The millipede genus Epanerchodus Attems, 1901 in continental China, with descriptions of seven new cavernicolous species (Diplopoda, Polydesmida, Polydesmidae)
Author
Liu, Weixin
Author
Golovatch, Sergei
text
Zootaxa
2018
2018-08-14
4459
1
53
84
journal article
29036
10.11646/zootaxa.4459.1.2
acdf8f3d-d29f-463e-a431-191275b69a80
1175-5326
1458336
67E956AB-04B1-4EF7-8CC0-E152F95D0563
Epanerchodus parvus
,
new species
Figs 10–11
.
Material examined
:
Holotype
male (
SCAU
eGZ7-1) from
China
,
Guizhou Province
,
Qiandongnan Autonomous Prefecture
,
Cenggong County
,
Pingzhuang Town
,
Wanfuchangcheng Dong Cave
,
29.VI.2014
, colls:
Mingyi Tian
,
Weixin Liu
,
Haomin Yin
,
Sunbin Huang
and
Xinhui Wang
.
Paratypes
:
8 males
,
20 females
(
SCAU
eGZ7-2), same data as the
holotype
.
Diagnosis
: Adult males of
E. parvus
n. sp.
are distinct from other
Epanerchodus
species based on the following combination of characters: (1) body small (
ca
13–16 mm
); (2) collum broader than head (
Fig. 10A
); (3) gonopodal clivus broadly triangular; (4) endomere at base with a small, digitiform, lateral process (
p
), while its tip beak-shaped and denticulate near apex (
Fig. 11
).
The former character is similar to that observed in
E. gladiatus
n. sp.
,
E. chutou
n. sp.
(both from caves in
Guizhou
,
China
) and
E. fuscus
(from
Yunnan
,
China
). However,
E. parvus
n. sp.
is distinguished not only in gonopodal structural details, but also by the narrower body: widths of pro- and metazonae 0.8–1.0 and
1.3–1.5 mm
vs.
clearly broader in
E. gladiatus
n. sp.
,
E. chutou
n. sp.
and
E. fuscus
: widths of pro- and metazonae 1.2–1.3 and 2.5–3.0, 1–1.2 and 2.0, and 2.3 and 4.0 mm, respectively.
Description
: Based on
type
specimens. Lengths of body
ca
13.5–15.5 mm
(males) or
15–17 mm
(females), widths of pro- and metazonae 0.8–1.0 and
1.3–1.5 mm
(males) or 1.01–1.2 and
1.7–1.8 mm
(females).
Coloration
: in alcohol generally pallid. Mouthparts and gonopodal telopodites light yellowish.
Body
: Adults with 20 rings. Width: collum <head = rings 2–3 <4 <5–15, thereafter body gradually tapering towards telson.
Head
: clypeus densely pilose, vertex sparsely setose, epicranial suture conspicuous (
Fig. 10B
). Antennae long, reaching behind posterior margin of ring 3 when extended posteriorly, slightly clavate (
Figs. 10A, B, G
).
Exoskeleton
: Collum fanshaped, with a lateral incision on each side (
Fig. 10A
). Paraterga narrow (
Fig. 10
), midbody paraterga extend metatergite to
ca
1.5x width of prozonite. Paraterga on collum and rings 2–4 clearly upturned dorsally above a faintly convex dorsum, other paraterga flat. From ring 10 on, caudolateral corners of paraterga increasingly acuteangled, sharper and pointed on rings 15–19 (
Fig. 10D
). Integument shining, translucent, prozonae very delicately alveolate. Limbus regularly denticulate. Constriction between pro- and metazonae narrow, shallow and smooth. Metatergal sculpture faint, with three irregular transverse rows of setigerous, polygonal bosses. Sulcus between front and middle rows of setae a little deeper than that between middle and caudal rows. Tergal setae invisible. Three or four faint setigerous incisions at lateral margins of poreless and pore-bearing rings, respectively. Pore formula normal: 5, 7, 9, 10, 12, 13, 15–19, ozopores evident, dorsal, clearly set off from lateral margin and located between last and penultimate marginal incisions. Epiproct short, conical, pre-apical lateral papillae small. Hypoproct subtrapeziform, with two setigerous papillae. Pleurosternal carinae small, present only on ring 2. Sterna sparsely setose, cross-shaped impressions shallow. Legs long and slender (
Fig. 10
), about 2.0–2.2 times as long as body ring height in both sexes, without sphaerotrichomes or sternal cones, prefemora not bulging laterally.
Gonopods
: slender (
Fig. 11
). Telopodite mostly suberect. Prefemur densely setose and nearly half the length of telopodite. Clivus (
cl
) broadly triangular. Endomere (
en
) tip beak-shaped, denticulate near apex. Endomere at base with a small, digitiform, lateral process (
p
). Seminal groove starting mesally, then recurving laterad to run into an accessory seminal chamber, the latter opening on a hairy pulvillus. An exomere absent.
FIGURE 10.
Epanerchodus parvus
n. sp.
, male paratype.
A
: anterior part of body, dorsal view.
B
: anterior part of body, ventral view.
C
: midbody rings, dorsal view.
D
: posterior part of body, dorsal view.
E
: midbody rings, ventral view.
F
: posterior part of body, ventral view.
G
: habitus, dorsal view. Scale bar: A–F, 0.1 mm; G, 0.2 mm.
FIGURE 11.
Epanerchodus parvus
n. sp.
, male paratype.
A
: left gonopod, mesal view.
B
: left gonopod, lateral view. Abbreviations: cl = clivus; en = endomere; p = process.
Note
: Because of the long slender antennae and legs, and a depigmented cuticle, this species is most likely a troglobite.
Etymology
: To emphasize the small size of this species; masculine adjective.