Epigonus lifouensis Okamoto and Motomura 2013
Creators: name: Okamoto, Makoto
Publisher: name: Zenodo
Year: 2018
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Perciformes
Epigonidae
Epigonus
Epigonus lifouensis

description: <i>Epigonus lifouensis</i> Okamoto and Motomura, 2013 (Fig. 1; Table 1) <i>Epigonus denticulatus</i> (not of Dieuzeide): Inada and Wudianto 2006: 32 (photograph, off Sumatra, Indonesia). <i>Epigonus lifouensis</i> Okamoto and Motomura, 2013: 302, fig. 1 (original description, type locality: 21°40′59″S, 167°31′59″E, south of Lifou Island, Loyalty Islands, New Caledonia, western Pacific); Okamoto <i>et al</i> <i>.</i> 2018: (South China Sea, Taiwan). <b>Material examined.</b> HUMZ 190770 (137.4 mm SL, male)–190771 (131.5 mm SL, male), 05°29′11″N, 94°01′47″E – 05°27′49″N, 94°01′52″E, off Sumatra, Indonesia, 347–361 m depth, 13 October 2004; HUMZ 191536–191545, 10 specimens, 05°46′52″N, 102°41′25″E – 05°46′02″N, 102°39′53″E, off Sumatra, Indonesia, 546–639 m depth, 26 September 2004; (HUMZ 191536, 170.1 mm SL, male; HUMZ 191537, 151.7 mm SL, male; HUMZ 191538, 162.8 mm SL, female; HUMZ 191539, 150.4 mm SL, male; HUMZ 191540, 143.2 mm SL, male; HUMZ 191541, 153.8 mm SL, male; HUMZ 191542, 180.7 mm SL, female; HUMZ 191543, 172.3 mm SL, male; HUMZ 191544, 156.7 mm SL, male; HUMZ 191545, 163.1 mm SL, male). <b>Diagnosis.</b> A species of <i>Epigonus</i> with the following combination of characters: dorsal-fin rays VII-I, 10; pectoral-fin rays 18–19; total gill rakers 24–28; vertebrae 10+15; pyloric caeca 10–13; pored lateral-line scales 47–49+4–5; body depth 17.0–20.1% SL; opercular spine absent; maxillary mustache-like processes absent; tongue toothless; ribs present on last abdominal vertebra; tubercle absent on inner symphysis of lower jaw; eye elliptical; and posterior half of oral cavity and tongue black. <b>Distribution.</b> Known from New Caledonia (Okamoto and Motomura 2013), South China Sea (Okamoto <i>et al.</i> 2018), and Indonesia (present study; Fig. 2), at depths of 347– 639 m. <b>Remarks.</b> In the faunal study of demersal fishes in Indonesia (Inada and Wudianto 2006), the present specimens from off Sumatra were identified as “ <i>Epigonus denticulatus</i> Dieuzeide 1950 ”. However, I re-examined the specimens and identified them as <i>E. lifouensis</i> in the present study (Fig. 1). <i>Epigonus lifouensis</i> can be distinguished from <i>E. denticulatus</i> by having fewer gill rakers (24–28 <i>vs.</i> 28–34 in <i>E. denticulatus</i>) and a black tongue and oral cavity (<i>vs.</i> tan; Dieuzeide 1950; Mochizuki 1982, 1990; Abramov 1992; Okamoto and Gon 2018). In the eastern Indian Ocean, <i>E. denticulatus</i> has been reported from the south of the Great Australian Bight (Abramov 1992; Kamysheva 1985), but not from the north eastern Indian Ocean, to date. <i>Epigonus lifouensis</i> was originally described based on two specimens from the south of Lifou Island, Loyalty Islands, New Caledonia (Okamoto and Motomura 2013). Later, a single specimen of the species was collected from a seamount nearby the Macclesfield Bank, South China Sea (Okamoto <i>et al.</i> 2018). The present specimens represent the first record of the species from the eastern Indian Ocean (Fig. 2). <i>Epigonus lifouensis</i> belongs to the <i>E. pandionis</i> group of Okamoto and Motomura (2013) defined as lacking an opercular spine, more than 45 pored lateral-line scales to the end of the hypural and dorsal-fin rays VII-I, 10. The species group comprises 9 species, including <i>E. lifouensis</i>: <i>E. cavaticus</i> Ida <i>et al.</i>, 2007; <i>E. denticulatus</i> Dieuzeide, 1950; <i>E. elongatus</i> Parin and Abramov, 1986; <i>E. fragilis</i> (Jordan and Jordan, 1922); <i>E. marisrubri</i> Krupp <i>et al.</i>, 2009; <i>E. pandionis</i> (Goode and Bean, 1881); <i>E. parini</i> Abramov, 1987; and <i>E. tuberculatus</i> Okamoto and Motomura, 2013. Characters of the present Indonesian specimens agree with the characteristics of the two types and another specimen from the western Pacific of <i>E. lifouensis</i> reported in previous studies, with the exception of the gill rakers for which the Indonesian specimens had 26–28 (<i>vs.</i> 24–25 in Okamoto and Motomura 2013; Okamoto <i>et al.</i> 2018). Although the gill raker counts of <i>E. lifouensis</i> reported in previous studies are based on a small number of the specimens (totall 3 specimens), I regard the difference as an intraspecific variation in the populations between the western Pacific and eastern Indian Oceans, with no overlap.
description: Published as part of <i>Okamoto, Makoto, 2018, First Records of Two Deepwater Cardinalfishes (Perciformes: Epigonidae), Epigonus lifouensis and E. pectinifer, from Indonesia, Eastern Indian Ocean, pp. 243-248 in Species Diversity 23</i> on pages 243-245, DOI: 10.12782/specdiv.23.243, http://zenodo.org/record/5738070
description: {"references": ["Okamoto, M. and Motomura, H. 2013. Two new species of deepwater cardinalfish from the Indo-Pacific, with a definition of the Epigonus pandionis group (Perciformes: Epigonidae). Ichthyological Research 60: 301 - 311.", "Inada, T. and Wudianto, Ir. (Eds.) 2006. The Japan-Indonesia Deep Sea Fishery Resources Joint Exploration Project (Photo Album). Overseas Fishery Cooperation Foundation, Japan and Indonesia, 71 pp.", "Dieuzeide, R. 1950. Sur un Epigonus nouveau de la Mediterranee (Epigonus denticulatus nov. sp.). Bulletin des Travaux Publies par la Station d'Aquiculuture et de Peche de Castiglione 2: 87 - 105.", "Mochizuki, K. 1982. Apogonidae. Pp. 226 - 227, 376 - 377. In: Okamura, O., Amaoka, K., and Mitani, F. (Eds) Fishes of the Kyushu-Palau Ridge and Tosa Bay. Japan Fisheries Resource Conservation Association, Tokyo.", "Mochizuki, K. 1990. Apogonidae. Pp. 258 - 263. In: Amaoka, K., Matsuura, K., Inada, T., Takeda, M., Hatanaka, H., and Okada, K. (Eds) Fishes Collected by the R / V \" Shinkai Maru \" around New Zealand. Japan Marine Fishery Resources Research Center, Tokyo.", "Abramov, A. A. 1992. Species composition and distribution of Epigonus (Epigonidae) in the world ocean. Journal of Ichthyology 32 (5): 94 - 108.", "Okamoto, M. and Gon, O. 2018. A review of the deeepwater cardinalfish genus Epigonus (Perciformes: Epigonidae) of the Western Indian Ocean, with description of two new species. Zootaxa 4382: 261 - 291.", "Kamysheva, T. P. 1985. Comparative morphometric characters of Epigonus denticulatus Dieuzeide (Perciformes, Apogonidae) from the Gerakl and Hawaiian ranges. Journal of Ichthyology 25 (6): 36 - 43.", "Parin, N. V. and Abramov, A. A. 1986. Materials for a revision of the genus Epigonus Rafinesque (Perciformes, Epigonidae): species from the submarine ridges of the southern East Pacific and preliminary review of the \" Epigonus robustus species-group \". Trudy Instituta Okeanologii im. P. P. Shirshova 121: 173 - 194. [In Russian]"]}