Cyphoderopsis thachana, Jantarit, Sopark, Satasook, Chutamas & Deharveng, Louis, 2013

Jantarit, Sopark, Satasook, Chutamas & Deharveng, Louis, 2013, The genus Cyphoderopsis Carpenter (Collembola: Paronellidae) in Thailand and a faunal transition at the Isthmus of Kra in Troglopedetinae, Zootaxa 3721 (1), pp. 49-70 : 58-61

Cyphoderopsis thachana sp. nov.

( Fig. 5 )

Type material (point C 1 in Fig. 1 ). Holotype male and five paratypes on slides (one female; four probably subadult or female adult, genital plate not seen clearly): THAILAND: Surat Thani Province: Tha Chana district: Tham Yai, 13.vii.1987, in cave, Berlese extraction, L. Deharveng & N. Giani leg. (sample # THA-SUT-002). Coordinates: 99.189119°E, 9.539795°N, altitude about 20 m.

Holotype and two paratypes in PSU; three paratypes (including one female) in MNHN.

Description. Habitus relatively stout. Body length 1.1–1.4 mm excluding antennae and furca. Lengths of body parts in Table 2 . Fourth abdominal segment 6–7 times as long as the third one along axis. Furca well developed, 1.8–2.0 times shorter than body length. Body colour white. Eyes absent, no ocular patch. Scales present on antennae, head, body and furca, absent on ventral tube.

Mouthparts. Mandible head with 4 (left) and 5 (right) teeth. Maxilla head stocky, with tridentate claw and 6 ciliate lamellae. Labial basis chaetotaxy: M1M2ReL1l2, all mesochaetae, except l2 which is laterally displaced and mic-size, with R shorter than M2 and e smooth ( Fig. 5 A). Outer maxillary lobe with one basal chaeta, a simple palp and two sublobal hairs ( Fig. 5 B). Labral formula 4/554, with 4 prelabral chaetae bent and ciliate, labral chaetae smooth and acuminate; distal part of labrum adorned with two strong central pointed spines dorsally and a complex structure constituted of two asymmetrical combs and two small adjacent curved rods ventrally ( Fig. 5 C).

Antennae. Antennae about 1.5 times as long as head. Scales present dorsally on Ant.I and II. Ordinary chaetae as ciliate mes, numerous on all antennal segment (types 1, 2, 4 on Fig. 5 D), and a few smooth basal mic on Ant.I, II and III (type 11 on Fig. 5 D); S-chaetae of various morphology, present on all antennal segments (types 3, 7, 8, 9, 10, 12, 13 on Fig. 5 D). Types 5 and 6 may correspond to smooth and to very slightly serrated variants of a same type of chaeta. Ant.IV not subdivided or annulated, apical bulb absent, subapical organ rather long, thick, slightly thickened distally.

Dorsal chaetotaxy. Dorsal chaetae of 6 types: ciliate, very long and thin tric; serrated or ciliate mac, of various length and thickness; smooth and rather thin mes; modified mes around tric (enlarged with special morphology); sens of 2 types: dark, short, straight, pointed (type 1) and longer, thinner, hyaline (type 2) ( Fig. 5 F).

Dorsal macrochaeta and pseudopore arrangement illustrated on Fig. 5 E. Trichobothria formula 0, 0/0, 2, 3, 3. Macrochaeta formula 0/4, 0/0, 2, 4, 4 (chaeta posterior to T3 not developed in mac). Dorsal pseudopore formula 1, 1/1, 1, 1, 1+4.

Dorsal chaetotaxy of head similar to that of C. phangnga sp. nov. No dorsal mac on head except an antennobasal row of 6–8 mac on each side; cephalic mes short, feebly serrated, equal, symmetrically arranged. A pair of thin trichobothria-like chaetae present antero-laterally on head (as on Figs 3 B, C). Suture zone visible on head (as on Fig. 3 B). Thin serrated mes present on all tergites in uncertain number. Th.II with 4+4 central mac and 2+2 antero-lateral sens (1+1 sens1 and 1+1 sens2) ( Fig. 5 F). Th.III without mac, sens not seen. Abd.I without mac, with 1+1 sens1. Abd.II with 2+2 tric, 1+1 sens2 near internal tric, 1+1 mac external to internal tric, 1+1 mac external to external tric, and several modified mes around tric ( Fig. 5 E). Abd.III with 3+3 tric, 4+4 mac (1+1 near internal tric, 3+3 near postero-external tric), several modified mes around tric, and 2+2 sens located like in C. phangnga sp. nov. (1+1 sens2 anterior to internal tric and 1+1 sens1 posterior to external tric). Abd.IV with 3+3 tric (2+2 anterior, 1+1 postero-lateral), 4+4 mac (1+1 anterior to pseudopores, 1+1 near T2, 1+1 near T3, 1+1 posterior), and several mac external to the anterior trichobothrial complex T1-T2; several modified mes around T1 and T2; presence of short to medium-size chaetae, not easily assignable to mes or S-chaetae. Abd.V with 2+2 sens2. Abd.VI chaetotaxy not analyzed.

Legs. Tibiotarsus chaetotaxy mostly composed of large ciliate mesochaetae, finely ciliate chaetae internally, 2– 3 shorter dorsal ciliate mes (1/5 of the long ones), one thick smooth ventro-subapical chaeta on hind tita, a dorsoapical tenent hair rather thick, smooth and acuminate on all tita, and 2–3 smooth pointed dorsal mic, the distal one close to the tenent hair; distal row of 10 serrated chaetae arranged obliquely on all legs ( Figs 5 G, H). Claw small, 7.5–8.5 times shorter than tita; with 2 teeth at 55% and 75% of inner edge, a small dorsal tooth basally and a pair of inner basal teeth of unequal size ( Fig. 5 H). Unguiculus pointed, narrow, lanceolate and elongate, more than half as long as claw, its external edge smooth ( Fig. 5 H).

Ventral tube. With 4+4 long serrated mac anteriorly, at least 5 smooth mes on each lateral flap ( Fig. 5 I), and a combination of long and short ciliate mes posteriorly (exact number uncertain from our specimens).

Furca. Tenaculum with 4 teeth on each branch and a strong, densely serrated, bent distally chaeta. Manubrium about as long as or slightly longer than mucrodens. Dens 4.5–5.0 times as long as mucro ( Fig. 5 J). Manubrium with dorsal ciliate mes (none smooth) arranged in two longitudinal stripes laterally separated by a glabrous axial stripe, distal area with 4+4 mes and 2+2 pseudopores; ventrally with oval scales and a distal group of 2–3+2–3 ciliate mes. Dens elongate, hairy, with 2 dorso-lateral rows of spines, sometimes asymmetrical; the external row with 14–15 thick serrated spiny chaetae, blunt apically; the internal row with 23 to 25 spines, subequal, pointed, smooth and shorter than the external ones in adult ( Fig. 5 J). Dorsally between the two spine rows, one (distally) to 3 (proximally) irregular lines of ciliate chaetae of various length. Scales on ventral and ventro-lateral sides of dentes, arranged in multiplets of 3–4 scales, more visible distally. Scales elongate, enlarged distally, of various morphology (see Fig. 4 G). Mucro rather stout and rather long, straight, with 3 main teeth, the apical one blunt, the subapical one small and acute, the dorso-basal one acute and longer, with 1–4 toothlets basally ( Fig. 5 K).

Occurrence. Only known from type locality.

Habitat. Cave. The new species was formerly recorded as Troglopedetes sp. from Tham Yai (Deharveng & Bedos 1988). This small cave has 196 m of passages in a 6 km-long isolated limestone outcrop about 4 km SE of Tha Chana. The specimens were found in dark humid oligotrophic micro-habitats of the westernmost part of the cave, together with one specimen of another slightly troglomorphic species of Cyphoderopsis (thinner claw devoid of distal inner tooth). A species of Oncopodura Carl & Lebedinsky 1905 was also collected in this cave.

Etymology. The species name is taken from the type locality.

Remarks. Cyphoderopsis thachana sp. nov. differs from C. phangnga sp. nov. by the characters listed in Table 5; in particular, this new species usually has a longer body (1.1–1.4 versus 0.9–1.2) and two inner teeth on unguis (versus one in C. phangnga sp. nov.); tenent hairs of both species are acuminate but they are thicker in C. thachana sp. nov.; ventral tube has 4+4 anterior mac (versus 3+ 3 in C. phangnga sp. nov.); the ratio dens: mucro is higher than in C. phangnga sp. nov. (5 versus 3–4) and there are more spines in the dorso-lateral rows of the dens in this new species (internal: 14–15 versus 10–12; external: 23–25 versus 19). It should be stressed however that we lack information on variability in number of dental spines.

Figures

FIGURE 1. Distribution of Paronellidae in sampled caves of Thailand. Black circles, caves with Cyphoderopsis. C 1, C. thachana sp. nov.; C 2, C. khaophang sp. nov. and C. cavicola sp. nov.; C 3, C. phangnga sp. nov.; C 4, Cyphoderopsis unidentified species (Tham Khao Noi, Phatthalung prov.); C 5, Cyphoderopsis unidentified species (Tham Peung, Surat Thani prov.). Half plain red circles, Troglopedetes records. T 1, T. maungonensis Deharveng & Gers, 1993; T 2, T. maffrei Deharveng & Gers, 1993; T 3, T. microps Deharveng & Gers, 1993; T 4, T. longicornis Deharveng & Gers, 1993; T 5, T. centralis Deharveng & Gers, 1993; T 6, T. dispersus Deharveng & Gers, 1993; T 7, T. multispinosus Deharveng & Gers, 1993; T 8, T. convergens Deharveng & Gers, 1993; T 9, T. paucisetosus Deharveng & Gers, 1993; T 10, T. calvus Deharveng & Gers, 1993; T 11, T. fredstonei Deharveng, 1988 and T. leclerci Deharveng, 1990; T 12, Troglopedetes unidentified species (Tham Phakok, Tak prov.); T 13, Troglopedetes unidentified species (Tham Mon, Kanchanaburi prov.); T 14, Troglopedetes unidentified species (Tham Erawan, Lamphun prov). Empty blue circles, caves where no species of Cyphoderopsis or Troglopedetes have been found.

FIGURE 3. Cyphoderopsis phangnga sp. nov., continued, (A) Two types of S-chaetae on tergites; (B) Dorsal chaetotaxy of head; some fallen mes may have been unnoticed; (C) Antero-lateral trichobothrium-like chaeta on head (X); (D) Chaetotaxy of tergites, left side (M, macrochaeta; lateral group of macrochaetae encircled by dotted line; mes number not complete); (E) Trichobothrial complexes of Abd. II – III, left side; (F) Trichobothrial complex of Abd. IV (T 1 and T 2), left side. Filled black circles on Abd. II-Abd. IV trichobothrial areas: sockets of modified mesochaetae.

FIGURE 4. Cyphoderopsis phangnga sp. nov., continued, (A) Tibiotarsus II showing three smooth pointed dorsal mic and tenent hair (ordinary chaetae not drawn); (B) Foot complexand distal part of tibiotarsus III; (C) Ventral tube in antero-lateral view; (D) Posterior side of ventral tube; (E) Dens and mucro (subadult); (F) Different types of dental chaetae: ordinary chaetae (1 – 4) and spines (5 – 7); (G) Different types of scales on dens (1 – 3) and on ventral side of manubrium (4).

FIGURE 5. Cyphoderopsis thachana sp. nov. (A) Chaetotaxy of basal area of labium; (B) Outer maxillary lobe, right side; (C) Labrum, distal part in ventral view with two lateral combs and two central curved rods; (D) Different types of antennal chaetae (see text for chaeta type numbering); (E) Tergite chaetotaxy, left side (mes number not complete); (F) Two types of S-chaetae on Th. II; (G) Foot complex and distal part of tibiotarsus III; (H) Claw and distal part of tibiotarsus III; (I) Anterior side of ventral tube; (J) Dens and mucro; (K) Mucro.

Tables

TABLE 2. Cyphoderopsis thachana sp. nov., measurements in µm from subadult paratype (# THA- SUT- 002 slide 01); body length includes head.

Body	Head	Ant	Ant.I	Ant.II	Ant.III	Ant.IV	Th.II	Th.III
1356	371	536	57	143	86	250	136	100
Abd.I	Abd.II	Abd.III	Abd.IV	Abd.V	Abd.VI	Man	Dens	Mucro
43	36	86	457	79	50	357	278	57