Nukuhiva adamsoni ( Berland, 1933 )

Framenau, Volker W. & Lehtinen, Pekka T., 2015, Nukuhiva Berland, 1935 is a troglobitic wolf spider (Araneae: Lycosidae), not a nursery-web spider (Pisauridae), Zootaxa 4028 (1), pp. 129-135 : 131-133

Nukuhiva adamsoni ( Berland, 1933)

( Figs 1C , 2B )

Dolomedes adamsoni Berland, 1933: 68 –69, figs 55–59.

Nukuhiva adamsoni ( Berland, 1933) .— Berland, 1935: 63, figs 54–56.

Types. Holotype female of Dolomedes adamsoni Berland, 1933 , French Polynesia, Marquesas Islands, Ua Huka, Mt Hitikau, 08°54'20”S, 139°31'17”W, 4 March 1931, LeBronnec, H. Tauraa, 2970ft (BPBM) (designated ‘type’ in Berland (1933)), examined. Paratypes of Dolomedes adamsoni Berland, 1933: 2 females, data as holotype (BPBM) (designated ‘cotypes’ in Berland (1933)), examined. The vial of the type series also contains two immature spiders, which are not mentioned in Berland’s (1933) original description and therefore not considered types.

Other material examined. French Polynesia: Marquesas Islands: 2 juveniles, in type series ( BPBM).

Description. Female (holotype). Carapace. Light brown; indistinct darker radial pattern; ( Figs 1C ); sparse light brown setae, few longer setae in eye region. Eyes. Row of anterior eyes procurved and wider than row of PME. Sternum. Yellowish-brown, some light brown setae mainly along margins in anterior half. Labium. Brown; front end truncated and white. Chelicerae. Reddish-brown; sparse light brown setae basally; three promarginal teeth, the median largest; two retromarginal teeth of similar size. Abdomen. Uniformly light olive-grey without pattern both dorsally and ventrally. Epigyne. Median septum inverted T-shaped ( Fig. 2B ); internal genitalia not examined. Spinnerets light olive-grey. Legs. Uniformly light yellowish-brown; scopulate setae ventrally on tarsi I and II. Spination of leg I: femur: 3 dorsal, 2 apicoprolateral; tibia: 3 ventral pairs, 1 retrolateral; metatarsus: 2 ventral pairs, 1 apicoprolateral, 1 apicoventral.

Measurements. Female holotype: TL 11.00, CL 4.74, CW 3.44. Eyes: AME 0.15, ALE 0.12, PME 0.21, PLE 0.18. Row of eyes: ALE 0.89, PME 0.73, PLE 1.24. Sternum (length/width) 1.88/1.74. Labium (length/width) 0.80/0.80. AL 5.32, AW 3.22. Legs: Lengths of segments (femur + patella + tibia +metatarsus + tarsus = total length): Pedipalp 1.78 + 0.81 + 1.06 + - + 1.52 = 5.17, I 3.35 + 1.85 + 2.67 + 2.35 + 1.44 = 11.66, II 3.20 + 1.62 + 2.38 + 2.48 + 1.34 = 11.02, III 2.65 + 1.22 + 2.36 + 2.60 + 1.66 = 10.49, IV 3.22 + (missing) + (missing) + (missing) = (-).

Variation. The two paratype females have the following measurements: TL 9.33, CL 4.47; CW 3.51; TL 11.05, CL 4.77, CW 3.67. There is no colour variation in these pale spiders.

Male. The male of N. adamsoni was described and illustrated by Berland (1935); however, the specimen on which the description is based could not be located in the BPBM where, according to Berland (1935), they should be housed. We are therefore not able to re-describe the male of this species. Berland’s (1935) description clearly shows a typical ‘hognoid’ pedipalp with a simple sickle-shaped terminal apophysis and triangular tegular apophysis.

Remarks. Berland (1935) listed two further specimens of N. adamsoni from different locations, which could not be located in the BPBM where they are expected to be housed (R. Englund, personal communication to VWF): 1 female, Nuku Hiva, Tapuaooa, 8º54’S, 140º06’W, 1 June 1931, LeBronnec, H. Tauraa, 1000 m; 1 male, Nuku Hiva, summit of island, 8º54’S, 140º06’W, 20 July 1931, LeBronnec, H. Tauraa, 1300 m.

In comparison to other lycosine wolf spiders, e.g. the surface dwelling Hogna crispipes (L. Koch, 1877) ( Fig. 1D ), a common species in the Indo-Pacific region (Framenau et al. 2006), N. adamsoni displays clear characters of troglomorphism, such as reduced eye size and pale colouration ( Fig. 1C ), similar to L. howarthi from Hawai’I ( Fig. 1B ). Therefore, we consider N. adamsoni a troglobitic, or at least troglophile, wolf spider.

Ua Huka, the type locality of N. adamsoni , is a small volcanic island of the Marquesas ( French Polynesia) reaching an altitude of 884 m with cloud forest above 600 m. It is isolated from the nearest island (Nuku Hiva) by 40 km, from the next island group by 600 km and next continent (South America) by 7,300 km (UNEP 2010). Ua Huka and Nuku Hiva were probably once part of a large island ( Legendre et al. 2006) and are composed solely of volcanic rock ( Juberthie 2001). There is minimal knowledge of the subterranean fauna of the Marquesas ( Juberthie 2001), but Mumford (1936) considered that ‘island endemism is developed in the Marquesas to a remarkable degree’.

Volcanic islands, even those much younger than Ua Huka, are renowned for the diversity of their subterranean fauna ( Howarth 1972, 1987). These faunas are typically studied in lava tubes, but also occupy the smaller voids that are typically found in hardened lava flows ( Ashmole & Ashmole 1997). While we could not establish if lava tubes are present on Ua Huka, the frequent volcanism and lava flows will undoubtedly have made available voids suitable for subterranean fauna, such as in the 2.9 Ma old debris avalanche breccias ( Legendre et al. 2006).

Dolomedes noukhaiva Walckenaer, 1847 was described from the Marquesas Islands ( French Polynesia) ( Walckenaer, 1847) and was here considered as potential senior synonym of N. adamsoni . We consider the type material of this species, like other Walckenaer types, lost (e.g. Pickard-Cambridge 1897: 57; Dondale & Redner 1975: 133). The original description of D. noukhaiva suggests it to not to be conspecific with N. adamsoni . It describes the posterior lateral eyes as larger than the posterior median eyes (“ Yeux, les quatre postérieurs plus gros, ceux de la dernière ligne postérieure les plus gros ”), but these are smaller than the posterior median eyes in N. adamsoni . Nukuhiva adamsoni also lacks the annulated legs described for D. noukhaiva (“ verdâtre, avec des anneaux bruns ”). Dolomedes noukhaiva maybe a senior synonym of the prevalent Pacific H. crispipes as it has been found to be abundant in low vegetation on the Marquesas Island, representing the only common mediumsized lycosoid locally (PTL, personal observation).

Figures

FIGURE 1 A – D. Carapace and eye pattern of wolf spiders, dorsal view. A, Adelocosa anops Gertsch, female holotype; B, Lycosa howarthi Gertsch, male holotype; C, Nukuhiva adamsoni Berland, female holotype; D, Hogna crispipes (L. Koch), female from Collie, Western Australia (live).

FIGURE 2 A – C. Male and female genitalia of troglomorphic Pacific wolf spiders. A, Adelocosa anops Gertsch, holotype female, epigyne ventral view; B, Nukuhiva adamsoni Berland, female holotype, epigyne ventral view; C, Lycosa howarthi Gertsch, male holotype, left pedipalp ventral view.