48.67′E; 3 July 2011; C. Cole and N. Watson leg.; dug from burrow; WAM T116839 • 1♀; Mudlark, 94 km W. of Newman ; 23°4.78′S 118°51.48′E; 6 July 2011; M. Greenham and J. Cairnes leg.; dug from burrow; WAM T116866 • 1♀; same locality; 23°4.77′S 118°51.47′E; 26 July 2011; C. Cole and N. Watson leg.; dug from burrow; WAM T116868 • 1♀; 84.2 km NW of Newman ; 22°40.5′S 119°20.95′E; 26 July 2011; D. Kamien, M. Greenham and Z. Hamilton leg.; dug from burrow; WAM T116873 • 1♀; same data as for preceding; 22°40.48′S 119°20.9′E; WAM T116874 • 1♀; same data as for preceding; 89.3 km NW of Newman ; 22°38.45′S 119°19.23′E; WAM T116875 • 1♀; same data as for preceding; 89.3 km NW. of Newman ; 22°38.45′S 119°19.22′E; WAM T116881 • 1♀; Mulga Downs Station, Cowra , site 994-13; 22°13.63′S 119°0.82′E; 16 Apr. 2012; WAM T118328 • 1♀; 84.8 km NW of Newman ; 22°40.1′S 119°22.48′E; 27 July 2011; D. Kamien, M. Greenham and Z. Hamilton leg.; dug from burrow; WAM T119975 • 1♀; same data as for preceding; 99.1 km NW of Newman ; 22°34.3′S 119°17.15′E; WAM T119979 • 1♀; same data as for preceding; 22°34.3′S 119°17.17′E; WAM T119980 • 1♀; 105.3 km NW of Newman ; 22°30.72′S 119°15.55′E; 28 July 2011; D. Kamien, M. Greenham and Z. Hamilton leg.; dug from burrow; WAM T119984 • 1♀; same data as for preceding; 22°30.72′S 119°15.53′E; WAM T119993 • 1♀; 81.2 km NW of Newman ; 22°42.02′S 119°22.68′E; 29 July 2011; D. Kamien, M. Greenham and Z. Hamilton leg.; dug from burrow; WAM T119995 • 1♀; 85.2 km NW. of Newman ; 22°39.2′S 119°24.82′E; 31 July 2011; D. Kamien, M. Greenham and Z. Hamilton leg.; dug from burrow; WAM T120018 • 1♀; same data as for preceding; 22°39.2′S 119°24.83′E; WAM T120019 • 1♂; same data as for preceding; 18.9 km NE of Tom Price ; 22°39.2′S 119°24.82′E; WAM T120081 • 1♀; Koodaideri Corridor West , 93.7 km NE of Tom Price; 22°19.7′S 118°36.61′E; 20 Feb. 2012; C. Cole leg.; burrow search; WAM T122209 • 1♀; same data as for preceding; 89.4 km NE of Tom Price ; 22°15.92′S 118°31.3′E; WAM T122217 • 1♀; same data as for preceding; 71.7 km NE of Tom Price ; 22°8.12′S 118°8.17′E; WAM T122224 • 1♀; same data as for preceding; 70.1 km NE of Tom Price ; 22°9.31′S 118°8.07′E; WAM T122226 • 1♀; same data as for preceding; 22°9.37′S 118°8.07′E; leaf litter rake; WAM T122235 • 1♀; same data as for preceding; 82.1 km NE of Tom Price ; 22°13.95′S 118°24.88′E; burrow search; WAM T122252 • 1♀; same data as for preceding; 77.3 km NE of Tom Price ; 22°1.68′S 118°0.22′E; WAM T122254 • 1♀; 111.6 km NW of Newman ; 22°53.52′S 118°45.89′E; 29 Mar. 2012; C. Cole and N. Watson leg.; dug from burrow; WAM T122822 • 1♀; 115.4 km NW of Newman ; 22°54.52′S 118°43.05′E; 31 Mar. 2012; C. Cole and N. Watson leg.; dug from burrow; WAM T122843 • 1♀; 118.6 km NW of Newman ; 22°52.85′S 118°41.22′E; 1 Apr. 2012; N. Watson and P. Brooshooft leg.; dug from burrow; WAM T122865 • 1♀; 124 km NW of Newman ; 22°51.93′S 118°38.47′E; 1 Apr. 2012; N. Watson leg.; dug from burrow; WAM T122872 • 1♂; 63.5 km ESE of Paraburdoo , site 1000-tur01; 23°17.31′S 118°17.1′E; 27 Apr. 2012; E.S. Volschenk leg.; wet pitfall; WAM T125176 • 1♀; Koodaideri Western Corridor , 217.5 km NW of Newman; 22°7.71′S 118°5.57′E; 28 Mar. 2012; G. Humphreys and M. Greenham leg.; dug from burrow; WAM T125307 • 1♀; same data as for preceding; 194.8 km NW of Newman ; 22°7.71′S 118°7.71′E; WAM T125308 • 1♀; Koodaideri Western Corridor , 214 km NW of Newman; 22°8.14′S 118°6.46′E; 29 Mar. 2012; G. Humphreys and J. King leg.; dug from burrow; WAM T125316 • 1♀; 118.2 km NW of Newman ; 22°36.32′S 118°55.15′E; 19 Nov. 2011; M. Greenham and Z. Hamilton leg.; WAM T126257 • 1♀; 118.3 km NW of Newman ; 22°36.67′S 118°54.43′E; 18 Nov. 2011; M. Greenham and Z. Hamilton leg.; WAM T126260 • 1♀; same data as for preceding; WAM T126264 • 1♀; 114 km NW of Newman ; 22°36′54″S 118°57′18″E; 21 Nov. 2011; M. Greenham and Z. Hamilton leg.; WAM T126272 • 1♀; same data as for preceding; 22°36.87′S 118°57.3′E; WAM T126276 • 1♀; Karijini National Park , ca. 20 km SW of Hancock Gorge; 22°29.03′S 118°8.85′E; 15 Mar. 2015; C. Stevenson, M.S. Harvey and M. Hillyer leg.; WAM T135548 • 1♀; Karijini National Park, ca. 25 km SSW. of Dales Gorge ; 22°39.48′S 118°26.05′E; 17 Mar. 2015; M.S. Harvey et al. leg.; WAM T135563 • 1♀; Karijini National Park , ca. 6 km NW of Mt Bruce; 22°34.12′S 118°5.98′E; 15 Mar. 2015; J. Huey et al. leg.; WAM T135591 .

Diagnosis.

Males of Missulena davidi sp. nov. share the red colouration of chelicerae and pars cephalica with M. langlandsi Harms and Harvey, 2013, M. occataria Walckenaer, 1805, M. insignis O. Pickard-Cambridge, 1877, M. iugum sp. nov. and M. manningensis sp. nov. that are morphologically most similar. They differ from M. langlandsi by having strong, conical spines of the rastellum (thin and not conical in the former) and a longer carapace (>3.00 mm; M. langlandsi up to 2.8 mm). They differ from M. occataria and M. insignis by having spines on patellae III and IV only and not on all four legs (on patellae I and II 1 spine, respectively). Missulena davidi sp. nov. males have more cuspules on maxillae and labium than those of M. manningensis sp. nov. ( M. manningensis sp. nov.: 5 at labium, 30 at maxillae; M. davidi sp. nov.: 15-10 at labium, 35-100 at maxillae). Missulena davidi sp. nov. males differ from M. iugum sp. nov. by the ridge present in the cheliceral groove. Females of Missulena davidi sp. nov. have uniformly red chelicerae that they share with M. insignis ; however, the fourth leg of M. davidi sp. nov. is the longest of all legs, whilst in M. insignis the longest leg is the first. Additionally, there are no cuspules recorded on the labium or the maxillae in M. insignis females.

Description.

MALE (based on holotype; WAM T119725). Total length 9.8. Colour: pars cephalica and chelicerae reddish-orange (Fig. 3C ); a slim, black ring surrounding the PME (Fig. 4E ); pars thoracica brown with a light, metallic blue sheen (Fig. 3C ); abdomen greyish with a strong, metallic blue sheen on the dorsal side, ventrally more brownish with a faint hint of purple (Fig. 3D, E ); sternum orange, slightly fading into olive with 8 sigilla in similar colour (Fig. 4D ); labium and maxillae orange with a dark olive spot on the base of labium (Fig. 3F ); legs olive-yellowish fading into light brown ventrally, dorsally brown (Fig. 3A, B ); spinnerets beige-coloured (Fig. 3E ). Carapace: 3.86 long and 4.67 wide; clypeus 0.31; pars cephalica covers 2.45 of its length, is highly elevated and slightly granulated with very few setae (Fig. 3G ); pars thoracica also granulated with bands of faint, radial fissures and with two notches close to the abdomen (Fig. 3C ). Eyes: OQ 4 times wider than long; outer width of each eye pair AME 0.66, ALE 2.44, PME 1.48 and PLE 2.21; diameter of AME 0.19, ALE 0.22, PME 0.15, PLE 0.19; anterior eyes very slightly recurved; posterior eyes strongly recurved (Fig. 4E ). Chelicerae: 2.04 long and 1.47 wide on the base; edges rounded and recurved with the widest point being 1.55 close to the chelicerae base (Fig. 3C ); small, faint files along the outer margin of each chelicera; evenly spread setae along the inner margin and the anterior part of the chelicerae; rastellum present, slightly pronounced, consisting of a sclerotized process with 7 (left 8) strong, conical spines (Fig. 4F ); over 25 setae cover the anterior base of fang of each chelicera; inner margin of cheliceral furrow with 2 rows of teeth and a general cheliceral teeth area in between those 2 clear rows (Fig. 4A, J ); prolateral row with approx. 9 teeth; retrolateral row with 4 teeth; intermediate area with 10 small teeth. Maxillae: 2.08 long and 1.44 wide; at least 80-100 weakly developed cuspules along entire anterior margin (Fig. 3F ). Labium: 0.96 long and 0.86 wide on the base; conical; at least 40 weakly developed cuspules anteriorly (Fig. 3F ); labiosternal junction visible (Fig. 4D ). Sternum: 2.6 long and 2.38 wide; ovoid (Fig. 4D ); setae of various length somewhat densely but disordered along the margin and a smaller amount of setae spread unevenly over the sternum; 4 pairs of sigilla, anterior pair smallest and hardly visible, second pair also very small and circular, third pair significantly larger than second (roughly 5 times bigger) in the shape of an elongated oval, and posterior pair biggest (roughly 1.5 times the size of the third pair) in the shape of a drop, all sigilla slightly depressed. Abdomen: 3.88 long and 3.4 wide; shape of a rounded trapezoid (Fig. 3D ); 4 spinnerets, PLS 1.12 long, 0.48 wide; PMS 0.43 long, 0.23 wide. Pedipalp: length of trochanter 1.49, femur 3.68, patella 1.68, tibia 4.01, tarsus 0.72; all segments with setae, tibia ventrally covered with comparably long setae (Fig. 4I ); tibia rather thin and slightly recurved, 1.00 wide on the widest point from dorsal and prolateral view (Fig. 4G-I ); bulb roughly pyriform (Fig. 4G-I ), two strongly sclerotized sections connected by a velar median structure ( “haematodocha”); embolus short with an intumescence in proximal region; tip of embolus triangular with a small lamella and a tooth best visible from prolateral view (paratype, Fig. 3H, I ). Legs: brown setae of various sizes on all sides of the legs and bent strongly towards the exterior with the exceptions of some long, dorsal setae on tibia I and IV; ventral preening comb on tarsi and metatarsi III and IV. Leg spination: leg I: tibia rv0, v5, pl0, d0; metatarsus rv3, v8, pl2, d0; tarsus rv3, v3, pl4, d0; leg II: tibia rv0, v8, pl0, d0; metatarsus rv0, v11, pl0, d0; tarsus rv3, v3, pl2, d0; leg III: tibia rv4, v8, pl0, d11; metatarsus rv4, v11, pl0, d11; tarsus rv5, v9, pl4, d5; leg IV: tibia rv0, v5, pl0, d0; metatarsus rv0, v16, pl0, d2; tarsus rv4, v10, pl3, d3; patella I with one spine prolateral close to the tibia and patella II with one spine ventrally also close to the tibia; patella III with ca. 23 spines prolateral to dorsal (Fig. 4B ), 1 spine retrolateral; patella IV with one spine dorsal close to the tibia and approx. 12 small spines (Fig. 4C ) and ca. 18 prolateral, also very small. Leg measurements: Leg I: femur 3.72, patella 1.29, tibia 2.72, metatarsus 2.37, tarsus 1.37, total 11.47. Leg II: femur 3.31, patella 1.36, tibia 2.43, metatarsus 2.26, tarsus 1.38, total 10.74. Leg III: femur 2.72, patella 1.26, tibia 1.93, metatarsus 1.92, tarsus 1.35, total 9.18. Leg IV: femur 3.45, patella 1.47, tibia 2.76, metatarsus 2.41, tarsus 1.51, total 11.6. Formula: 4>1>2>3.

FEMALE (based on allotype; WAM T107393). Total length 23.9. Colour: Carapace brown (Fig. 5A ); chelicerae reddish-orangish with a darker spot (dark reddish-brown) on each chelicerae base (Fig. 5A ); eye region light reddish colour similar to chelicerae (Fig. 5A ); abdomen greyish-brown with a faint, dorsal, metallic blue sheen (Fig. 5B ); sternum light brown fading into a reddish-brown towards labium (Fig. 5C ), sigilla darker brown (Fig. 5C ); labium und maxillae reddish-brown (Fig. 5E ); legs brown (Fig. 5F, G ); spinnerets lighter brown (Fig. 5B ). Carapace: 7.31 long and 9.88 wide; clypeus 0.74; pars cephalica covers 4.72 of its length, is highly elevated and smooth (Fig. 5D ) with some setae going along the margin of the chelicerae as well as vertically in a line from the AME to fovea plus some random setae (Fig. 5A ); pars thoracica smooth surface with bands of faint, radial fissures (Fig. 5A ). Eyes: OQ 4.9 times wider than long; width of each eye pair AME 0.91, APE 6.01, PME 3.59 and PLE 5.54; diameter of AME 0.33, ALE 0.36, PME 0.25, PLE 0.3; anterior eyes in one straight line; posterior eyes clearly recurved (Fig. 5H ). Chelicerae: 5.65 long and 4.15 wide on the base; edges rounded and recurved with the widest point being 4.73 close to the chelicerae base (Fig. 5A ); long setae along the inner margin increasing in amount towards rastellum; short and fewer setae along the outer margin and no setae in centre (Fig. 5A ); rastellum present with 10-14 conical spines on each chelicera and long, densely disordered setae (Fig. 5I ); approx. 25 setae cover anterior base of fang; inner margin of cheliceral furrow with two main rows of cheliceral teeth and a small cheliceral teeth area in between (Fig. 6F ); prolateral row with 11 teeth, the first 3 teeth next to the fang’s base are partially grown together; retrolateral row with 10 teeth; intermediate area with approx. 32 small teeth. Maxillae: 4.48 long and 3.67 wide; at least 150-170 strongly developed cuspules along entire anterior margin (Fig. 5E ). Labium: 4 long and 2.27 wide on the base; conical; at least 60 cuspules (Fig. 5E ); anterior pair of sigilla reach labiosternal junction; labiosternal junction clearly developed (Fig. 5C ). Sternum: 6.32 long and 5.7 wide; oval (Fig. 5C ); setae of various length somewhat densely but disordered along the margin and a similar amount of setae of various sizes spread evenly over the sternum; 4 pairs of sigilla, anterior pair small and hardly visible, second pair (anterior-posterior) smallest and divided in circles, third pair larger than second and roughly in the shape of an elongated oval, and posterior pair biggest (roughly 4 times the size of the third pair); all sigilla depressed, two anterior pairs just slightly, two posterior pairs strongly. Abdomen: 10.87 long and 9.12 wide; surface covered with horizontal wrinkles and dense setae (Fig. 5B ); PLS 2.84 long and 1.5 wide; PMS 1.43 long and 0.6 wide. Pedipalp: Length of trochanter 1.5, femur 4.62, patella 1.79, tibia 3.23, tarsus 2.96; approx. 17 spines spread prolateral, retrolateral and ventral on tarsus. Genitalia: one pair of simple and rounded spermathecae, sperm ducts relatively short (Fig. 6A-E ). Legs: densely covered in brown setae of various sizes on all sides of the legs and bent towards the exterior with the exceptions of some long, dorsal setae on tibia, metatarsus and tarsus. Leg spination: leg I: tibia rv0, v0, pl0, d0; metatarsus rv1, v2, pl0, d0; tarsus rv6, v13, pl6, d0; leg II: tibia rv0, v0, pl0, d0; metatarsus rv1, v3, pl0, d0; tarsus rv6, v11, pl3, d0; leg III: tibia rv1, v0, pl2, d8; metatarsus rv0, v1, pl0, d18; tarsus rv7, v11, pl7, d6; leg IV: tibia rv0, v0, pl1, d5; metatarsus rv0, v3, pl4, d2; tarsus rv1, v15, pl9, d3; patellae I and II aspinose; patella III with ca. 28 spines prolateral to dorsal (Fig. 5F ); patella IV with ca. 18 spines prolateral to dorsal (Fig. 5G ). Leg measurement: leg I: femur 5.2, patella 2.16, tibia 3.4, metatarsus 2.5, tarsus 1.93, total 15.19. leg II: femur 5.32, patella 2.54, tibia 3.02, metatarsus 2.86, tarsus 2.04, total 15.78. leg III: femur 5.03, patella 2.64, tibia 2.39, metatarsus 3.08, tarsus 2.15, total 15.29. leg IV: femur 5.6, patella 2.61, tibia 3.66, metatarsus 3.31, tarsus 2.24, total 17.42. Formula: 4>2>3>1.

Etymology.

The specific epithet is a patronym in honour of the senior author’s husband, David A. Greenberg.

Distribution.

Pilbara region of Western Australia, excluding the northern Pilbara subregion, extending into the Little Sandy Desert region. The known linear range of this species is 295 km (Fig. 7 ).

Genetic structure.

The species is highly structured across its range with four genetic clades that have sympatric distributions (Figs 2 , 7 ).

Remarks.

This species had been labelled “MYG045” in previous barcoding studies ( Castalanelli et al. 2014).

Variability.

Assessment of 19 characters in male M. davidi sp. nov. and 18 characters in females (Table 1 ) highlights substantial variation in many characters within and between sampling localities, in both the male and female specimens examined.

In both sexes there is substantial variation in body colouration. In males, the chelicera and pars cephalica ranged from a bright red (specimen WAM T119729; Fig. 13A ) to a red with a shade of orange (male: T120081; Fig. 13B ) whereas abdominal colour in dorsal varied between green, purple and blue metallic tones to no metallic sheen at all (Fig. 13G-H ). Colouration of the pars thoracica ranged from light brown (T119733) to nearly black (T119731) and the orange to olive transition on the sternum and coxa was also highly variable (compare T84005; Fig. 13F with T113596; Fig. 13E ). In females, cheliceral colouration ranged between dark red (T116874; Fig. 14A ) to a light orange (T119979 or T116776; Fig. 14B ). The abdomen in some specimens had a metallic sheen and the sternum varied between uniformly orange (T116776; Fig. 14F ) to a full transition from orange to dark red (T119711; Fig. 14G ). Colour of legs and pars thoracica ranged between light brown (T116776) to dark brown (T125308). The colour variations still hold true if considering possible artefacts of preservation, i.e. varying trapping liquids, ethanol concentration during storage, and time of preservation.

Variability was also high in rastellum spination and cuspule counts. Some male specimens had about twice as many rastellum spines (Fig. 13L, M ) and/or cuspules on both maxillae and labium than others. Female variability was even higher with some specimens having up to four times more maxillary cuspules (Fig. 14H, I ) or nearly five times more spines on the rastellum (17; Fig. 14N, O ) than others. The spination of the patellae was also variable which included spinal counts, size, and positioning of the individual spines. While male specimens showed variation on the first, third and fourth patella, females only had spines on the third and fourth patella (see Table 1 for details). The shape of the sternum in females varied considerably between ovoid and round, and the shape, size and position of the sternal sigilla differed substantially (Fig. 14F, G ). The second pair of sigilla was subdivided into two depressions in some female specimens but not in others. Variation in body size was also substantial (Fig. 15 ) and the carapace length ranged from 3.58 to 4.74 in males and 5.12 to 8.97 in females.

Eye ratio of the PLE and PME pair width in relation to the ALE pair width varied less than other characters. While still showing variation in males and females its range was less extreme (within 8% in males and 16% in females) than in other characters (Figs 13I-K , 14J-M ; see boxplot Fig. 16 ). Male bulb structure also varied little (Fig. 3 H, I ).

There was no correlation between geographical distance of samples and morphological divergence. For example, two females of the clade III ( WAM T126260 and T126264) from one locality showed substantial differences in the number of rastellum spines (9 vs 17 respectively), which was also notable for four male specimens of the clades II and III (T119726-T119729) from the same location (4 to 10 spines). Similar results were inferred for cuspule count in these males (55 to 80 cuspules on the maxillae).

Figures

Figure 2. Maximum Likelihood phylogeny of all Missulena specimens. The ultimate outgroup taxon Atrax has been removed from the figure for convenience. All bootstrap values below 80 have been removed. Genetic clades within Missulena davidi sp. nov. are colour-coded: clade I brown, clade II red, clade III blue, clade IV pink.

Figure 3. Missulena davidi sp. nov. Male holotype (WAMT 119725): A habitus, dorsal view; B same, ventral view; C carapace, dorsal view; D abdomen, dorsal view; E same, ventral view; F maxillae, labium, and chelicerae, ventral view; G carapace, lateral view. Male paratype (WAMT 119727), left pedipalp, H embolus with embolar tooth, prolateral view; I same, retrolateral view. Scale bars: A, B 4.0 mm; C-G 2.0 mm; H 100 µm; I 40 µm.

Figure 4. Missulena davidi sp. nov. Male holotype (WAMT 119725): A chelicerae with cheliceral groove, ventral view; B patella III, dorsal view; C patella IV, dorsal view; D sternum, ventral view; E eye region, dorsal view; F rastellum, frontal view; G right pedipalp, retrolateral view; H same, ventral view; I same, prolateral view; J pattern of cheliceral teeth in cheliceral groove. Scale bars: A, D-H 2.0 mm; B, C 0.5 mm; J 1.0 mm.

Figure 5. Missulena davidi sp. nov. Female allotype (WAMT 107393): A carapace, dorsal view; B abdomen, dorsal view; C sternum, ventral view; D carapace, lateral view; E maxillae, labium and chelicerae, ventral view; F patella III, dorsal view; G patella IV, dorsal view; H eye region, dorsal view; I rastellum, frontal view. Scale bars: A, B 4.0 mm; C-I 2.0 mm.

Figure 6. Missulena davidi sp. nov. Variability of spermatheca in females: A allotype specimen WAMT 107393, clade I; B specimen WAMT 119995, clade IV; C specimen WAMT 126272, clade II; D specimen WAMT 122226, clade III. Systematic drawings based on allotype WAMT 107393: E spermatheca; F pattern of cheliceral teeth in the cheliceral groove. Scale bars: A-E 0.5 mm; F 2.0 mm

Figure 7. Distribution records of the Missulena davidi sp. nov. in the Pilbara in Western Australia, marked with colour according to clades of the phylogenetic tree (Fig. 2).

Figure 13. Variability in Missulena davidi sp. nov. males: A carapace, dorsal view (T 119729, clade III); B carapace, dorsal view (T 120081, clade II); C carapace, dorsal view (T 119727, clade II); D carapace, dorsal view (T 119733, clade III); E sternum, ventral view (T 113596, clade I); F sternum, ventral view (T 84005, clade I); G abdomen, dorsal view (T 119727, clade II); H abdomen, dorsal view (T 125176, clade III); I eye region, dorsal view (T 120081, clade II); J eye region, dorsal view (T 84005, clade I); K eye region, dorsal view (T 119729, clade III); L rastellum, anterior view (T 84005, clade I); M rastellum, anterior view (T 119726, clade II). Scale bars: A-M 2.0 mm

Figure 14. Variability in Missulena davidi sp. nov. females: A carapace, dorsal view (T 116874, clade IV); B carapace, dorsal view (T 116776, clade I); C carapace, dorsal view (T 113591, clade III); D carapace, dorsal view (T 122226, clade III); E carapace, dorsal view (T 126272, clade II); F sternum, ventral view (T 116776, clade I); G sternum, ventral view (T 119711, clade I); H left maxilla, ventral view (T 119979, clade IV); I right maxillae, ventral view (T 116868, clade I); J eye region, dorsal view (T 116839, clade I); K eye region, dorsal view (T 119979, clade IV); L eye region, dorsal view (T 122865, clade I); M eye region, dorsal view (T 126264, clade III); N rastellum, anterior view (T 125316, clade III); O rastellum, anterior view (T 102165, clade I). Scale bars: A-G 4.0 mm; H-O 2.0 mm.

Figure 15. Missulena davidi sp. nov., male and female variability in carapace length and width in mm; n = 24 females, 12 males.

Figure 16. Missulena davidi sp. nov., male and female variability in PLE and PME width in relation to the ALE width shown in %; n = 25 females, 12 males.