Review of the millipede family Opisotretidae (Diplopoda, Polydesmida), with descriptions of new species
Author
Golovatch, Sergei I.
Author
Geoffroy, Jean-Jacques
Author
Stoev, Pavel
Author
Spiegel, Didier Vanden
text
ZooKeys
2013
302
13
77
http://dx.doi.org/10.3897/zookeys.302.5357
journal article
http://dx.doi.org/10.3897/zookeys.302.5357
1313-2970-302-13
Martensodesmus spiniger
sp. n.
Figs 33-36
Type material.
Holotype ♂ (IZAS), China, Guangxi, Chongzuo County, Longzhou Xian, Shanglong Xiang, Lenglei, Nonggang Forest,
106.964835°E
,
22.467175°N
, litter, Berlese extraction, 07.03.2005, leg. L. Deharveng & A. Bedos (CHIgx05-062).
Paratypes
.
1 ♂ (SCAU), same locality, together with holotype; 1 ♂ (MNHN JC 345), same locality, Shanglong Xiang, Nonghang, Nonggang Forest,
106.90575°E
,
22.48617°N
, litter, sieving and Berlese extraction, 14.04.2010, leg. L. Deharveng & A. Bedos (CHIgx10-07).
Non-type
: 1 ♀ (MNHN JC 345), 1 ♂ subadult, 1 ♀ (SEM), same locality (CHIgx10-07); 1 ♂ subadult (SEM), same data as holotype (CHIgx05-062).
Diagnosis.
Differs readily fromcongeners by the presence of only two transverse rows of setae on metaterga, combined with five strong spines on the caudal face of a rather strongly curved gonopod telopodite which lacks even traces of a solenomere.
Name.
To emphasize the highly spinose gonopod telopodite.
Description.
Length of holotype ca 4.0 mm, width of midbody pro- and metazona ca 0.35 and 0.5 mm, respectively. Length of paratype ♂ ca 4.5 mm, width of midbody pro- and metazona ca 0.4 and 0.6 mm, respectively. Length of adult ♀ ca 4.7 mm, width of midbody pro- and metazona ca 0.5 and 0.6 mm, respectively. Coloration in alcohol from uniformly pallid to head, several anterior segments and following metaterga clearly infuscate, rusty reddish, increasingly poorly pigmented towards telson.
Body with 19 (♂) or 20 (♀) segments. All characters like in
Retrodesmus cavernicola
sp. n., except as follows.
Antennae broken off, but obviously medium-sized.
In width, collum << segments 2 & 3 <head = 4 ≤ 5 <6=15 (16); thereafter body gradually tapering towards telson. Paraterga medium-sized, keel-shaped (Figs 33
A-F
, 34A, 36C, D), a little better developed in ♂ compared to ♀, starting from a broadly rounded collum, mostly faintly declivous and continuing the outline of a rather convex dorsum, largely set rather high, at about
1/4
to 1/3 of midbody height, with faint shoulders frontolaterally (Figs 33
D-F
, H). Caudal corner of postcollum paraterga mostly dentiform, always clearly rounded to narrowly rounded and extending increasingly well
behind
rear tergal margin only in segments 15-18 (♂) or 16-19 (♀). Lateral edge of paraterga with 2 or 3 small setigerous indentations in poreless and poriferous segments, respectively. Ozopores evident, round, flush open on dorsal surface, mostly clearly removed from caudal margin, lying slightly above and close to caudalmost lateral incision (Figs 33B, C, F, 34B, 36C, D), lateral tooth being shorter than medial one, in segment 17 clearly lateral, in 18th caudal (Figs 36C, D). Each postcollum metatergum until 18th (♂) or 19 (♀) with 3+3, long, bacilliform setae arranged in two regular transverse rows,
only
collum and segment 18 with three transverse rows of bacilliform setae, in segment 18 (♂) or 19 (♀) both posterior rows being placed close to each other; polygonal bosses flat, barely visible, even transverse sulcus very faint (Figs 33
A-F
).
Legs rather long, but stout, ca 1.4-1.5 times as long as midbody height (♂); tarsi longest and particularly slender (Fig. 34D), sphaerotrichomes or other modified setae missing.
Gonopod telopodite (Fig. 35) clearly curved, but stout, unipartite; apical piece (a) distal to orifice of seminal groove complex, consisting of a very strong apical spine (sp) protected in its basal half by a membranous ventral velum (ve) with a faintly fringed apical margin and a similarly membranous, apically spinigerous, dorsal lobe (k); caudal face below a with three distinct spines (x, y and z), z being longest. Neither bacilliform ornamentations, nor accessory seminal chamber, nor even traces of a solenomere, nor a hairy pulvillus.
Remarks. This new
Martensodesmus
species appears to co-occur, even syntopically, together with another opisotretid,
Carlotretus triramus
sp. n., described just below. Moreover, these two species are superficially so similar that only adult males can be separated with confidence. We therefore prefer to regard the females and juveniles as non-type material.
Figure 33.
Martensodesmus spiniger
sp. n., ♂ subadult, non-type; A, D anterior body part, lateral and dorsal views, respectively B, E midbody segments, lateral and dorsal views, respectively C, F, I posterior body part, lateral, dorsal and ventral views, respectively G head, ventral view H segments 6 and 7, ventral view. - Scale bars:
A-D
, F, H, I 0.1 mm; E, G 0.05 mm.
Figure 34.
Martensodesmus spiniger
sp. n., ♂ subadult, non-type; A cross-section of a midbody segment, caudal view B midbody paratergite with setae and an ozopore, lateral view C tegument texture, limbus and setae D midbody leg. - Scale bars: A 0.1 mm; D 0.05 mm; B 0.02 mm; C 0.01 mm.
Figure 35.
Martensodesmus spiniger
sp. n., ♂ paratype; A right gonopod, ventral view B, C left gonopod, frontodorsal and subdorsal views, respectively. - Scale bar: 0.1 mm.