Tuesday, October 3, 2017

[Arachnida • 2017] Ocyale ghost • A New Species of Ocyale (Araneae, Lycosidae) from Madagascar, with First Observations on the Biology of A Representative in the Genus

Ocyale ghost Jocque & Jocqué, 2017

in Jocque, Wellens, Andrianarivosoa, Rakotondraparany, Seing & Jocqué, 2017


large white species of wolf spider, Ocyale ghost Jocque M. & Jocqué R. sp. nov., is described from a white sandy beach of an inland freshwater lake in the northwest of Madagascar. The first photos of a living specimen of the genus Ocyale are provided together with some observations on the biology of the newly described species. An updated and illustrated key to the Afrotropical species of Ocyale is included here.

Keywords:  beach; biology; phenology; white sand

Class Arachnida Cuvier, 1812
Order Araneae Clerck, 1757
Family Lycosidae Sundevall, 1833

Ocyale Audouin, 1823 

 Species included:
O. dewinterae Alderweireldt, 1996 ♂♀
O. discrepans Roewer, 1960 ♀
O. ghost Jocque M. & Jocqué R. sp. nov. ♂♀
O. grandis Alderweireldt, 1996 ♂♀
O. guttata Karsch, 1878 ♂♀
O. pilosa Roewer, 1960 ♂♀

Fig. 3. Ocyale ghost Jocque M. & Jocqué R. sp. nov. photographed at type locality.
A. Female habitus. B. Same, detail. C. Female in sand retreat. D. Female with spiderlings on abdomen. E. Two males, one being eaten by the other. F. Female with white grasshopper prey.

 Photos A–B: MJ (2012), C–F: SW (2016).

Ocyale ghost Jocque M. & Jocqué R. sp. nov.

Diagnosis: Males of Ocyale ghost sp. nov. can be recognized by details of the male palp: the tegulum is restricted to the prolateral side of the bulbus, the distal prong of the palea appendage is much narrower than the proximal one and the MA with the perpendicular prong is rectangular. Females are characterized by the epigyne in which the T-shaped posterior sclerite is fully exposed and not covered with setae as in other species in the genus. 

Etymology: The species name ‘ghost’ refers to the fully white appearance of this spider. Additional reference is made to the large white direwolf ‘Ghost’ in Game of Thrones, the first book in the series of fantasy novels A Song of Ice and Fire by George R.R. Martin.  

Biology: Ocyale ghost sp. nov. was only found on the white sandy beaches (Fig. 3A–B) of an inland lake in the study region. The surveys also included grassland and dry forest, but the species seems restricted to a white-sand habitat, as reflected in its habitus. Ocyale ghost sp. nov. is active at night and all specimens were caught with headlamps after sunset. Captured animals that were kept alive in large ziplock bags overnight constructed retreats in the sand, lined with silk (Fig. 3C). Possible prey include large insects such as grasshoppers (Fig. 3F) that also exhibit camouflage colours as an adaptation to the white beach they live on. Intraspecific predation is also likely to occur (Fig. 3E), a phenomenon which is not unusual among lycosids (Edgar 1969; Hallander 1970). We observed copulation and females with spiderlings (Fig. 3D) in the midst of the dry season (June–July). Juveniles of a complete range of size, from very small ones (6 mm TL) to subadults, were observed, indicating that this species might reproduce yearround. The permanent presence of water in its habitat might explain why this species is also active in the dry season when spider activity is on average very low.

Fig. 2. Habitat on type locality of Ocyale ghost Jocque M. & Jocqué R. sp. nov. (photo by MJ, July 2012).

Merlijn Jocque, Siel Wellens, J.D. Andrianarivosoa, F. Rakotondraparany, Sam The Seing and Rudy Jocqué. 2017. A New Species of Ocyale (Araneae, Lycosidae) from Madagascar, with First Observations on the Biology of A Representative in the Genus. European Journal of Taxonomy. 355; 1–13.  DOI:  10.5852/ejt.2017.355


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