Species Divers. 20(1): 13-17
Total Page:16
File Type:pdf, Size:1020Kb
Species Diversity 20: 13–17 25 May 2015 DOI: 10.12782/sd.20.1.013 Records of Two Manefishes, Platyberyx andriashevi and P. rhyton (Teleostei: Perciformes: Caristiidae), from off the Ogasawara Islands, Japan Makoto Okamoto1,3 and Duane E. Stevenson2 1 Seikai National Fisheries Research Institute, 1551–8 Taira-machi, Nagasaki 851–2213, Japan E-mail: [email protected] 2 National Marine Fisheries Service, Alaska Fisheries Science Center, Resource Assessment and Conservation Engineering Division, 7600 Sand Point Way NE, Seattle, Washington 98115, USA E-mail: [email protected] 3 Corresponding author (Received 31 October 2014; Accepted 3 March 2015) We examined four specimens of caristiids from the Ogasawara Islands, southern Japan, and identified two species of the genus Platyberyx: P. andriashevi (Kukuev, Parin and Trunov, 2012) and P. rhyton Stevenson and Kenaley, 2013. The three specimens of P. andriashevi represent the first records of this species in Japan. We propose a new Japanese name for the spe- cies and present morphological data on these recently collected specimens. Platyberyx rhyton was previously known from only two specimens from off northeastern Japan. We provide morphological data for the third recorded specimen of this species and present a key to the five species of Caristiidae currently known from Japan. Key Words: manefish, Caristiidae, Platyberyx, distribution, western North Pacific, new record. Introduction Materials and Methods The caristiid genus Platyberyx Zugmayer, 1911 is known Methods of counting and measuring follow Hubbs and from all tropical, subtropical, and temperate oceans and Lagler (1958), except that body depth is measured through includes at least six species (Stevenson and Kenaley 2013): the dorsal insertion of the pectoral fin. Counts of verte- Platyberyx andriashevi (Kukuev, Parin, and Trunov, 2012); P. brae and dorsal- and anal-fin rays were taken from radio- mauli (Kukuev, Parin, and Trunov, 2012); P. opalescens Zug- graphs. The last two soft rays of the dorsal and anal fins mayer, 1911; P. paucus Stevenson and Kenaley, 2013; P. pi - are counted as single rays, each pair being associated with etschi Stevenson and Kenaley, 2013; and P. rhyton Stevenson a single pterygiophore. Standard length and head length are and Kenaley, 2013. Platyberyx is distinguished from all other expressed as SL and HL, respectively. The diagnoses of P. caristiid genera by the presence of a lateral line with large andriashevi and P. rhyton given here are based on the pres- scales (Stevenson and Kenaley 2013). ent specimens, as well as those of Stevenson and Kenaley Recently, Tatsuta et al. (2014) published a report on me- (2013) and Okamoto et al. (2014). The specimens examined sopelagic fishes collected by beam trawl around the Oga- in the present study are deposited in the Hokkaido Univer- sawara Islands. They identified two species of caristiid sity Museum in Hakodate, Japan (HUMZ), the Kagoshima fishes, Caristius macropus (Bellotti, 1903) and Paracaristius University Museum in Kagoshima, Japan (KAUM), and the maderensis (Maul, 1949), and provided brief descriptions University of Washington Fish Collection (UW) in Seattle, with photos of these species. Although the genus Caristius, Washington, USA. as defined by Stevenson and Kenaley (2013), has no lateral line, the specimen of supposed C. macropus in Tatsuta et al. Platyberyx andriashevi (Kukuev, Parin, and Trunov, 2012) (2014: fig. 98) has a clearly visible lateral line represented [New Japanese name: Irojiro-yaegisu] by enlarged tubular scales. To resolve this discrepancy, we (Fig. 1A) re-examined the four specimens originally identified as C. macropus and re-identified them as two species of the genus Caristius andriashevi Kukuev, Parin, and Trunov, 2012: 195 Platyberyx: P. andriashevi (three specimens) and P. rhyton (type locality: South Atlantic and western North Atlan- (a single specimen). These specimens represent the first re- tic). cords of P. andriashevi from Japan and only the third known Platyberyx andriashevi: Stevenson and Kenaley 2013: 418 specimen of P. rhyton. (Pacific, Atlantic, and Indian oceans). Caristius macropus (not Bellotti, 1903): Tatsuta et al. 2014: 52 (Ogasawara Islands, Japan, in part). © 2015 The Japanese Society of Systematic Zoology 14 M. Okamoto and D. E. Stevenson Fig. 1. Two species of the genus Platyberyx from off the Oga sawara Islands, Japan. A, Platyberyx andriashevi, HUMZ 211647, 180 mm SL; B, Platyberyx rhyton, HUMZ 211061, 145 mm SL. Material examined. 3 specimens: HUMZ 211060, bladelike ventral procurrent caudal rays, and an anteriorly 152 mm SL, off the Ogasawara Islands, Japan, western North directed hook-like process on the third posteriormost ven- Pacific, 27°37.5′N, 141°35.1′E–27°10.0′N, 141°57.3′E, tral procurrent caudal ray; body color beige. 300–2000 m depth, beam trawl, 14–15 December 2010, T/S Remarks. Although P. andriashevi has been reported Oshoro-maru; HUMZ 211062, approximately 140 mm SL throughout the Pacific and Atlantic oceans, as well as in the (caudal region damaged), data same as for HUMZ 211060; Indian Ocean, the present specimens represent the first re- HUMZ 211647, 180 mm SL, off the Ogasawara Islands, cord of the species from Japan, western North Pacific (Fig. Japan, western North Pacific, 26°46.6′N, 147°57.9′E, 570– 2). We propose a new Japanese name, Irojiro-yaegisu (“Iro- 730 m depth, beam trawl, 15 December 2010, T/S Oshoro- jiro” meaning a fair complexion) for P. andriashevi, reflect- maru. ing the appearance of the species, which is generally less Diagnosis. A species of Platyberyx with the following densely pigmented than congeners. combination of characters: dorsal-fin rays 31–35; anal-fin The current specimens closely match the morphological rays 20–22; vertebrae 36–39; presence of laterally flattened, descriptions of Kukuev et al. (2012) and Stevenson and Ke- Platyberyx andriashevi from the Ogasawara Islands 15 Fig. 2. Distributional records of Platyberyx andriashevi [open square = present study; solid squares = Stevenson and Kenaley (2013)] and Platyberyx rhyton [open circle = present study; solid circles = Stevenson and Kenaley (2013) and Okamoto et al. (2014)]. naley (2013), and their meristics and morphometrics are all horo-maru. similar to those of previously reported specimens (Table 1). Diagnosis. A species of Platyberyx with the follow- The only slight differences are that the pectoral-fin ray count ing combination of characters: dorsal-fin rays 30–31; anal- in one specimen (HUMZ 211062) is slightly higher than the fin rays 18–19; pectoral-fin rays 17–18; vertebrae 33–34; previously known range for the species (19/20 vs. 17–18) ventral caudal spur absent; prepectoral length 31.4–34.0% and the lower jaw length in all three specimens is slightly SL; dorsal-fin base 76.0–79.0% SL; upper jaw extending ap- shorter than in previously reported specimens. However, proximately to posterior margin of orbit; gill rakers narrow, this range of variation in both meristics and morphometrics bladelike, with few bristles concentrated near tip; jaw teeth is typical among caristiids (see Stevenson and Kenaley 2013: arranged in single row; dorsal pharyngeal papillae saclike, table 1). multifid papillae absent inside mouth; body color brown. The family Caristiidae in Japanese waters includes P. an - Remarks. Platyberyx rhyton was described based on driashevi and four other species (Fujii 1984; Stevenson and a single specimen from northeastern Japan off Iwate Pre- Kenaley 2011; Hatooka 2013; Stevenson and Kenaley 2013; fecture at 650–677 m depth (Stevenson and Kenaley 2013). Okamoto et al. 2014): Caristius macropus; Paracaristius Subsequently, a second specimen was collected near the maderensis; Paracaristius nudarcus Stevenson and Kenaley, type locality at 0–750 m (Okamoto et al. 2014). The present 2011; and Platyberyx rhyton. A key to the species of Caristi- specimen represents the third known specimen of the spe- idae currently known from Japan, modified from the key of cies and the first record from southern Japan (Fig. 2). Okamoto et al. (2014), is provided below. The present specimen matches the morphological de- scriptions given by Stevenson and Kenaley (2013) and Oka- Platyberyx rhyton Stevenson and Kenaley, 2013 moto et al. (2014), and its meristics and morphometrics are [Japanese name: Sanriku-yaegisu] (Fig. 1B) similar to those of the previous specimens (Table 1). Counts of anal-fin rays (19 in the present study vs 18 in Stevenson Platyberyx rhyton Stevenson and Kenaley, 2013: 424 (type and Kenaley 2013 and Okamoto et al. 2014) and pectoral- locality: off Iwate Prefecture, northeastern Japan); Oka- fin rays (17 vs 18) are slightly different, but well within the moto et al. 2014: 26 (off northeastern Japan). typical range of meristic variation in caristiids (see Steven- Caristius macropus (not Bellotti, 1903): Tatsuta et al. 2014: son and Kenaley 2013: table 1). Vomerine and palatine tooth 52 (Ogasawara Islands, Japan, in part). counts are slightly higher than those previously reported, but the present specimen is in relatively good condition, so unlike previously reported specimens (Okamoto et al. Material examined. 1 specimen: HUMZ 211061, 2014), it is unlikely to have lost any teeth in preservation. 145 mm SL, off the Ogasawara Islands, Japan, western North The morphometrics of the present specimen do not differ Pacific, 27°37.5′N, 141°35.1′E–27°10.0′N, 141°57.3′E, 300– notably from those of previous specimens. 2000 m depth, beam trawl, 14–15 December 2010, T/S Os-