Oxidus gracilis ( C.L. Koch, 1847 )

Anh D. Nguyen, Zoltán Korsós, Kuem-Hee Jang & Ui-Wook Hwang, 2017, A revision and phylogenetic analysis of the millipede genus Oxidus Cook, 1911 (Polydesmida, Paradoxosomatidae), European Journal of Taxonomy 293, pp. 1-22 : 6-8

Oxidus gracilis ( C.L. Koch, 1847)

Figs 1–2

Fontaria gracilis C.L. Koch, 1847: 142 .

Fontaria gracilis – Koch C.L. 1863: 51, pl. 85, fg. 173.

Oxidus gracilis – Cook 1911: 628. — Jeekel 1963a: 20; Jeekel 1968: 71. — Nguyen & Sierwald 2013: 1292.

Orthomorpha (Kalorthomorpha) gracilis – Attems 1914: 196.

Material examined

JAPAN: 1 ♂, Central Ryukyus, Okinawa-jima Island, Onna-son, Onna, Camp Hansen training area at Gate 28, 20 m a.s.l., 26°29′44″ N, 127°51′36″ E, 31 Aug. 2010, leg. Z. Korsós (IEBR-501); 3 ♂♂, 3 ♀♀, Central Ryukyus, Okinawa-jima, Okuni rindo forest trail, 26°43′55″ N, 128°12′30″ E, 25 Sep. 2012, leg. Z. Korsós (IEBR-H471); 3 ♂♂, 3 ♀♀, Central Ryukyus, Okinawa-jima, Nago city, Makiya, Makiya-notaki waterfall, 26°37′44″ N, 128°02′42″ E, 100 m, 2 Sep. 2012, leg. Z. Korsós (IEBR-H466).

USA: 13 ♂♂, 5 ♀♀, Florida, Columbia, Co., Ichetucknee St., PK, 3 May 1981 (IEBR-USA).

SOUTH KOREA: 4 ♀♀ (IPE-Myr 001), 1 ♂, Geoje Island, 8 Aug. 1970, leg. K.Y. Paik (IPE-Myr 003); 7 ♀♀, Geoje Island, 7 Aug. 1970, leg. K.Y. Paik (IPE-Myr 002); 1 ♂, Jeollanam-do, Gwangju, 6 Oct. 1962, leg. S.C.Kim (IPE-Myr 004); 4 ♂♂, Songnisan National Park, 24 Jul. 1961, leg. G.Y. Baek (IPE- Myr 005); 1 ♂, Gyeongsangbuk-do, Cheongsong-gun, Hyeondong-myeon, Wolmae-ri, 18 Jul. 1966, leg. Kim Jae Ho (IPE-Myr 007); 3 ♂♂, 3 ♀♀, leg. K.Y. Paik (IPE-Myr 009).

TAIWAN: 1 ♂, Miaoli County, Taian Township, Kuanwu, SE ridge of Mt. Yemagan, 24°31′13″ N, 121°07′11″ E, 1925 m, secondary mixed forest, 20 Oct. 2009, leg. L. Dányi and E. Lazányi (HNHM-T09-51); 1 ♂, 1 ♀, Taichung County, Heping Township, Dasyueshan Forest Recreation Areas, 10 Shsuehshan Rd., 7 May 2003, leg. Shining Wu (IEBR-Myr 550); 3 ♂♂, 1 ♀, Miaoli County, Taian Township, Dalu Forest Rf., West Feeder, Guanwu lodge, 12 Aug. 2002, leg. Chen Chao Chun (IEBR- Myr 551).

Diagnosis

This species differs from its congeners in the gonopod femorite being strongly expanded distally, not cylindrically slender; postfemoral lamina l rectangular; spine z pointed tuberculiform; process h lamellar, slightly suberect, but bent upwards from midpart, serrated at distolateral part; both bases of process h and spine z clearly separated; mesal lobule of solenophore very well-developed, lamella-shaped, distinctly separated from tip of solenophore; tips of both mesal lobule and solenophore circularly emarginated.

DNA

For Oxidus gracilis , DNA data was collected for three genes (mitochondrial COI gene, nuclear 18S and 28S rRNA genes), but there is no data from the mitochondrial 16S rRNA. In this study, two fragments of COI and 16S were sequenced and deposited in GenBank (see Table 1).

Distribution

The species is widely distributed over the world, mainly in warm temperate regions, and associated with disturbed habitats ( Nguyen & Sierwald 2013). Island records for the Ryukyu Archipelago, Japan: Tanega-shima, Nakano-shima, Akuseki-jima, Takara-jima, Amami-O-shima, Okinoerabu-shima, Yoron-to, Okinawa-jima, Senaga-jima, Miyagi-jima, Iheya-jima, Izena-jima, Ie-jima, Kudaka-jima, Tsuken-jima, Yakabi-jima, Tokashiki-jima, Tonaki-jima, Aguni-jima, Kume-jima, Miyako-jima, Ikemajima, Ishigaki-jima, Iriomote-jima, Kohama-jima, Taketomi-jima, Aragusuku-jima, Hateruma-jima, Yonaguni-jima, Minami-Daito-jima.

Figures

Fig. 1. Oxidus gracilis (C. L. Koch, 1847) from Okinawa Island, Japan. A. Entire body, length ca 23 mm. B – C. Segments 8 – 9 – 10. B. ♂. C. ♀. Scale bars = 1 mm. (photos by Z. Korsós)

Fig. 2. Left gonopod of Oxidus gracilis (C. L. Koch, 1847), sample IEBR-USA. A. Lateral view. B. Mesal view. Scale bars = 100 µm.