Owstonia totomiensis Tanak

Smith-Vaniz, William F. & Johnson, David, 2016, Hidden diversity in deep-water bandfishes: review of Owstonia with descriptions of twenty-one new species (Teleostei: Cepolidae: Owstoniinae), Zootaxa 4187 (1), pp. 1-103 : 91-93

Owstonia totomiensis Tanak a

( Figures 81–83 )

Owstonia totomiensis Tanaka, 1908:47 , pl. 3, fig. 1 (original description; coast of Totomi Prov., Japan); Shiino, 1972:116 (common name Bottom jawfish); Machida in Masuda et al., 1984:201, Pl. 192-E (brief description, color photograph) Shin et al., 1993:436, pl. 137–6 (brief description, color photograph); Shinohara and Matsuura, 1997:306 (listed in checklist, Suruga Bay; Japanese name Soko-amadai); Nakabo, 2002:914 (diagnosis, in pictorial key); Ikeda and Nakabo, 2015:441, pl. 167, color figs. 1–3 (description).

Material examined. 5 specimens, 134‒305 mm SL all from Japan: FMNH 55424 (306), holotype of Owstonia totomiensis, Totomi, Honda, D. S . Jordan, 10 Feb. 1906; CAS 133936 (1, 134) , Kochi Pref., Kochi, T. Kamohara, 1937; MCZ 29852 (1, 305), Sagami Bay , Alan Owston purchase, 23 Sep. 1908 ; NSMT-P 7151 (1, 223), Honshu, Suruga Bay , Sep. 1968; NSMT-P 77978 (1, 285), Shikoku, Kochi Pref. , Kochi, Mimase fishing port, Y. Yamanoue, 6 Sep. 1999 .

Diagnosis. A species of Owstonia with LL pattern 3; naked nape and cheeks; oblique body scale rows in midlateral series 50‒60; caudal peducle depth 2.3‒3.0 in its length.

Description. A species of Owstonia with LL pattern 3, consisting of a lateral line that does not contact posttemporal sensory canal near anterodorsal margin of gill opening (although a diagonal row of 2–4 scales is present at its margin), and instead continues posteriorly just below dorsal-fin base and anteriorly where it makes a complete loop across nape; lateral line ends below dorsal-fin soft rays 19‒20. Dorsal fin III, 20–21; anal fin I, 13– 14; pectoral fin 20–21; gill rakers 14–18 + 27–28 = 42–46. Vertebrae: precaudal 11, caudal 17, total 28; anal-fin pterygiophores anterior to 1st haemal spine 2. Oblique body scale rows in mid-lateral series about 50–60; nape and cheeks naked (except 1 or 2 embedded scales below orbit in two specimens). Lower limb margin of preopercle with about 9–11 short nubby spines. Papillae in slight depression behind tip of premaxillary ascending processes in a nearly straight posterior row of about 8−10 small papillae flanked anteriorly by irregular cluster of 18−20 papillae that are difficult to clearly discern due to the rugose skin folds ( Fig. 14 F). Teeth in outer row of each premaxilla 14–21 with short blunt tips; 0–2 much smaller inner teeth anteriorly. Teeth in lateral row of each dentary 7−15, including 1−4 at anterior end that continue behind symphyseal teeth; symphyseal teeth 4–7, short and spike-like, and with 1−2 small inner teeth anteriorly. Pelvic fin probably sexually dimorphic, depressed fin extends posteriorly slightly behind anus in the 223 mm SL gravid female and from anal-fin origin to 3rd soft ray in three other unsexed specimens (134‒306 mm SL). Caudal fin lanceolate. Caudal fin 1.6‒2.2 times in SL; head 3.4‒3.9 times in SL; body depth at anal-fin origin 3.5‒4.2 times in SL. Caudal peduncle depth 1.3−1.7 times in its length.

Color pattern in alcohol: Adults with anterior part of dorsal fin uniformly pale; membrane connecting maxilla and premaxilla with prominent black stripe extending to near anterior end of premaxilla, and inner membrane covering posterior part of dentary also black. In fresh specimens, dorsal fin with red distal stripe that is much wider on spinous part of fin and bordered by narrow white stripe; upper half of caudal fin with very narrow red margin; remainder of these two fins and all others pink; body and head red dorsally, gradually changing to pink and white ventrally; iris red. The prominent red spot on the maxilla of specimen BSKU 93693 ( Fig. 81 ) is probably an atypical variation.

Proportions of 4 specimens 134‒306 mm SL, as percentages of SL: predorsal length 21.5–28.0; preanal length 53.6–58.5; dorsal-fin base 60.0–65.5; anal-fin base 29.0–32.0; caudal peduncle length 15.7–18.9; caudal peduncle depth 10.6–11.8; pelvic-fin length 27.5–30.9; caudal-fin length 45.7–61.4; body depth at anal-fin origin 23.9–28.3; head length 25.8–29.3; upper jaw length 14.0–15.2; upper jaw depth 6.0–7.4; orbit diameter 10.1–11.1. As percentages of head length: upper jaw length 51.9–54.6); orbit diameter 38.0–41.1).

Comparisons. Owstonia nudibucca , the only other species with LL pattern 3 and naked nape and cheeks, differs (characters of O. totomiensis in parentheses), in having horizontal section of lateral line with a short ventral side branch slightly before dorsal-fin origin (vs. no short side branch present), fewer oblique body scale rows in mid-lateral series 38–44 (vs. 50–60), shallower body depth 17.3‒22.9% SL (vs. 23.9–28.3% SL), shallower caudal peduncle depth 2.3‒3.0 (vs. 1.3−1.7) in its length and more total gill rakers 47‒49 (vs. 42–46).

Etymology. A combination of Totomi (former province of Japan) and the Latin suffix ensis (meaning belonging to).

Distribution. ( Fig. 22 ) Known only from Japan where taken in at least 230 m.

Figures

FIGURE 14. Arrangement and relative sizes of papillae in slight depression at tip of ascending premaxillary processes (dorsal view, anterior to right) in selected species of Owstonia: A, O. crassa, MNHN 2002 – 3720; B., O. dispar, MNHN 2002 – 3720; C, O. maccullochi, CSIRO H 5946 – 20; D, O. mundyi, USNM 427880; E, O. sarmiento, NTM S. 11782 – 001; and F, O. totomiensis, NSMT – P 77978.

FIGURE 22. Distributions of selected species of Owstonia based on specimens examined.

FIGURE 81. Owstonia totomiensis, BSKU 93693, 266 mm SL, Japan, off Kochi. Photograph by Hiromitsu Endo.

FIGURE 82. Owstonia totomiensis, KPM-NI 14300, 234 mm SL, Japan, Sagami Bay. Photograph (KPM-NR 57323) by Hiroshi Senou.

FIGURE 83. Owstonia totomiensis, holotype, FMNH 55424, 306 mm SL, Japan. Photograph by Sandra J. Raredon.