Cavisternum digweedi, Baehr & Harvey & Smith, 2010

Baehr, Barbara C., Harvey, Mark S. & Smith, Helen M., 2010, The Goblin Spiders of the New Endemic Australian Genus Cavisternum (Araneae: Oonopidae), American Museum Novitates 3684, pp. 1-40 : 21-22

Cavisternum digweedi , new species

Figures 14 , 98–102 , map 1

TYPES: AUSTRALIA: Northern Territory: Male holotype from Kakadu National Park, Kapalga , site B2, 12 ° 23 9 S, 132 ° 18 9 E (5 Oct. 1986, A. Andersen et al.) (PBI_OON 00005438), deposited in WAM (T78180). Female allotype from Kakadu National Park , Kalpalga, site A1, 12 ° 29 9 S, 132 ° 19 9 E, woodland, pitfalls (15 Sep. 1986, A. Andersen)

(PBI_OON 00004609), deposited in WAM (T82247). Paratypes: 1 female from Kakadu National Park , Kapalga, site B2, 12 ° 23 9 S, 132 ° 18 9 E (26 Nov. 1986, A. Andersen (PBI_OON 00003997), deposited in WAM (T82253) ; 1 female from Kakadu National Park , site B1, 12 ° 23 9 S, 132 ° 18 9 E, open forest, pitfalls (17 Dec. 1986, A. Andersen) (PBI_OON 00003995), deposited in WAM (T82252) ; 1 female from Kakadu National Park , site A2, 12 ° 29 9 S, 132 ° 19 9 E, woodland (30 June–2 July 1986, A. Andersen) (PBI_OON 00003992) deposited in WAM (T82250) ; 1 female from Kakadu National Park , Kalpaga, site A1, 12 ° 29 9 S, 132 ° 19 9 E, woodland, pitfalls (1 Oct. 1986, A. Andersen) (PBI_OON 00003991), deposited in WAM (T82249) ; 1 female from Kakadu National Park , site B1, 12 ° 23 9 S, 132 ° 18 9 E, open forest, pitfalls (7 Apr. 1987, A. Andersen) (PBI_OON 00003994) (WAM T82251) ; 2 males from Annaburroo , 12 ° 50 9 S, 131 ° 49 9 E (Oct. 1997, T.B. Churchill) (PBI_OON 00005432, PBI_OON 00005433), deposited in WAM (T82254, T82255) .

ETYMOLOGY: The specific name is a patronym in honor of young Kai Digweed, born April 2009. Kai’s arachnophobe father is determined that his son should grow up to respect but not fear spiders.

DIAGNOSIS: Males of C. digweedi resemble those of C. bertmaini , with the sternal concavity occupying about half of the sternal length (fig. 14), and the epigastric scutum strongly protruding. Males of C. digweedi can be easily separated by their ovoid cymbium-bulb complex with a broadly based embolus and a twisted bifurcate tip (figs. 98– 100). Females can be easily distinguished from all other Cavisternum species by the broad semicircular epigynal rim as wide as the apodemes, and the extremely narrow copulatory duct (figs. 101, 102).

MALE: Total length 1.07. Carapace 0.52 long, 0.37 wide; abdomen 0.55 long, 0.29 wide. Carapace, sternum, mouthparts, and abdominal scutae pale orange, legs yellow. Sternum as long as wide, concavity small with dropshaped field of clavate setae, covering about M of sternum width and K of sternum length, in posterior median part of sternum (fig. 14). Cheliceral fangs elongated, tips bent posteromedially, positioned in V shape, tip distally widened. Abdomen ovoid, epigastric scutum strongly protruding. Cymbium-bulb complex ovoid with a broadly based embolus and a twisted bifurcate tip (figs. 98–100).

FEMALE: Total length 1.25. Carapace 0.49 long, 0.37 wide; abdomen 0.76 long, 0.31 wide. Coloration as in male. Epigastric area with dark semicircular rim, reaching apodemes laterally, with extremely narrow copulatory duct (figs. 101, 102).

DISTRIBUTION: This species is found in the north of the Northern Territory (map 1).

Figures

Figs. 10–17. Cavisternum species, males, sterna and chelicerae, ventral view. 10. C. bagleyae (PBI_OON 06235). 11. C. barthorum (PBI_OON 06073). 12. C. bertmaini (PBI_OON 05440). 13. C. carae (PBI_OON 05434). 14. C. digweedi (PBI_OON 05438). 15. C. foxae (PBI_OON 06069). 16. C. gatangel (PBI_OON 06070). 17. C. heywoodi (PBI_OON 07474).

Figs. 98–102. Cavisternum digweedi, new species. 98–100. Male palp (PBI_OON 05438). 98. Prolateral view. 99. Retrolateral view. 100. Dorsal view. 101, 102. Female epigyne (PBI_OON 04609). 101. Ventral view; broad epigynal rim indicated. 102. Dorsal view.