Labahitha fuscata ( Nakatsudi, 1943 ), 2022

Magalhaes, Ivan L. F., Berry, James W., Koh, Joseph K. H. & Gray, Michael R., 2022, Labahitha spiders (Arachnida: Araneae: Filistatidae) from islands in the Indian and Pacific Oceans, European Journal of Taxonomy 805 (1), pp. 1-51 : 6-12

Labahitha fuscata ( Nakatsudi, 1943) comb. nov.

Figs 2A–B , 4–6 , 29C

Filistata fuscata Nakatsudi, 1943: 148 , fig. 1a–c. Female holotype from Palau, Koror Island, Aug.1941, T. Ogata leg., presumably deposited in the Tokyo University of Agriculture ( Ono 2011), not examined.

Filistata fuscata Kishida, 1947: 999 , fig. 2839. Syntypes from Japanese Micronesia, currently untraceable ( Ono 2011), not examined. First considered a junior synonym and homonym of Filistata fuscata Nakatsudi, 1943 by Ono (2011).

Nr. Wandella sp. – Gray 1995: 84, figs 15, 19.

Tricalamus fuscatus – Ono 2011: 185, figs 1–11; 2013: 19.

Notes

Although neither Ono (2011) nor we have examined the type specimens, we have seen plenty of specimens from the type locality and neighbouring islands that tally with the original descriptions of this species. Ono (2013) recorded this species in the Ogasawara Islands in Japan. Gray (1995: fig. 15) was the first to figure the male of this species. See Ono (2011) for a discussion regarding the correct authorship of this species and the priority of Nakatsudi’s (1943) name over Kishida’s (1947).

Diagnosis

The male is similar to that of Labahitha gibsonhilli in the sharp, triangular apex of the paraembolic lamina and the gently curved distal portion of the sperm duct. It differs by the shorter, more stout palpal bulb and the relatively larger paraembolic lamina ( Fig. 5B, J–L ) (vs palpal bulb longer and slender, with smaller paraembolic lamina in L. gibsonhilli ). Females can be distinguished from all congeners by the very small median receptacles, which are reduced to a bump with pores, placed posteriorly to the larger, oval lateral receptacles ( Fig. 6 ). The deep brown and uniform colouration is also characteristic ( Fig. 4 ), although also present in L. ryukyuensis ( Ono 2013) .

Material examined

AUSTRALIA • 1 ♂; Queensland, Torres Strait, Darnley Island ; [9.59747° S, 143.76142° E]; AM .

BRUNEI • 1 ♀; Tutong, Tasek Merimbun Park HQ ; [4.59444° N, 114.67083° E]; 13 Feb. 2013; J.K.H. Koh leg.; wooden wall crevices; JK 130213.1101 • 1 ♀; same collection data as for preceding; 16 Apr. 2011; JK 110416.1907 .

FIJI • 1 ♀; Vanua Levu , Lasema ; [16.62682° S, 179.01793° E]; W.M. Mann leg.; MCZ 40200 .

MARSHALL ISLANDS • 1 ♀; Kwajalein Atoll, Ennugarret Island ; [9.38452° N, 167.4881° E]; 9 Jul. 1968; J.W. Berry leg.; beating trees in Pandanus forest; JBJB • 1 ♂; Majuro Atoll, Woja ; [7.09171° N, 171.38268° E]; 26 Jul. 1968; J.W. Berry leg.; in coconut litter; JBJB .

MICRONESIA • 1 ♀; Caroline Islands , “ Truk Islands ” [ Chuuk Island ], “ Moen Island ” [ Weno Island ]; [7.45575° N, 151.84985° E]; 12 Jun. 1978; J. Berry and Beatty leg.; in crevices on buildings; JBJB • 1 ♀; Caroline Islands, Yap Island , Yap District, Fedor ; [9.45056° N, 138.06269° E]; 1 Feb. 1980; J.W. Berry leg.; in banana leaves; JBJB • 1 ♀; Caroline Islands, Yap Island , Yap District, Fedor ; [9.45056° N, 138.06269° E]; 13 Apr. 1980; J.A. Beatty leg.; in web on tree trunk; JBJB • 1 ♂, 1 ♀; Caroline Islands, Yap Island , Yap, near Gilman Point; [9.45056° N, 138.06269° E]; 15 Apr. 1980; webs in crevices on mango tree bark; JBJB .

NEW CALEDONIA • 2 ♀♀, 1 imm.; Nord , Poum; [20.23333° S, 164.01667° E]; 13 Feb. 1993; N.I. Platnick, R.J. Raven and M.S. Harvey leg.; coastal cliffs; AMNH IFM-0917 , IFM-0918 .

PALAU • 1 ♂; Caroline Islands, Koror Island ; [7.34068° N, 134.4792° E]; 17 Mar. 1973; J. Berry and Beatty leg.; in cave entrance rock cracks; JBJB • 1 ♀; same collection data as for preceding; JBJB • 1 ♀; Caroline Islands, Koror Island ; [7.34068° N, 134.4792° E]; 17 Mar. 1973; J. Berry and J. Beatty leg.; in crevices of tree trunk bark; JBJB • 1 ♂, 1 ♀; Caroline Islands, Koror Island , on Entomology Lab building ; [7.34068° N, 134.4792° E]; 7 Mar. 1973; J.A. Beatty leg.; JBJB • 1 ♀; same collection data as for preceding; 6 Mar. 1973; J. Berry and J. Beatty leg.; JBJB .

PAPUA NEW GUINEA • 2 ♀♀; Bismarck Islands ; [5.55234° S, 150.13883° E]; 18 Nov. 1896; ZMB .

Description

Male (from Palau, Koror Island, Entomology Laboratory, JBJB)

COLOURATION (in ethanol). Carapace grey-brown, with darker irregular patterning in the median postocular area and the weakly defined mid-lateral and lateral marginal bands. Chelicerae, labium, endites and sternum brown. Legs with dark grey-brown pigmentation on femora, paler on tibiae and reduced to absent on remaining segments. Abdomen colour brownish grey with and several indistinct chevrons, but patterning poorly preserved.

HABITUS. Anterior margin of carapace subrounded, sclerotized but apical part with an unsclerotized curved edge. Sternum subrounded, posteriorly bluntly pointed, a pair of posterior sigilla present.

MEASUREMENTS. Total length 3.23. Carapace length 1.37, width 1.13. Clypeus length 0.33. Eye diameters and interdistances: AME 0.05, PME 0.08, ALE 0.09, PLE 0.09, AME–AME 0.05, PME–PME 0.09. Sternum length 0.95, width 0.71. Palp: femur length 0.77, height 0.23; tibia length 0.49, height 0.22. Legs 1423. Leg I: 6.33 (1.63, 0.49, 1.80, 1.42, 0.99). II: 4.63 (1.24, 0.43, 1.14, 1.18, 0.64). III: 4.26 (1.10, 0.39, 0.95, 1.07, 0.75). IV: 5.41 (1.41, 0.49, 1.43, 1.44, 0.64). Abdomen length 1.86, width 0.86.

LEG MACROSETAE. Metatarsus (Mt) I 1 a.vr.

PALP ( Fig. 5 ). Cymbium horseshoe shaped; bulb enlarged with a median constriction, sperm duct Nshaped with a single coil; tegulum with a large prolateral excavation, its surface adorned with strongly spined short ridges (each typically bispinate); large crest-like paraembolic process with a fimbriated dorsal margin bent more or less prolaterally, and narrowing distally to end in an extension above the embolus; comb-like microtooth arrays present on paraembolic process; embolus slender, slightly curved.

Female (from Palau, Koror Island, Entomology Laboratory, JBJB)

COLOURATION. Carapace similar to male, but anterior margin of carapace pigmented. Abdomen greyish brown with a longitudinal pale patch mid-dorsally and several indistinct pale chevrons laterally. One pair of posterior sternal sigilla present.

MEASUREMENTS. Total length 4.75. Carapace length 1.69, width 1.33. Clypeus length 0.29. Sternum length 0.95, width 0.71. Palp: femur length 0.91, height 0.3; tibia length 0.42, height 0.3. Leg I: 5.71 (1.45, 0.52, 1.49, 1.32, 0.93). II: 4.22 (1.16, 0.49, 0.95, 0.95, 0.67). III: 3.7 (1.05, 0.48, 0.78, 0.85, 0.54). IV: 4.92 (1.41, 0.60, 1.25, 1.05, 0.61). Abdomen length 3.06, width 2.07.

LEG MACROSETAE. Absent. Calamistrum with three rows.

EPIGASTRIC FURROW. Unmodified.

ENDOGYNE ( Fig. 6 ). Median lobes very small with a few clustered pores; lateral lobes large, ovoid in side view, with scattered pores.

Variation

Male genitalia is similar across islands ( Fig. 5 ). The shape of the lateral receptacles varies from rounded to oval, and the pores in the lateral receptacles may be concentrated in the ectal side or dispersed throughout the receptacle ( Fig. 6 ).

Natural history

Specimens have been collected in habitats as diverse as wooden wall crevices, in coconut litter, in crevices on buildings, by beating trees in Pandanus forest, in banana leaves, in web on tree trunk, in webs in crevices on tree bark, in coastal cliffs and in cave entrance rock cracks.

Distribution

Widespread in Micronesia and Melanesia, extending into Borneo and Japan ( Fig. 1 ).

Figures

Fig. 2. Labahitha Zonstein, Marusik & Magalhaes, 2017, live specimens. A–B. Labahitha fuscata (Nakatsudi, 1943) comb.nov., from Brunei, Tutong.A. Female.B. Female with juveniles.C–E. Labahitha garciai (Simon, 1892) comb. nov., from Singapore. C. Male. D. Female (arrow) in her web. E. Female. Photos by Joseph Koh, except D by Chris Ang.

Fig. 4. Labahitha fuscata (Nakatsudi, 1943) comb. nov., females. A. Brunei, Tutong, habitus, dorsal (JK 130213.1101). B. Papua New Guinea, Bismarck Islands, habitus, dorsal (ZMB). C–G. New Caledonia, Poum (AMNH IFM-0917). C. Habitus, dorsal. D. Habitus, ventral. E. Habitus, lateral. F. Genital region, ventral. G. Spinnerets, ventral. H–J. Female from the same locality (AMNH IFM- 0918). H. Sternum, ventral. I. Carapace, dorsal. J. Left calamistrum, retrolateral. Scale bars = 1 mm, except where noted.

Fig. 5. Labahitha fuscata (Nakatsudi, 1943) comb. nov., males. A–I. Palau, Koror (JBJB), left palp. A. Retrolateral. B. Prolateral. C. Dorsal. D. Prolateral, detail. E. Tarsal organ. F. Trichobothria base. G. Detail of tegular spines. H. Detail of arrays of micro-teeth combs. I. Semi-plumose seta. J. Marshall Islands (JBJB), prolateral. K–L. Torres Strait, Darnley Island (AM), prolateral. Figures not to scale.

Fig. 6. Labahitha fuscata (Nakatsudi, 1943) comb. nov., endogyne, dorsal, lactic acid cleared. A. Brunei, Tutong (JK 110416.1907). B. Same locality (JK 130213.1101). C. Papua New Guinea, Bismarck Islands, habitus, dorsal (ZMB). D. New Caledonia, Poum (AMNH IFM-0918). E. Palau, Koror (JBJB) (not to scale).

Fig. 29. Labahitha spp., endogyne, dorsal. A. Labahitha garciai (Simon, 1892) comb. nov. from Singapore, Pulau Ubin (JK 150310.0002). B. Paratype of Pritha sechellana Benoit, 1978 from Seychelles, Praslin (MRAC 143106). C. Labahitha fuscata (Nakatsudi, 1943) comb. nov. from Brunei, Tutong (JK 110416.1907). D–E. Labahitha marginata (Kishida, 1936) comb. nov. D. Costa Rica, San José, Parque Nacional La Cangreja (INBIO 79582). E. Paratype of Filistata bakeri Berland, 1938 from Vanuatu, Espiritu Santo (MNHN AR 3437). F. Holotype of Labahitha platnicki sp. nov. from New Caledonia, Nord, Foué (AMNH IFM-0890). Scale bars = 0.1 mm.

Fig. 1. Geographical distribution of Labahitha Zonstein, Marusik & Magalhaes, 2017. A. L. fuscata (Nakatsudi, 1943) comb. nov. B. Labahitha spp. (black triangle = L. gibsonhilli (Savory, 1943); white circle = L. nicobarensis (Tikader, 1977) comb. nov.; white square = L. oonopiformis (Bristowe, 1938); white star = L. platnicki sp. nov.; white triangle = L. ryukyuensis (Ono, 2013) comb. nov.; black star = L. incerta sp. nov.; black diamond = L. littoralis (Roewer, 1938) comb. nov.; black square = L. insularis (Thorell, 1891) comb. nov.; black circle =L. sundaica comb. nov. C. L. garciai(Simon, 1892) comb. nov. D. L. marginata (Kishida, 1936) comb. nov. Scale bars = 1000 km.