Ctenus ramosus Thorell 1887

Jäger, Peter, 2012, Asian species of the genera Anahita Karsch 1879, Ctenus Walckenaer 1805 and Amauropelma Raven, Stumkat & Gray 2001 (Arachnida: Araneae: Ctenidae), Zootaxa 3429 (1), pp. 1-63 : 14-17

Ctenus ramosus Thorell 1887

Figs 39 , 47–58

Ctenus ramosus Thorell 1887: 291 (description of male; holotype, MCSN, examined; 2 paratypes, ZMH, not examined). Thorell 1897: 15 (description of female; 1 female, MCSN, examined)

Ctenus trabifer Thorell 1887: 288 (description of immature female; holotype not examined)

Type material. Holotype male ( MCSN), Burma, Kachin State, Bhamò [24°15'13.85"N, 97°14'3.23"E], Fea leg. 1885, examined.

Additional material examined. 1 female ( MCSN), Burma, Kachin State, Teinxò [= Teinthaw; 24°23'49.38"N, 97°15'9.96"E, ca. 16 km directly N of Bhamò], Fea leg. [one label reads: Teinxò sul Mulé-ciaung , 20 a 25 chilom(etri). sett(entrionale). di Bhamò = Teinthaw south of the river (=chaung) Mule , 20 to 25 km north of Bhamò ] .

Diagnosis. Medium-sized Ctenidae (total length male 13.2). Together with C. cladarus spec. nov. distinguished from other Ctenus spp. in this paper by the modified tip of RTA, which breaks easily ( Figs 48–49 ). RTA tip with dorsal thorn (with cup-like structure in C. cladarus sp. nov.). Distal tip of tegular apophysis bent at right angle in ventral view ( Fig. 48 ). Females may be recognised by their complex lateral teeth with unusually broad base and the anteriorly extended epigynal field (but see also note below) ( Fig. 50 ).

Redescription. Male (holotype). PL 7.0, PW 5.5, AW 2.6, OL 5.5, OW 3.8. Spination of palp and legs: palp 14(5)1, 100, 1121; femora I p021, d111, r112, II–III p112, d111, r 112, IV p112, d111, r012; patellae 101; tibiae I– II p010, d111, r110, v22222, III–IV p11, d111, r11, v222; metatarsi I–II p111, r111, v223, III p112, d010, r112, v222, IV p112, d010, r112, v21212. Chelicerae with 3 promarginal, 4 retromarginal teeth, and with patch of several tiny denticles along entire furrow. Retromargin of chelicerae close to fang base with 5–7 bristles, these situated subdistally. Ventral coxae with long setae.

Palp as in diagnosis ( Figs 47–49 ). Proximal cymbium without large distinct extensions. RTA base with parallel margins in ventral view; RTA with complex tip. Cymbium tip slightly conical, retro-proximally with tiny extension. Embolus arising at 8.30-o’clock-position, short, curved, its tip situated sub-centrally. Conductor arising at 11.30-o’clock-position in distal half. Tegular apophysis arising in 6.30-o’clock-position, large, i.e. larger than half length of tegulum.

Bhamò; 3 Mt Victoria ; 4 Palon; 5 Malewoon). 6 Baoxing, Sichuan, China . 7–12 Laos (7 Ban Tavan, Luang Nam Tha; 8 Phou Hiphi, Oudomxai; 9 Nong Khiao, Luang Prabang; 10 Luang Prabang town; 11 Vang Vieng, Vientiane; 12 Tad Fane/Paksong, Champasak) . 13 Palembang, Sumatra, Indonesia .

Colour ( Figs 53–55 ). Deep yellowish-brown. Dorsal prosoma with light median band, fovea distinctly marked with black. Sternum yellowish-brown with margins darkened. Chelicerae as prosoma. Legs without distinct pattern. Dorsal opisthosoma with lighter heart region, lateral opisthosoma indistinctly spotted, ventral opisthosoma darker with part anterior to epigastric furrow light, without distinct pattern, spinnerets lighter.

Female. PL 9.2, PW 7.0, AW 4.5, OL 9.4, OW 6.3. Spination of palp and legs: palp 131, 1(0)00, 1111, 1013; femora I p021, d111, r111(0), II p112(1), d111, r111(0), III p112, d111, r 112, IV p112(1), d111, r002; patellae I–II 000, III–IV 101; tibiae I–II v22222, III–IV p11, d111, r11, v222; metatarsi I–II v222, III p112, d010, r112, v222, IV p112, d010, r112, v2122. Chelicerae with 3 promarginal, 4 retromarginal teeth, and with patch of several tiny denticles along entire furrow. Retromargin of chelicerae close to fang base with 13 distal bristles and 5 subdistal bristles. Ventral coxae with long setae.

Copulatory organ as in diagnosis ( Figs 50–52 ). Epigynal field longer than wide, with a pair of tiny patches anteriorly, clearly separated from the field, and a second pair of larger elongate patches, fused to the field on the right side; with two pairs of slit sensilla laterally. Anterior part of median plate narrow as bottle-neck, posterior part

Colour ( Figs 56–58 ). As in male, but reddish-brown. Ventral opisthosoma with few light spots posterior to epigastric furrow.

Distribution. Known only from the type locality, Burma, Bhamò ( Fig. 39 : 2).

Notes. Ctenus trabifer Thorell 1887 was synonymised with C. ramosus by Thorell (1897) and listed in this sense in Roewer (1954: 1453). Bonnet (1956: 1291) listed this synonymy vice versa, i.e. C. ramosus as synonym of C. trabifer . Since the immature female holotype of C. trabifer has been collected from the same locality as the holotype of C. ramosus , it is most likely that both specimens are conspecific and names are synonymous. It is not clear whether the adult female described by Thorell (1897) and re-described here is indeed conspecific with the holotype male of C. ramosus .

The female of C. meghalayensis as illustrated by Tikader (1976) exhibits an epigyne similar to that of C. ramosus . The species status or possible synonymy of these two species can only be reliably considered by a thorough analysis of material of both sexes.

Figures

FIGURE 39. Records of Ctenus spp. in South and Southeast Asia. 1 Between Chitre and Chandrung, Nepal. 2–5 Burma (2

FIGURES 47–52. Ctenus ramosus Thorell 1887. 47–49 Holotype male from Burma (Bhamò), left male palp (47 prolateral,

FIGURES 53–58. Ctenus ramosus Thorell 1887. 53–55 Holotype male from Burma (Bhamò), 56–58 Female from Burma (Teinthaw). 53, 56 Habitus dorsal. 54, 57 Habitus, ventral. 55, 58 Habitus, lateral.