Missulena langlandsi

Description. Adult male, based on holotype WAM T 115948. Small spider (total length 4.9). Colour: carapace base colour black, caput and chelicerae uniformly orange-red (Figs 8 A – D); eye region orange-red but ALE, AME and PLE on black tubercles (Fig. 8 B); chelicerae with black setae, fangs orange-brown; abdomen greyish-brown with black setae, distal portion with light brown transverse lines which are diagonally oblique (Figs 8 A, 10 G); sternum distally olive-green but proximally orange, margins contoured greyish-orange (Fig. 9 A), sigilla orange-brown, many grey setae; labium uniformly orange, maxillae olive-green but heel orange (Fig. 9 B); legs black or dark grey, articles greyish-white (Fig. 8 A); spinnerets greyish-brown, spigots brown (Fig. 9 C). Carapace: 2.4 long, 2.9 wide; caput and eye region elevated in lateral view, strongly arched and differentiated from lower carapace (Fig. 8 C); fovea deep, strongly procurved (Fig. 8 D); lower carapace rugose with bands of fine, random fissures centered around fovea (Fig. 8 B). Eyes: OQ 4.3 times wider than long, occupies 0.72 of cephalic width; MOQ 1.15 long; width of anterior eye group 1.9, width of posterior group 1.7, OQ length 0.43; AME on tubercle, 0.4 wide, 0.25 long; AME interdistance 0.08; AME to ALE 0.35; PLE to ALE 0.25; PME to ALE 0.25; PLE to PME 0.2; eye region with black setae, one straight line of ca. 10 setae between AME and fovea; two other oblique lines of 10 setae between fovea and lateral eyes (Fig. 10 D). Chelicerae: 1.7 long, 1.0 wide; distally broad and diagonal, slightly conical; edges smoothly rounded; outer surface smooth and without ridges (Fig. 10 E); proximal parts without setae, distal and interior parts with ca. 70 setae, these setae distally increase in size (Figs 10 A – C); rastellum not very pronounced, a shallow process with 7 − 10 basally thickened black setae interspersed with 9 − 12 longer and thinner setae, thick setae ca. 1 / 3 shorter and thicker than others; 10 − 12 long setae extend forward from anterior margin of each chelicera and cover base of fang, setae largest on latero-ventral side; inner margin of cheliceral furrow with two rows of teeth, prolateral (inner) row consists of 7 spaced, conical teeth, retrolateral (outer) row with two proximal, spaced teeth; basomedial tooth present (Figs 10 E, F). Maxillae: 1.3 long; 0.8 wide; almost square, 22 – 25 small cuspules along entire anterior margin but distally sparser (Fig. 9 E). Labium: 0.7 long, 0.6 wide; conical, ca. 8 – 10 small cuspules distally (Fig. 9 D); labiosternal suture as shallow groove (Fig. 9 B); pair of sigilla near labiosternal suture, kidney-shaped and well-defined. Sternum: 1.7 long; 1.6 wide; oval, rebordered; many long setae present, three pairs of sigilla, anterior two pairs smaller than most posterior pair, all well defined, depressed and roughly oval (Fig. 9 A). Abdomen: 2.4 long, 2.8 wide; roughly oval without bumps or processes (Fig. 10 G); four spinnerets, PLS 0.9 long, 0.4 wide, apical segment domed (Fig. 9 C); PMS 0.40 long, 0.2 wide. Pedipalp: length of trochanter 0.4, femur 2.2, patella 1.1, tibia 2.2, tarsus 0.9; entire palp aspinose, tarsus terminally blunt (Figs 11 D, E); bulb pyriform (Figs 11 A, B, D, E), two strongly sclerotised sections connected by median haematodocha (Fig. 12 F), bulb slightly twisted proventrally; embolus medium-sized, tapering and slightly bent medially, directed upwards (Figs 12 D, E, F); embolus tip simple, without processes (Fig. 11 C). Legs: covered uniformly with more than 250 long and thin black setae; setae of tibiae, metatarsi and tarsi as long or longer than diameter of respective segment; preening comb absent; legs I – II ascopulate, metatarsi III scopulate ventrally across distal half, metatarsi IV and tarsi III – IV ventrally scopulate across entire length. Leg spination: pedipalp aspinose; leg I: tibia rv 0, v 13, pv 0, d 0; pv 0, d 0; tarsus rv 0, v 4, pv 0, d 0; leg II: tibia rv 0, v 13, pv 0, d 0; metatarsus rv 0, v 6, pv 0, d 0; tarsus rv 0, v 5, pv 2, d 0; leg III: tibia rv 5, v 13, pv 3 (apical), d 0; metatarsus rv 5, v 6, pv 3, d 6; tarsus rv 1, v 9, pv 4, d 2 (apical); leg IV: tibia rv 2 (apical), v 6, pv 0, d 0; metatarsus rv 8, v 11, pv 0, d 1 (apical); tarsus rv 9, v 19, pv 0, d 2 (apical); patellae I with two apical spines (Figs 8 E, F); patellae II with three apical spines dorsally; patellae III with 22 rasps in five discontinuous rows dorsally (Fig. 8 G); patellae IV with five irregular spines dorsally (Fig. 8 H). Leg measurements: leg formula IV> I> II> III. Leg I: coxa 1.2, trochanter 0.7, femur 2.5, patella 1.25, tibia 1.6, metatarsus 2.0, tarsus 1.1, total = 10.35; tibia width 0.5, leg I index = 4.3. Leg II: coxa 1.2, trochanter 0.7, femur 2.3, patella 1.25, tibia 1.85, metatarsus 1.8, tarsus 1.2, total = 10.3, tibia width 0.6, leg II index = 4.3; Leg III: coxa 1.2, trochanter 0.7, femur 2.3, patella 1.1, tibia 1.4, metatarsus 1.7, tarsus 1.2, total = 9.6; tibia width 0.7, leg III index = 4.0. Leg IV: coxa 1.2, trochanter 0.6, femur 3.4, patella 1.3, tibia 1.8, metatarsus 1.9, tarsus 1.2, total = 11.4; tibia width 0.65, leg IV index = 4.75. Trichobothria: arranged in discontinuous rows; tibiae I – IV with two rows of 3 in dorsolateral position, first row prodorsal and second row retrodorsal; metatarsi with 4 mediodorsal, tarsi I – II with 3 and tarsi III – IV with 4 mediodorsal. Tarsal claws: leg I: 5 − 8 / 3; leg II: 4 − 5 / 2; leg III: 4 − 5 / 1; leg IV: 0 − 1 / 1, all teeth prominent and clearly divided; claws about as long as spines of tarsi. Variation in paratypes (N = 5): total length 4.6 – 5.2, carapace 2.4 – 2.8 long, 2.9 – 3.1 wide; cephalic region may be slightly granulate; prolateral row of cheliceral teeth consists of 4 – 7 teeth; one or two more teeth may be present basally in fang groove between the two rows of teeth; labial cuspules may be absent or reduced to a few tiny grey spots, maxillary cuspules may be small and present as 15 − 30 tiny grey spots. The spination of the rastellum varies considerably. One paratype (WAM T 112076) has three thick spines in addition to the basally thickened setae on the right, but not the left chelicera. A third specimen (WAM T 91911) has three to four thick spines on a prominent elevation but no basally thickened setae. The character is variable between and even within specimens and care must be taken in using it for the identification of this species. The rastellum is slightly more elevated and the number of basally thickened setae is lower in specimens with prominent spines whereas specimens without spines have generally more thickened setae on a very shallow elevation.

Diagnosis. Males of M. langlandsi sp. nov. differ from other red-headed Missulena (M. occatoria, M. insignis and M. reflexa) in their small body size (about <5.0 in M. langlandsi,> 8.0 in other species), small number of cheliceral teeth (retrolateral row with less than 7 teeth), rastellum with less than 8 spines, patellae III with less than 30 rasps, patellae IV with less than 15 rasps, and the undivided second pair of sigilla (see Womersley 1943: 262). Females of M. langlandsi sp. nov. are unknown.

Distribution. Missulena langlandsi sp. nov. is currently only known from the floodplain of Weeli Wolli Creek north-west of Newman (Fig. 2 B). Phenology and habitat preferences. Males of M. langlandsi sp. nov. were collected from May to June when annual average temperatures in the Pilbara are at their lowest and rainfall decreases. The holotype of M. langlandsi sp. nov. was collected adjacent to the then dry creek bed of Weeli Wolli Creek in open habitat dominated by spinifex (Triodia spp.) and introduced Buffel grass (Cenchrus ciliaris) with scattered gum trees (Eucalyptus spp. / Carymbia spp.) (Fig. 1 B). It was collected during the day, wandering around in bright sunshine.

Etymology. The specific epithet is a patronym in honour of Peter Langlands, the collector of the holotype, for his keen interest in natural history and nature conservation.

Type material. AUSTRALIA: Western Australia: holotype male, Wonmunna mining lease, ca. 73 km heading 291 ° from Newman, 23 ° 07 ’ 16 ” S, 119 ° 03 ’ 48 ” E, 20 May 2011, hand-collecting, P. R. Langlands (WAM T 115948). Paratypes: 1 male, same data as holotype except 23 ° 07 ’ 09 ” S, 119 ° 03 ’ 52 ” E, 20 May – 22 June 2011, wet pitfall trap (WAM T 112076 DNA) Other material examined. AUSTRALIA: Western Australia: 1 male, Hamersley Range, Weeli Wolli Creek region, 22 ° 55 ’ 54 ” S, 119 ° 02 ’ 50 ” E, 17 June 2008, P. Bolton & J. Puglisi (WAM T 91914 DNA); 1 male, same data except 22 ° 55 ’ 53 ” S, 119 ° 02 ’ 49 ” E (WAM T 91912); 1 male, same data except 22 ° 55 ’ 53 ” S, 119 ° 02 ’ 50 ” E (WAM T 91913); 1 male, same data except 22 ° 55 ’ 33 ” S, 119 ° 02 ’ 16 ” E, 15 June 2008 (WAM T 91911 DNA).