Six new species of Thalassaphorura (Collembola, Onychiuridae) from southern China, with a key to world species of the genus
Author
Sun, Xin
Author
Chen, Jian-Xiu
Author
Deharveng, Louis
text
Zootaxa
2010
2627
20
38
journal article
10.5281/zenodo.198236
b083b37e-88b9-4dd2-b331-269183157d79
1175-5326
198236
Thalassaphorura grandis
sp. nov.
Figs 1
,
15
,
21
,
27
&
33
,
Tab. 1
.
Type
material.
Holotype
female and 51
paratypes
female on slide, about 800
paratypes
in alcohol,
China
: Guangxi: Huanjiang: Min Li forest (
E 107.96647°
,
N 25.09935°
):
14.iii.2005
, litter, berlese after sifting, M. Chen leg. (CHIgx05–109); ibid: 6
paratypes
on slide, more than 200
paratypes
in alcohol,
14.iii.2005
, litter and soil, berlese, L. Deharveng & A. Bedos leg. (CHIgx05–100, –102, –104); ibid: near Dong Qiao Dong: 4
paratypes
on slides,
5.xi.2009
, litter, sifting and berlese, Tian Mingyi leg. (CHIgx09–080); ibid: near Hong Dong (Alt.
680m
,
E 107.9747°
,
N 25.11825°
): 1
paratype
on slide, about 60
paratypes
in alcohol,
13.ii.2009
, litter, sifting and berlese, L. Deharveng leg. (CHIgx09–004); ibid: near a shaft (
E 107.97692°
,
N 25.11945°
): 4
paratypes
on slide, about 150
paratypes
in alcohol,
12.iii.2005
, litter, berlese after sifting, L. Deharveng & A. Bedos leg. (CHIgx05–078).
Holotype
and 33
paratypes
on slide and many
paratypes
in alcohol in
NJU
; 33
paratypes
on slide and many
paratypes
in alcohol in
MNHN
.
Other material.
Longzhou: Nonggang Nature Reserve: 5 on slide,
40 in
alcohol,
7.iii.2005
, soil, berlese, L. Deharveng & A. Bedos leg. (CHIgx05–067); ibid: 4 on slide,
50 in
alcohol,
7.iii.2005
, litter, berlese after sifting, L. Deharveng & A. Bedos leg. (CHIgx05–068); Yachang: forest near Yan Wu Dong (Alt.
1359m
,
E 106.43133°
,
N 24.82364°
): 2 on slide,
31.v.2007
, secondary forest with
Quercus
and
Castanopsis
, litter, berlese after sifting, L. Deharveng & A. Bedos leg. (CHIgx
07–31–03
).
Description.
Body length: females
1.4–1.6 mm
. Body shape: cylindrical, Abd. III–IV more or less broadened. Body color: white in alcohol.
Pseudocelli formula as 32/133/33343 dorsally, 11/000/01110 ventrally, subcoxa 1 of legs I, II and III with 2, 2 and 2 pso respectively (
Fig. 15
). Parapseudocelli: 1+1 on sternum of Abd. I, near base of ventral tube (
Fig. 33
). Pseudopore formula as 00/011/11110 dorsally, 00/111/000x0 ventrally.
S-chaeta not distinguishable from ordinary chaetae. S-microchaeta tiny and blunt, present on Th. II and III dorsally.
Head. Antennae short and distinctly segmented, 0.8 times as long as head. Length ratio of antennal segments I: II: III: IV = 1.0: 1.2–1.5: 1.2–1.5: 2–2.4. Ant. I with 9 chaetae. Ant. II with 13 chaetae. Ant. III sensory organ composed of 5 papillae, 5 guard chaetae, 2 small rods and 2 smooth subequal clubs; lateral ms just behind sensory organ. Ant. IV subapical organite with apex globular; basolateral ms at about 2/5 length from base. Antennal base with distinct granulation. Anterior cephalic dorsal pso situated inside antennal basal area. PAO composed of 21–23 simple vesicles arranged in 2 rows along axis of organ. Dorsal cephalic chaeta d0 present. 4+4 p-chaetae between posterior a-pso on head, p1 anterior to others. Mandible with strong molar plate and 4 apical teeth. Maxilla bearing 3 teeth and 6 lamellae. Maxillary palp simple with 1 basal chaeta and 2 sublobal hairs. Labral chaetae 4/1,4,2. Labial papillae of AC
type
, papillae A–E respectively with 1, 4, 0, 3 and 2 guard chaetae. Labium with 6 proximal, 4 (E, F, G and f) basomedian and 6 (a, b, c, d, e, e’) basolateral chaetae. Postlabial chaetae 4+4 along ventral groove.
Body chaetotaxy. Ordinary chaetae differentiated in meso- and macrochaetae, ratio Sp: m1: P1 on Abd. V = 1: 0.6: 1.3 (
Fig. 21
). Th. I with 5–7+5–7 dorsal chaetae. Th. II–Abd. III respectively with 3+3 dorsal chaetae along axial line, without dorsal axial chaetae. Abd. IV tergite with axial chaeta m0, Abd. V without axial chaeta, Abd. VI with m0 (
Fig. 21
). Th. I, II and III with 1+1, 1+1 and 1+1 chaetae respectively between legs. Subcoxa 1 of legs I, II and III with 4, 4 and 4 chaetae, subcoxa 2 with 1, 4 and 4 chaetae respectively.
Appendages. Tibiotarsi I, II and III with 18 (9, 8, 1), 18 (9, 8, 1) and 18 (9, 8, 1) chaetae. Unguis without teeth. Unguiculus slender and pointed, 0.4–0.5 times as long as inner edge of unguis, with narrow inner basal lamella (
Fig. 27
). Ventral tube with 6+6 distal chaetae and 2+2 basal chaetae, without anterior (
Fig. 33
). Furca reduced to a finely granulated area, with 4 small chaetae in two rows posterior to furcal rudiment.
Genital plate with 15–19 chaetae in females. Anal valves with numerous acuminate chaetae; each lateral valve with chaetae a0 and 2a1; upper valve with chaetae a0, 2a1, 2b1, c0, 2c1, 2c2. Anal spines set on indistinct papillae, 0.75 times as long as inner edge of hind unguis (
Fig. 21
).
Ecology.
In forest litter.
Etymology.
Named for its large body size.
Remarks.
Probably parthenogenetic (no male and
60 females
among the examined specimens). The new species is similar to
T. petaloides
(
Rusek, 1981
)
in dorsal pso formula, the presence of basal lamella on unguiculus, the number of vesicles on PAO and the number of chaetae on Th. I. They can be easily separated by the ventral pso formula (11/000/01110 in
grandis
sp. nov.
versus 11/000/01120 in
petaloides
) and S-chaeta dorsally (undifferentiated in
grandis
sp. nov.
versus differentiated in
petaloides
).