The genus Cyphoderopsis Carpenter (Collembola: Paronellidae) in Thailand and a faunal transition at the Isthmus of Kra in Troglopedetinae
Author
Jantarit, Sopark
Author
Satasook, Chutamas
Author
Deharveng, Louis
text
Zootaxa
2013
3721
1
49
70
journal article
10.11646/zootaxa.3721.1.2
d9159fd2-66d7-46dc-8ddd-0f9777c9fb1a
1175-5326
285105
935F1F1B-F09B-4BD0-A102-8FE8515CDC04
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).
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.
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 |
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.