Xystodesmus yamamiensis Masuda, 2001

Korsós, Zoltán & Nakamura, Yasuyuki, 2025, Review of the millipede genus Xystodesmus (Diplopoda, Polydesmida), with seven new species from the southwestern part of Japan, ZooKeys 1231, pp. 191-232 : 191-232

publication ID

https://doi.org/10.3897/zookeys.1231.141443

publication LSID

lsid:zoobank.org:pub:94B32AD5-4D03-4ECA-8B73-DB157E8AAF3E

DOI

https://doi.org/10.5281/zenodo.15013573

persistent identifier

https://treatment.plazi.org/id/167C9B1E-4A2E-5C2D-A1CE-C8878F50C5CE

treatment provided by

ZooKeys by Pensoft

scientific name

Xystodesmus yamamiensis Masuda, 2001
status

 

Xystodesmus yamamiensis Masuda, 2001 View in CoL

Fig. 15 B View Figure 15

Material examined.

Holotype male ( NSMT -My.294 ), and paratype male ( NSMT -My.295 ), Aichi Pref., Chita County, Minamichita Town, Yamami , 5 April 1998, leg. K. Masuda .

Descriptive notes.

The original description and illustrations lack some important details, thus after the re-examination of the holotype, we present here an additional drawing of the male gonopod (Fig. 15 B View Figure 15 ). Coxa stout, as wide as long, with a strong apophyseal process (ca) and a large macroseta (ms). Prefemur and acropodite slightly twisted, prefemoral process (pfp) ~ ¾ of length of acropodite, those of two gonopods crossing each other in situ. Prostatic groove runs along lateral side of acropodite (a) and ends on distal part of lower branch of bifurcated tip.

Remarks.

Interestingly, the gonopods have a general similarity to Riukiaria neptuna ( Pocock, 1895) ( Korsós et al. 2011) , as the end of acropodite is ramified: two branches in X. yamamiensis , three in R. neptuna (see Pocock 1895; Hoffman 1949). However, the body size (19–24 mm) and especially the colour of X. yamamiensis (“ Keels have a red spot in roughly in the middle. ” Masuda 2001: 635) clearly indicate that this is a species of Xystodesmus .

Unidentified Xystodesmus female 1

Fig. 16 G View Figure 16

Material examined. • 6 females, Japan, Central Ryukyus, Okinawa Pref., Okinawa Group, Tokashiki-jima Isl., National Okinawa Youth Fellowship Center , mixed forest, 26°12'40.7"N, 127°21'46.4"E, 200 m, 9–10 April 2010, leg. Z. Korsós (No. 183) ( RUMF) GoogleMaps ; • 2 females, Japan, Central Ryukyus, Okinawa Pref., Okinawa Group, Tokashiki-jima Isl., Tokashiki, Otani forest road , mixed forest, 26°12'45.3"N, 127°21'26.3"E, 18 m, 10 April 2010, leg. Z. Korsós ( HNHM diplo-04552 ) GoogleMaps ; • 2 females, Japan, Central Ryukyus, Okinawa Pref., Okinawa Group, Tokashiki-jima Isl., National Okinawa Youth Fellowship Center , outside the fence, mixed forest, 26°12'44"N, 127°21'50"E, 215 m, 21 October 2010, leg. Z. Korsós (No. 266) ( RUMF) GoogleMaps

Colour of living specimens (Fig. 16 G View Figure 16 ). Body uniformly dark brown, posterior edge of metaterga darker; paranota from 5 th segment onward light, yellowish orange; head brown, antennae, legs, and underside whitish.

Remark. Probably the same species as the one occurring on Aka-jima Isl., i. e., X. keramae sp. nov. (Fig. 16 B View Figure 16 ).

Unidentified Xystodesmus female 2

Fig. 16 H View Figure 16

Material examined. • 1 female, Japan, Central Ryukyus, Amami Group, Tokuno-shima Island, Kametsu, near the pass between Mt. Inokawa-dake and Mt. Hage-dake , 27°45'38.4"N, 128°58'53.7"E, Castanopsis sieboldii forest, 4 February 2012, leg. Y. Nakamura ( HNHM diplo-04553 ) GoogleMaps

Colour of living specimens (Fig. 16 H View Figure 16 ). Body uniformly dark greyish brown, median and posterior part of metaterga darker; all paranota including collum with light, yellowish spots; head and epiproct greyish brown; antennae, legs, and underside whitish.

Remark. Up to now this is the only Xystodesmus specimen from Tokuno-shima Island and probably represent a different species. However, without knowing the male it would be premature to assign it to any category.

Kingdom

Animalia

Phylum

Arthropoda

Class

Diplopoda

Order

Polydesmida

Family

Xystodesmidae

SubFamily

Xystodesminae

Tribe

Xystodesmini

Genus

Xystodesmus