Jacaena mihun, Deeleman-Reinhold, Christa, 2001

Deeleman-Reinhold, Christa, 2001, Forest Spiders of South East Asia With a revision of the sac and ground spiders (Araneae: Clubionidae, Corinnidae, Liocranidae, Gnaphosidae, Prodidomidae and Trochanteriidae)., Forest Spiders of South East Asia With a revision of the sac and ground spiders- Family Liocranidae, Leiden, Netherlands: Brill Leiden; Boston; Köln, pp. 400-505 : 467-470

publication ID

https://doi.org/ 10.5281/zenodo.814704

DOI

https://doi.org/10.5281/zenodo.5575689

persistent identifier

https://treatment.plazi.org/id/03B3FE72-C97D-FFA1-64FC-8D81DEDFFEDA

treatment provided by

Jeremy

scientific name

Jacaena mihun
status

sp. nov.

Jacaena mihun View in CoL sp. n. ( figs 786- View Figs 775 - 785 795, map 39 View Map 39 )

Type locality.— C Thailand, Prov. Nakhon Ratchasima, Khao Yai National Park.

Type material.— Holotype ♂ from the type locality, appr. 1000 m, secondary forest, leaf litter, 25.x. 1985, PR. Deeleman; paratypes: 1 ♀, same data, Eucalyptus litter, 8.xi. 1987 ; 1 9, same data, pitfall trap behind lawn, 2-9.iii. 1986, PR. and C.L. Deeleman .

Other material. — N Thailand, Chiang Mai, Mae Hia, at the foot of Doi Suthep Mountain, secondary deciduous forest and teak plantation , in pitfall traps, 1 ♂ ( MHNG), 17- 24.i. 1988 , 1 ♀ ( MHNG), 7-13.ii. 1988 , 1 ♀ ( CD), 4-28.ii. 1992, P. Schwendinger ( MHNG ).

Diagnosis.— J. mihun differs from distincta by having the PME close together, almost touching, the surface of the carapace densely covered by granulations, the presence of a thoracic pit, the pedicel not fused with the sternum, further by the dorsal pattern of the abdomen which exhibits a series of transverse white strips. The male palp has a much shortened embolus and small conductor. The epigyne differs by the median position of the openings. The number of ventral spines (9 pair on tibia I, 6 on metatarsus I) is higher than in any studied species of Sesieutes and in Jacaena distincta .

Description.— MALE, holotype. Total length 5.60 mm (male from Mae Hia 7.20 mm). Carapace length 2.70 mm, width 2.15 mm, height at coxae II 0.90 mm, head width 1.20 mm, width eye group 0.85 mm; abdomen 2.75 mm long, 1.40 mm wide. Leg lengths: legs I lost, leg II 7.90 mm (2.25-2.85-1.65-1.15), leg III 7.00 mm (1.95-2.25-1.70-1.10), leg IV 9.45 mm (2.65-3.15-2.60-1.05), palp 0.90-0.30-0.35- 1.15 mm. Carapace covered with fine granules, orange brown with darker radiating streaks, sternum and legs yellow, sternum with granules, femora dark, tibia I and IV dark with light apical ring, rest of legs paler. Abdomen dorsally dark with in the middle a pair of white triangular spots, followed by 3 transverse white bars and a white area above spinnerets; ventrally ( fig. 788 View Figs 775 - 785 ) a longitudinal broad white band with in the middle a dark stripe, and on either side about 10 white spots in a row; flanks dark with diagonal white bar. Thoracic groove a round pit. Both eye rows faintly procurved, AME slightly larger than ALE, ocular quadrangle longer than wide, AME half their d apart, almost juxtaposed to ALE; d PME = d PLE, PME oval, separated by less than 1/2 their d, more than their d from the laterals. Clypeus 1 AM eye diameter, clypeal lobe faint. Mouthparts and sternum fig. 792 View Figs 791 - 795 , chelicerae ( fig. 789 View Figs 775 - 785 ) with 4 promarginal and 2 retromarginal denticles, the latter far apart. Pedicel not fused with sternum. Leg spination: leg I in the N Thailand male: femur with 1-1pl, tibia with 9 pair ventrally, other femora spineless, tibia II in holotype with 7pv, 6rv in holotype, 8pv, 7rv in the specimen from the North, tibia III and IV with 0-0, 1-1v or l-2v, 1pl and an additional apical ventral pair in leg IV; metatarsus I with 6 pair, metatarsus II with 4 pairs, metatarsus III and IV with 1-1v, 1-0pl and 1-0rl. Dorsal scutum covering half of abdomen. Palp figs 790­ View Figs 775 - 785 791 View Figs 791 - 795 (bulb tilted to show the apical embolus): tegulum enlarged, duct not clearly visible, embolus much shortened and rigid, flattened and chitinized, conductor concave, forming a groove in which rests the tip of the embolus.

FEMALE, paratype. Total length 6.20 mm (females from Mae Hia, N Thailand, 8.50 and 8.20 mm). Carapace length 2.20 mm, width 1.90 mm, height at coxae II 0.75 mm, head width 1.00 mm, width eye group 0.75 mm; abdomen 3.30 mm long, 1.85 mm wide, epigyne 0.55 mm wide, 0.60 mm long. Leg lengths: leg I 8.15 mm (2.10-3.00-1.95-1.10), leg II 7.00 mm (1.90-2.50-1.60-1.00), leg III 6.10 mm (1.50-2.10-1.50-1.00), leg IV 8.90 mm (2.45-2.80-2.50-1.15), palp 0.80-0.35-0.50- 0.80 mm. Carapace, eyes, sternum and legs as in male; abdomen (figs 786-787) dark with 5 transverse white bands and a white area above spinnerets. No dorsal scutum, epigastric scutum present. Leg spination: femur I with 3 strong prolateral spines distally (2 in subadult male), other femora spineless, ventral surface of tibiae I and II flattened, with 8pv and 7rv strong spines in leg I (9 pairs in the females from Mae Hia), 7pv, 6 rv in leg II, tibia III and IV with 1-2 or 2-2v and an additional apical ventral pair in leg IV; metatarsus I with 5 pairs of ventral spines, metatarsus II with 4 pairs, metatarsus III with 2-0v and 1-1 pl, metatarsus IV with 1-1v, 1-0pv and 1- Orv. Spinnerets as in fig. 793 View Figs 791 - 795 . Epigyne ( fig. 794 View Figs 791 - 795 ) consisting of a pair of round openings in the centre and for the rest meandering ducts shimmering through. Vulva ( fig. 795 View Figs 791 - 795 ) a long sausage-like winding canal without apparent spermathecae.

Distribution.— Found in secondary forest and plantations in C and N Thailand.

Etymology. — The rice noodle mihun, a basic food item in Thailand, was chosen because of its resemblance to the twisting serpentine tubing in the vulva.

MHNG

Switzerland, Geneva, Museum d'Histoire Naturelle

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Liocranidae

Genus

Jacaena

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