Nemateleotris decora Randall & Allen, 1973

Tea, Yi-Kai & Larson, Helen K., 2023, Synopsis of the ptereleotrine goby genus Nemateleotris, with description of a new species from the western and central Pacific Ocean (Teleostei: Gobiidae), Raffles Bulletin of Zoology 71, pp. 248-266 : 254

Nemateleotris decora Randall & Allen, 1973

Decorated Dartfish Other names: Elegant Firefish; Purple Firefish; Purple Firegoby ( Figs. 2B, D, F, 8E, F , 9C , 10B 1–B 2, 11; Table 2)

Nemateleotris decora Randall & Allen, 1973: 361 , fig. 5 (holotype BPBM 9533, Augulupelu Reef, Palau); Fourmanoir & Laboute, 1976: 142 (checklist; New Caledonia); Masuda et al., 1984: 245 (checklist; Japanese archipelago); Myers, 1988 (checklist; Marianas Islands); Myers, 1989: pl. 118B (field guide, aquarium photograph of specimen from Micronesia); Kuiter & Debelius, 1994: 267 (field guide, underwater photograph from Southeast Asia). Randall et al., 1997: 415 (field guide, Great Barrier Reef & Coral Sea); Myers, 1999: pl. 164F (field guide, underwater photograph from Micronesia); Allen et al., 2003: 282 (field guide; underwater photograph); Randall, 2005: 564 (field guide, underwater photograph from Halmahera); Randall et al., 2005 (checklist; Marshall Islands); Allen et al., 2007: 222 (underwater photograph from Christmas Island); Fricke et al., 2009 (checklist; Réunion Island); Fricke et al., 2011b: fig. 463 (checklist; Vanuatu); Fricke et al., 2011a (checklist; New Caledonia); Allen & Erdmann, 2012: vol. 3, 993 (underwater photographs from Papua New Guinea and Andaman Islands); Randall & Connell, 2013: fig. 4 (underwater photograph from Kwajalein Atoll, Marshall Islands); Randall & Connell, 2013: figs. 5–8 (photograph of holotype and underwater photographs from Halmahera, Raja Ampat, and Bali); Allen et al., 2015: 286 (field guide, underwater photograph); Rosenstein, 2019: 271 (field guide; underwater photograph from Fiji).

Nemateleotris exquisita Randall & Connell, 2013: 25 (type locality: Mauritius); Tea et al., 2020a (checklist; Réunion Island).

Diagnosis. Dorsal-fin rays VI, I,27–33; anal-fin rays I,28–32; pectoral-fin rays 19–21; pelvic-fin rays I,5; segmented caudal-fin rays 17; upper procurrent caudal-fin rays 10–13; lower procurrent caudal-fin rays 10–12; total caudal-fin rays 37–42; gill rakers 5–6 + 14–18 = 19–24; caudal fin weakly emarginate, tips of upper and lower lobes sometimes pronounced; pelvic fins red-tipped in life; anterior body pale grey to yellowish in life, dusky purple posteriorly.

Remarks. Nemateleotris decora occurs throughout the Indian Ocean, including the Red Sea. In the western Pacific it occurs from the Ryukyu Islands south to the Great Barrier Reef, New Caledonia, and Melanesia. It also occurs in Palau (type locality) east to the Caroline Islands and the Marshall Islands ( Randall et al., 2005). The Indian Ocean and Red Sea population was previously regarded as a separate species, N. exquisita . The synonymy and relationship of N. exquisita and N. decora is discussed below.

Etymology. From the Latin meaning elegant and beautiful.

Figures

Fig. 8. Species of Nemateleotris and their putative hybrids. A, N. helfrichi, underwater photograph from Rarotonga, Cook Islands; B, N. lavandula, new species, underwater photograph from Siaes Tunnel, Palau; C, head profiles of N. helfrichi (left) and N. lavandula, new species, (right) showing difference in colouration of the head and maxilla; D, N. magnifica, underwater photograph from Bali; E–F, N. decora, showing variability in colouration of the anterior body, underwater photograph from Fiji and the Maldives (the latter = N. exquisita sensu Randall & Connell, 2013) respectively; G, putative N. magnifica × N. decora, underwater photograph from Izu Peninsula, Japan; H, putative N. magnifica × N. lavandula, new species, underwater photograph from Okinoerabu Island, Japan. Photographs by: A, P.Jaletzky; B, R. Spangler; C, Y.K. Tea; D, V. Chalias; E, J. Heard; F, M. Harada; G, Y. Yamada; H, K. Uehara.

Fig. 9. Frontal head profiles of selected species of Nemateleotris. A, N. helfrichi, aquarium specimen from Cook Islands; B, N. lavandula, new species, ZRC 62990, paratype in life, specimen from Kwajalein Atoll, Marshall Islands, Micronesia; C, N. decora, underwater photograph from Bali, Indonesia; D, N. magnifica, underwater photograph from Bali, Indonesia. Photographs by: A, B-box Aquarium, Japan; B, H.H. Tan; C–D, V. Chalias.

Fig. 10. Species of Nemateleotris in life (A1–E1) and preserved colouration (A2–E2). A1, N. magnifica, aquarium specimen from Indonesia, specimen not retained; A2, N. magnifica, ZRC 47157, 36.6 mm SL, Bali, Indonesia; B1, N. decora, aquarium specimen from Indonesia, specimen not retained; B2, N. decora, ZRC 47158, 51.3 mm SL, Bali, Indonesia; C1, N. helfrichi, aquarium specimen from the Cook Islands, specimen not retained; C2, N. helfrichi, ZRC 61811, 62.4 mm SL, Cook Islands; E1–E2, N. lavandula, new species, ZRC 62990, paratype, 38.9 mm SL, aquarium specimen from Kwajalein Atoll, Marshall Islands, Micronesia. Photographs by: A1–B1, E2, Y.K. Tea, C1, S.W. Michael; E1, H.H. Tan; A2–C2, K. Lim.

Fig. 1. Laterosensory pores and neuromasts based on holotype of Nemateleotris helfrichi (BPBM 11595). A, lateral view; B, dorsal view. Letter codes (in blue) for laterosensory pores follow Akihito et al. (1984). ANP, anterior nasal pore; PNP, posterior nasal pore; AOC, anterior oculoscapular canal; PC, preopercular canal; FDF, first dorsal fin. Arrowhead indicates position where gill membranes are attached to the isthmus.