Blakistonia maryae Harrison & Rix & Harvey & Austin 2018, sp. n.
Creators: name: Harrison, Sophie E.
name: Rix, Michael G.
name: Harvey, Mark S.
name: Austin, Andrew D.
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Idiopidae
Blakistonia
Blakistonia maryae

description: Blakistonia maryae, sp. n.
(Fig. 17 A–L)
Type material. AUSTRALIA: South Australia: Holotype male, South Middleback Ranges, 33°14’S, 137°07’E, 6 June 1984, pitfall trap, B. Guerin (SAM NN20077). Paratype: 1 male, South Middleback Ranges, 33°14’S, 137°07’E, 6 June 1984, pitfall trap, B. Guerin (SAM NN20075).
Other material examined. AUSTRALIA: South Australia: 1 female, Scrubby Peak, Gawler Ranges, 33°03’23”S, 136°19’ 40°0”E, 17–26 September 2007, dug up, SEG/DEH Survey 587 (SAM NN26663 DNA); 1 female, Kolay Hut, Gawler Ranges, 32°33’24”S, 135°35’20”E, 11 November 2013, dug up from bank, M. Rix, S.E. Harrison (SAM NN29604 DNA); 1 female, Tumby Bay, Eyre Peninsula, 34°22’27”S, 136°05’18”E, 1 May 2013, dug from grassy verge, S.E. Harrison, M. Harrison (SAM NN29565 DNA); 1 juvenile, same data (NN29566 DNA); 1 male, same data except 5 June 1984 (SAM NN20071); 3 males, Kimba, Eyre Peninsula, 32°29’40.9”S, 135°21’52.0”E, 25–28 November, from pitfall trap, Eyre Peninsula Survey (SAM NN26633–5).
Diagnosis. Males of B. maryae can be distinguished from those of B. bella, B. pidax, B. tunstilli, B. emmottorum, B. gemmelli and B. aurea by the absence of prolateral clasping spurs on tibia I (Fig. 17 G–I); from those of B. plata, B. parva, B. birksi, B. olea, B. tariae, B. carnarvon, and B. raveni by the square eye group (Fig. 17D); and from those of B. newtoni and B. hortoni by the field of spinules on the palpal tibia being relatively narrow and not in a rounded crescent shape (Fig. 17J, L). Females of B. maryae can be distinguished from those of B. wingellina and B. nullarborensis by having a square or slightly subquadrate eye group (Fig. 18D); from those of B. bassi and B. mainae by the combined absence of fine golden hairs on the carapace (Fig. 18A) and the absence of dark brown on the book lungs (in contrast to a paler abdomen) (Fig. 18C); from those of B. birksi by abdominal chevrons being dark golden-brown, with abdomen golden-brown between chevrons (as opposed to chevrons that are dark brown to almost black, with abdomen dark brown between chevrons (Fig. 18A); and from those of B. aurea by the absence of cuspules on the labium (Fig. 18F).
All life stages of B. maryae can also be distinguished from those of other species with sequence data by the following nucleotide substitutions (n = 4 specimens): C(276), G(354); and by the following unique motifs: GAA(482–484).
Description. Holotype male (SAM NN20077). Small idiopid spider (total length 9.4). Colour (in ethanol; Fig. 17 A–C): Carapace, legs and pedipalp pale golden orange-brown, with darker lines on caput, radiating backwards from fovea, and around edges of carapace (Fig. 17A, G–L); sternum, labium and maxillae very similar colour; chelicerae darker red-brown (Fig. 17E, F); abdomen orange golden-brown with pattern of ca. seven mottled, indistinct chevrons, all divided (Fig. 17A, C).
Cephalothorax: Carapace 4.8 long, 3.7 wide, 3.2 high, 1.3 times longer than wide; oval (Fig. 17A), caput low, ocular area raised (Fig. 17C); cuticle smooth, with pits outward from fovea and both sides of caput; fovea straight; carapace very sparsely setose, concentrated and forming fringe around edge of carapace; line of setae between fovea and eye group absent, however, few setae on lateral sides of eye area; median clump of thickened setae on clypeus (Fig. 17D). Length of median clypeus less than 1.0; anterior margin slightly convex. Eye group 0.7 wide, 0.7 long, 0.2 of carapace width; anterior eye row strongly procurved, PLE–PLE /ALE–ALE ratio 1.1; posterior eye row straight to very slightly procurved; AME only slightly smaller than ALE and separated by about the diameter of AME; ALE and PLE separated by about twice the diameter of ALE; PME pale, less than half size of AME and about half size of PLE, and separated from PLE by just less than its own diameter (Fig. 17D). Labium with five cuspules near anterior margin (Fig. 17F). Sternum 2.5 long, 2.1 wide, evenly setose (Fig. 17E). Maxillae with 12 (left) and 21 (right) cuspules (Fig. 17E, F).
Legs: setose and diffusely spinose; tarsi I, II ventrally flattened; metatarsi and distal tarsi I, II weakly scopulate (Fig. 17 G–I). Paired tarsal claws: leg I p6 (6 large) r6 (6 large); leg II p8 (3 large, 5 small), r8 (3 large, 5 small); leg III p7 (3 large, 4 small), r5 (3 large, 2 small); leg IV p9 (9 large), r7 (3 large, 4 small).
Spination: Tibia I with single prolateral macroseta (Fig. 17 G–I). All legs without clear demarcation between lanceolate setae and smaller spine-like setae.
Leg and pedipalp measurements: Length of legs IV> I> II> III. Leg I: femur 4.5, patella 2.1, tibia 3.4, metatarsus 3.1, tarsus 1.6, total = 15.3. Leg II: femur 4.4, patella 2.0, tibia 3.3, metatarsus 2.2, tarsus 2.1, total = 14.0. Leg III: femur 3.1, patella 1.6, tibia 2.6, metatarsus 3.2, tarsus 2.3, total = 12.3. Leg IV (right): femur 4.7, patella 2.6, tibia 4.5, metatarsus 4.5, tarsus 2.6, total = 18.4. Pedipalp: femur 2.5, patella 1.2, tibia 2.2, tarsus 1.2, total = 7.2.
Pedipalp: Femur dorsally spinose; patella with thickened ventral setae; tibia short and swollen, RTA very short, pointed, with clump of setae and covered in short, dense spinules and for just over half of distance between base of apophysis and distal tibia, becoming more sparse towards distal tibia; long, erect setae on ventral tibia; bulb uniform, globular; embolus simple, slender, tapering, tip slightly twisted, only slightly longer than bulb; cymbium covered in rows of short spinules, becoming longer closer to distal edge (Fig. 17 J–L).
Abdomen: Setose, oval, dorsal sigilla not evident; 4.6 long, 2.7 wide (Fig. 17A).
Variation (n=6): Carapace 3.0–4.8 long, 2.5–2.7 wide, 5-6 labial cuspules.
Female (SAM NN29565). Medium-sized idiopid spider (total length 18.5).
Colour (in ethanol; Fig. 18 A–C): Carapace medium golden-brown, slightly darker around fovea and lateral margins of caput; sternum lighter golden-brown, darker towards anterior and lateral margins; labium and maxillae same golden-brown as margins of sternum, chelicerae dark brown (Fig. 18E, F); abdomen grey-brown with 6 mottled chevrons of uniform width spaced over length of abdomen, anterior-most chevron divided by pale medial patch (Fig. 18A, C); legs and pedipalps medium golden-brown (Fig. 18G, H).
Cephalothorax: Carapace 8.2 long, 6.3 wide, 5.9 high, 1.3 times longer than wide; oval (Fig. 18A); caput moderately raised, ocular area very slightly raised (Fig. 18C); cuticle uniformly smooth; fovea procurved; two parallel rows of large setae from fovea to eye group, with smaller setae located laterally to these rows; smaller fine setae also scattered across carapace, concentrated and forming fringe around lateral margins; median clump of thickened setae on clypeus (Fig. 18D). Length of median clypeus less than 1.0; anterior margin slightly convex. Eye group 1.4 wide, 0.9 long, 0.2 of carapace width; anterior eye row strongly procurved, PLE–PLE/ALE–ALE ratio 1.0; posterior eye row straight; AME ca. two-thirds the size of ALE and separated by less than diameter of AME; ALE and PLE separated by about diameter of AME; PLE and PME contiguous, oval (Fig. 18D). Labium without cuspules (Fig. 18F). Sternum 4.3 long, 3.5 wide, moderately setose with setae becoming denser and longer around margins; 3 pairs of sigilla, anterior-most pair at lateral margins, middle pair at half length, posterior pair slightly less than twice their width from edge (Fig. 18E). Maxillae with 22 (left) and 32 (right) cuspules (Fig. 18E, F).
Legs: moderately setose and diffusely spinose, leg III more heavily setose; distinct upright setae on metatarsi and of tibiae I, II; femora I, II, and pedipalp laterally bowed; tarsi and metatarsi I, II, and palpal tarsus heavily scopulate (Fig. 18G, H). Paired tarsal claws: p1 (1 large) r2 (2 large); leg II p3 (2 large, 1 small), r1 (large); right leg III r2 (1 large, 1 small), r2 (2 small); right leg IV p0, r4 (1 large, 4 small). Pedipalp claw with 2 large teeth.
Spination: Leg I: tibia p1, r5; metatarsus p4, r7; tarsus p3, r8. Leg II: tibia p4, r5; metatarsus II p4, r5; tarsus II p2, r4. Right leg III: patella p7; metatarsus III p6, r10; tarsus with 11 short spines ventrally. Right leg tibia IV: p8, r3; tarsus with ca. 23 short spines ventrally. Pedipalp: tibia p8, r5; tarsus p3, r3.
Leg and pedipalp measurements: Length of legs IV> II> I> III. Leg I: femur 3.7, patella 2.7, tibia 2.4, metatarsus 2.0, tarsus 1.7, total = 12.5. Leg II: femur 4.2, patella 2.9, tibia 2.7, metatarsus 2.0, tarsus 1.8, total = 13.6. Leg III (right): femur 3.4, patella 2.5, tibia 2.1, metatarsus 1.5, tarsus 1.5, total = 11.8. Leg IV (right): femur 5.2, patella 3.7, tibia 4.6, metatarsus 3.8, tarsus 4.1, total = 21.4. Pedipalp: femur 3.6, patella 2.3, tibia 2.2, tarsus 2.8, total = 10.9.
Abdomen: Setose, oval, three pairs of non-sclerotised, irregular dorsal sigilla on anterior three chevrons; 10.3 long, 6.8 wide (Fig. 18A).
Genitalia: Spermathecae paired, simple, unbranched, stout and outward facing, with lobe of epigyne ca. same width as stalk, covered in opaque mottled brown nodules, becoming more concentrated towards distal spermathecae (Fig. 18I).
Variation (n=3): Carapace 6.7–10.3 long, 6.2–7.7 wide, no labial cuspules. Spination: Leg I: tibia p1–3, r4–6; metatarsus r3–4, r5–7; tarsus p2–3, r3–8. Leg II: tibia p1–4, r5–7: metatarsus p4 r5–7; tarsus p2–3, tarsus r4–11. Leg III: patella p5–7, tibia p0–2, r0–1; tarsus with 11–17 short spines ventrally. Leg IV: tibia p0–1, r0–1; metatarsus p6–11, r2–4; tarsus with 20–28 spines ventrally. Pedipalp: tibia p2–9, r4–7; tarsus p3–5, r3–4.
Etymology. This species is named in honour of the senior author’s mother, Mary Harrison, for her invaluable assistance on numerous collecting trips.
Distribution. Blakistonia maryae is found on the Eyre Peninsula, and is known from Tumby Bay, the Middleback Ranges, Kimba, and two localities in the Gawler Ranges (Fig. 32).
Remarks. The burrow lid of B. maryae is D-shaped and slightly indented (Fig. 2 H–K). The rim of the burrow is usually lined with twigs and small leaves (Fig. 2 H–K), which although common in other idiopid genera such as Idiosoma and Gaius, has not been previously documented in Blakistonia. These twigs are used as ‘feeling lines’ to increase the area of foraging (Main 1962). Twig-lining was not observed in the specimen from Kolay Hut, Gawler Ranges (Fig. 2K), however, it is likely that the absence of twig-lining was a result of the burrow being built on an unconsolidated bank, with erosion and no leaf litter available. We have tentatively linked the females from Tumby Bay and Gawler Ranges with the males from Kimba and Mount Crawford, due to their distributions on the Eyre Peninsula, and no conflicting differences in other morphological features, such as eye group shape.
description: Published as part of Harrison, Sophie E., Rix, Michael G., Harvey, Mark S. & Austin, Andrew D., 2018, Systematics of the Australian spiny trapdoor spiders of the genus Blakistonia Hogg (Araneae: Idiopidae), pp. 1-76 in Zootaxa 4518 (1) on pages 45-49, DOI: 10.11646/zootaxa.4518.1.1, http://zenodo.org/record/2609500