Research Article |
Corresponding author: Seong Myeong Yoon ( smyun@chosun.ac.kr ) Academic editor: Alan Myers
© 2018 Tae Won Jung, Charles Oliver Coleman, Ji Hyung Kim, Seong Myeong Yoon.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Jung TW, Coleman CO, Kim JH, Yoon SM (2018) First records of the uristid lysianassoids from Korean waters: redescription of Anonyx abei Takekawa & Ishimaru, 2001 and description of Anonyx exilipes sp. n. (Crustacea, Amphipoda, Uristidae). ZooKeys 733: 99-117. https://doi.org/10.3897/zookeys.733.22021
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The uristid lysianassoids are reported for the first time from Korean waters with a redescription of Anonyx abei Takekawa & Ishimaru, 2001 and the description of Anonyx exilipes sp. n. Anonyx abei is characterized by a distinctively small projection of the posterodistal corner on epimeron 3, different from all species of the Anonyx nugax group which share a constriction at the point of insertion of a distal seta on the inner ramus of uropod 2. Anonyx exilipes sp. n. is included in the Anonyx laticoxae group characterized by the unconstricted inner ramus of uropod 2. This new species is distinguished from other A. laticoxae group species by the longer and more slender carpus and propodus of pereopod 6, and the non-lobate merus of pereopod 7.
Amphipods, Anonyx abei , Anonyx exilipes sp. n., Korea, taxonomy, uristids
The family Uristidae Hurley, 1963 is a widespread and large group of lysianassoid amphipods containing more than 180 species in 25 well-defined genera (
Anonyx Krøyer, 1838 is one of the largest genera of uristids constituted of about 50 species described from the arctic-boreal region (
In spite of the species abundance and wide range of distribution, the taxonomic study on lysianassoids is insufficient in Korea and only eight species have been reported: Aroui minusetosus Jung, Coleman & Yoon, 2017; Lepidepecreum vitjazi Gurjanova, 1962; Orchomenella japonica Gurjanova, 1962; Orchomenella obtusa (GO Sars, 1891); Orchomenella paucisetigera Jung, Yi, Coleman & Yoon, 2017; Orchomenella rugosa Jung, Yi, Coleman & Yoon, 2017; Pseudorchomene boreoplebs Jung, Coleman & Yoon, 2017; and Socarnes tongyeongensis Kim & Hendrycks, 2013 (
Collected specimens were initially fixed in 80% ethyl alcohol in the field and then preserved in 95% ethyl alcohol after sorting in the laboratory. Specimens were stained with lignin pink before dissection. Their appendages were dissected in petri dishes or on excavated microscopic slides filled with glycerol using forceps and needles under a stereomicroscope (Leica M205). They were mounted onto temporary slides using glycerol-ethanol mixed solution or permanent slides using polyvinyl lactophenol solution. For making illustrations, pencil drawings were performed under a light microscope (Leica DMLB) with the aid of a drawing tube. Drawings were scanned, inked digitally and arranged to plates using the methods described in
Korean name: Na-do-gin-pal-yeop-sae-u-gwa, new
Korean name: Na-do-gin-pal-yeop-sae-u-sok, new
Anonyx abei Takekawa & Ishimaru, 2001: 410, figs 6–10.
One male (9.3 mm) and one female (7.8 mm), NIBRV0000807162, Korea: Jeju-do, Beom Is., 33°12.9945N 126°32.215E, depth 66 m, 1 Nov 2016, collected by a light trap.
Gnathopod 1 subchelate; basis weakly setose anteriorly; propodus posterior margin forming weak lobe together palm posterodistally, palm serrated, defined by one pair of elongate robust setae; dactylus with strong protrusion on inner margin. Gnathopod 2 minutely chelate; propodus subquadrate, with nine robust setae anterodistally, posterodistal corner produced distally with two robust setae, palm short, with small cavity; dactylus anchored at middle of distal margin on propodus, inner margin denticulate. Epimeron 2 posteroventral corner a little produced. Uropod 2 inner and outer rami each with a constriction at insertion point of distal elongate seta on dorsal surface.
Head (Fig.
Antenna 1 (Fig.
Antenna 2 (Fig.
Mandible (Fig.
Lower lip (Fig.
Maxilla 1 (Fig.
Maxilla 2 (Fig.
Maxilliped (Fig.
Pereon.Gnathopod 1 (Fig.
Gnathopod 2 (Fig.
Anonyx abei Takekawa & Ishimaru, 2001, male, NIBRV0000807162, 9.3 mm. A gnathopod 2 B gnathopod 2 plam and dactylus C gnathopod 2 carpus to dactylus, medial D coxa 2 E pereopod 3 F pereopod 3 locking seta G pereopod 4 H pereopod 4 locking seta. Scale bars: 0.05 mm (B, F, H), 0.2 mm (A, C–E, G).
Pereopod 3 (Fig.
Pereopod 4 (Fig.
Pereopod 5 (Fig.
Anonyx abei Takekawa & Ishimaru, 2001, male, NIBRV0000807162, 9.3 mm. A pereopod 5 B pereopod 6 C pereopod 7 D pereopod 7 carpus to dactylus E pleonal epimera 1–3, lateral F uropod 1 G uropod 2 H uropod 2 outer ramus I uropod 2 inner ramus J uropod 3 K telson. Scale bars: 0.2mm (A-D, F–K), 0.5 mm (E).
Pereopod 6 (Fig.
Pereopod 7 (Fig.
Pleon.Epimeron 1 weakly produced anteroventrally, rounded posteroventrally. Epimeron 2 larger than epimeron 1, also produced anteroventrally, slightly convex ventrally, posteroventral corner a little produced. Epimeron 3 largest, regularly rounded posteroventrally, posteroventral corner produced backwards. Urosomite 1 with deep dorsal depression and distal carina weak (Fig.
Uropod 1 (Fig.
Uropod 2 (Fig.
Uropod 3 (Fig.
Telson (Fig.
The Anonyx nugax group of
Near Daejin Port, Daejin-ri Hyeonnae-myeon Goseong-gun Gangwon-do South Korea. The specimens were collected from fishery nets of this port. According to the statements of fishermen, these nets were brought out within a 5 km radius from Daejin Port and the nets were deployed in about 1–2 km depth (The precise coordinates were uncertain).
Holotype: Male (23.0 mm), NIBRIV0000806537, paratypes: two males and two females (18.5 mm–24.9 mm), NIBRIV0000807160; 11 Mar 2016, by TW Jung.
The composite epithet of the specific name, exilipes, is a combination of the Latin exilis and pes. This name means ‘slender foot’ referring to the slender shapes of pereopods 6 and 7 compared to those of other species of the Anonyx laticoxae group.
Gnathopod 1 basis with setae along entire anterior margin; palm serrated; dactylus without protrusion. Gnathopod 2 propodus half as long as carpus, posterodistal corner produced distally, palm short, with small cavity; dactylus short, apex not exceeding corner of palm. Pereopods 3–4 each propodus with single locking setae posterodistally. Pereopod 6 carpus and propodus elongate, slender. Pereopod 7 merus not lobate. Epimeron 2 posteroventral corner acutely produced backwards. Epimeron 3 regularly rounded posteroventrally, posterior margin produced backwards. Uropod 2 both rami without constrictions. Uropod 3 inner ramus as long as proximal article of outer ramus.
Head (Fig.
Antenna 1 (Fig.
Antenna 2 (Fig.
Lower lip (Fig.
Mandible (Fig.
Maxilla 1 (Fig.
Maxilla 2 (Fig.
Maxilliped (Fig.
Pereon.Gnathopod 1 (Fig.
Gnathopod 2 (Fig.
Pereopod 3 (Fig.
Pereopod 4 (Fig.
Pereopod 5 (Fig.
Pereopod 6 (Fig.
Pereopod 7 (Fig.
Pleon.Epimeron 1 (Fig.
Uropod 1 (Fig.
Uropod 2 (Fig.
Uropod 3 (Fig.
Telson (Fig.
This study was supported by the National Institute of Biological Resources of Korea as a part of the ‘Survey of indigenous biological resources of Korea (