Jacaena peculiaris sp. nov.

(Figures 2H, 6D, 7F, 14D–E)

Type material

Holotype: ♀, Thailand: Nan Province: Tha Wang Pha District, Nanthaburi NP, Doi Wao, evergreen hill forest near the summit, 1300–1550 m, extraction of leaf litter samples, 7 December 2005, P. Dankittipakul leg. (MHNG, PDC 4640).

Paratypes: Same data as holotype, 2♀ (THNM, PDC 4654) .

Diagnosis

Unlike most females of Jacaena, J. peculiaris sp. nov. can be readily distinguished by the very enlarged spermathecae (Figures 7F, 14E), a character that is shared among the females of Teutamus species. However, females of Jacaena can be separated from those of Teutamus in the lack of the dorsal scutum and their epigastric scutum is not protruding and forming an elongated collar; the spination of legs and other somatic characters are also different from Teutamus .

Etymology

The specific epithet refers to the peculiar shape of the spermathecae, which are the largest among Jacaena females (Latin, pecularis = belonging exclusively to one person).

Description

Female (holotype). Total length 6.1. Carapace 2.8 long, 2.2 wide. Opisthosoma 3.3 long, 1.7 wide. Eye sizes and interdistances: AME 0.13; ALE 0.13; PME 0.11; PLE 0.15; AME–AME 0.08; AME–ALE 0.05; PME–PME 0.11; PME–PLE 0.15. MOQ 0.33 long; front width 0.31; back width 0.33. Leg formula 4123. Spination. Leg I: femur 1–1pl; tibia 8pl 7rl; metatarsus 5pl 5rl. Leg II: tibia 7pl 6rl; metatarsus 4pl 4rl. Leg III: tibia 1–1–1v 1pl 1rl; metatarsus 1–1v 1rl. Leg IV: tibia 1–1–1–1–2v 1–1rl; metatarsus 1–1–1–1–1v 1pl 1rl. Leg measurements: Leg I 7.5 (2.2, 0.8, 2.0, 1.6, 0.9); II 6.8 (2.0, 0.9, 1.5, 1.5, 0.9); III 5.6 (1.6, 0.7, 1.2, 1.3, 2.8); IV 8.8 (2.3, 0.9, 2.0, 2.5, 1.1).

Colouration and pattern (Figure 2H): Carapace dark reddish-brown; integument finely granulated. Fovea obsolete. Chelicerae, sternum, labium and gnathocoxae dark reddish-brown. Legs I–II dark brown, femora darkest, tibiae yellow distally; legs III–IV orange-brown, femora brown. Opisthosoma elongate-ovoid; dorsum grey, with paired, enlarged pale patches, followed by broad pale band and pale area above spinnerets.

Copulatory organ (Figures 6D, 7F, 14D–E): Copulatory orifices (Figure 14D) circular, anterior margin poorly defined, posterior margin represented by elevated ridge, connected to bell-shaped, semi-transparent chamber (Figure 6D). Insemination ducts tubular, elongated, slender, opening to mesolateral surface of enlarged spermathecae (Figure 14E). Spermathecae more or less reniform, with large glandular pore situated anteriorly (Figures 6D, 14E). Secretory ampullae attached to apex of semi-transparent chamber (Figure 6D).

Male. Unknown.

Natural history

Types of J. peculiaris sp. nov. were collected from evergreen hill forests near the summit of Doi Wao where the humidity is constantly high (> 85% relatively humidity), even during summer.

Distribution

Known only from the type locality, Nan Province, northern Thailand.