Owstonia sibogae (Weber)

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 : 82-84

Owstonia sibogae (Weber)

( Figures 73 , 74 )

Sphenanthias sibogae Weber, 1913:595 , pl 2, figs. 4 & 4a (original description; Timor Sea, 10°27.9'S, 123°28.7'E, Indonesia; depth 216 m); Weber and de Beaufort, 1932:114, fig. 20 (redescription).

Sphenanthias pectinifer Myers, 1939:19 (original description; off Dumalag Island, Davao Gulf, Mindanao, Philippines, R/V Albatross sta. D.5255; depth 100 fms [183 m]).

Owstonia pectinifer . Gloerfelt-Tarp and Kailola, 1984:229, unnumbered color photograph (brief description); Prokofiev, 2010:408, figs. 1 & 2 ( Sphenanthias synonymized with Owstonia ; O. pectinifer provisionally recognized as a valid species).

Owstonia sibogae . Endo et al., 2016:37 (lectotype designation of Sphenanthias sibogae , ZMA 112.568, 82 mm SL, Timor Sea; comparative material six specimens, 80.5‒122 mm SL).

Material examined. 19 specimens, 82–156 mm SL: Indonesia ZMA 119.382 (2, ca. 93–122), Timor Sea , 10°27.9'S, 123°28.7'E, 216 m, M. Weber, 2 Feb. 1900 ; ANSP 152035 (2, 113 C&S–156) and ANSP 152642 (1, 100), Sumbawa, Saleh Bay , 8°34'S, 117°46'E, 150–280 m, T. Gloerfelt-Tarp, 16 Jul. 1981 ; NMNH 1985–363 (2, 97–98), Sulawesi, 1°57.8'S, 119°15'E, 215 m, P. Fourmanoir, R/ V Corindon II, sta. 271 ; MNHN 1985–356 (1, 58), Sulawesi, 1°57.8'S, 119°15'E, 215m, R/ V Corindon II, sta. 271; BMNH 1986.10 .6.61 (1, 90), Indonesia, no other data . Philippines USNM 93455 (1, 138), holotype of Sphenanthias pectinifer Myers, Mindanao , Davao Bay, E. of Dumalag Island, 7°3'N, 125°39'E, 183 m, R/ V Albatross, sta. D5255, 18 May 1908 ; USNM 93456 (1, 104), Panalangan Point , Talajit Island, between Samar and Masbate, 11°57'N, 124°12'24"E, 250 m, R/ V Albatross sta. D.5396, 15 Mar. 1909 ; CAS 32914 (2, 78–96), Luzon Island, Ragay Gulf, Quezon, Pusago Point , 250 m, J.E. Norton, 11 Nov. 1966 ; CAS 33848 (5, 90–126 C&S), Marinduque Island, SE of Salomagee I., 287–312 m, J. E. Norton, 20 Oct. 1964 . Vietnam USNM 357481 (1, 82), vicinity of Gulf of Tonkin , 15°56'48"N, 109°30'E, 260–315 m, 16 Sep. 1963 .

Diagnosis. A species of Owstonia with LL pattern type 1; dorsal-fin spines IV, 23–24 (rarely 24); anal fin II, 15–17 (typically16); oblique body scale rows in mid-lateral series 27–30; cheek scale rows 3; premaxillary stripe short, extending only about 2/3 length of premaxilla; inner membrane covering posterior part of dentary black.

Description. A species of Owstonia with LL pattern consisting of type 1, a simple lateral line that originates from posttemporal sensory canal near anterodorsal margin of gill opening, curves upward and backward then continues posteriorly just below dorsal-fin base to soft rays 19‒23. Dorsal fin IV, 23–24 (rarely 24); anal fin II, 15– 17 (typically16); pectoral fin 18–20; gill rakers 14–18 + 27–32 = 41–48. Vertebrae: precaudal 12, caudal 17, total 29; anal-fin pterygiophores anterior to 1st haemal spine 4. Oblique body scale rows in mid-lateral series about 27– 30; nape scaly and cheek scale rows 3 ( Fig. 12 I). Lower limb margin of preopercle with 8–14 strong spines ( Fig. 8 I). Papillae in slight depression behind tip of premaxillary ascending processes 4, arranged in 2 almost equally spaced pairs. Teeth in outer row of each premaxilla 29‒41; no inner teeth anteriorly. Teeth in lateral row of each dentary 15‒26; symphyseal teeth 5‒6 short and peg-like, and with 1–4 inner teeth anteriorly. Pelvic fin probably sexually dimorphic, depressed pelvic fin extending only to anus, to anal-fin origin (most specimens) or to soft ray 4. Caudal fin lanceolate. In 9 specimens, 90‒156 mm SL, caudal fin 1.5‒2.2 times in SL; head 3.8‒5.2 times in SL; body depth at anal-fin origin 3.9‒6.4 times in SL.

Color pattern in alcohol: Adults with dorsal fin uniformly pale; membrane connecting maxilla and premaxilla with prominent dark stripe that extends only about 1/2 length of premaxilla ( Fig. 15 C), and inner membrane covering posterior part of dentary also black. Gloerfelt-Tarp and Kailola (1984) recorded the life coloration as "body rosy with areas of pale yellow, maxilla, side of head and pectoral base iridescent; premaxillary groove black, fins greenish yellow, dorsal and anal fins iridescent violet."

Proportions of 10 specimens 82‒156 mm SL mm SL, as percentages of SL: predorsal length 19.7‒25.0; preanal length 45.4‒50.9; dorsal-fin base 63.3–72.9; anal-fin base 37.1‒46.5; pelvic-fin length 18.3‒39.3; caudalfin length 45.4‒67.4; body depth at anal-fin origin 19.5‒25.8; head length 19.3‒26.0; upper jaw length 9.9‒12.8; upper jaw depth 5.0‒6.4; orbit diameter 8.1‒11.9. As percentages of head length: upper jaw length 47.4‒53.4; orbit diameter 40.1‒49.8.

Comparisons. Three species have many of the diagonistic characters of Owstonia sibogae but differ (characters of O. sibogae in parentheses) as follows: Owstonia hastata has anal fin II, 14 (vs. II, 15–17), oblique body scale rows in mid-lateral series 38 (vs. 27–30) and more precaudal vertebrae and anal-fin pterygiophores anterior to 1st haemal spine 13 and 5 respectively (vs. 12 and 4); O. elongata has more dorsal-fin soft rays 24–26 (vs. 23, rarely 24), typically with anal-fin spine I, exceptionally II, see Table 4 (vs. II) and more precaudal vertebrae and anal-fin pterygiophores anterior to 1st haemal spine 16 and 8 respectively (vs. 12 and 4); O. contodon has more body scale rows in mid-lateral series ca. 48–53 (vs. 27–30) and premaxillary stripe extending entire length of premaxilla (vs. short stripe, extending only about 2/3 length of premaxilla). Four other species ( O. fallax , geminata , macrophthalma and whiteheadi ) agree with O. sibogae in having LL pattern type 1, dorsal-fin spines IV and spines on the lower limb of the preopercle but differ in having anal-fin spines I (vs. II). In addition, O. geminata has the inner membrane covering the posterior part of the dentary pale (vs. dark), and the other three species have more oblique body scale rows in mid-lateral series 39–54 (vs. 27–30).

Etymology. Named for the East Indies Siboga Expedition. The results of the "Siboga-Expeditie" (published in many parts from 1901 to 1986) were edited by Max Weber.

Distribution. ( Fig. 26 ) Vietnam, Philippines, and Indonesia where trawled in 183– 315 m.

Remarks. Weber's (1913) original description and drawing ( Fig. 74 ) of Sphenanthias sibogae were very inaccurate, especially in reporting 9 instead of 4 dorsal-fin spines and only a single cheek scale. Myers' (1939) comparison of Sphenanthias pectinifer and S. sibogae was not based on his personal examination of any types of Sphenanthias sibogae . While questioning the accuracy of Weber's description, he seems to have relied primarily on the total gill raker counts (38‒39) reported in Weber and de Beaufort (1931) for the holotype and three paratypes of S. sibogae , versus 45 for the holotype of S. pectinifer as justification for his new species. Total gill rakers counts ranged from 41–48 in 13 specimens of O. sibogae (see Table 7 ) we examined, suggesting that some of the very small gill rakers near the ends of the gill arch were not counted by Weber and de Beaufort. As indicated in the above synonymies, Endo et al. (2016) designated ZMA 112.568 as the lectotype of Sphenanthias sibogae .

Figures

FIGURE 8. Margins of preopercle lower limb (not drawn to scale), showing relative spine development in selected species of Owstonia: A, O. contodon, USNM 438013, 162 mm SL; B, O. elongata, USNM 432454, 110 mm SL; C, O. geminata, ASIZP 68128, 79 mm SL; D, O. maccullochi, holotype (right side reversed), AMS IA. 5815, 156 mm SL; E, O. maccullochi, NTM S. 11765 − 001, 146 mm SL; F, O. rhamma, holotype, MNHN 1995 – 0005, 102 mm SL; G, O. sarmiento, ANSP 165126, 82 mm SL; H., O. scottensis, CSIRO H. 7136 − 04, 103 mm SL; I, O. sibogae, ANSP 152035, 113 mm SL; J, O. taeniosoma, CAS 133928, 126 mm SL; K, O. tosaensis, ANSP 153169, 100 mm SL; L, O. weberi, ZMUC P. 531552, 127 mm SL.

FIGURE 12. Cheek scales on left side in selected species of Owstonia: A, O. ainonaka, AMS I. 33437, 213 mm SL; B, O. doryptera, USNM 93166, 65 mm SL; C, O. elongata, MNHN 2008 – 1350, 110 mm SL; D, O. grammodon, USNM 93167, 67 mm SL; E, O. kamoharai, NTM S. 12631 – 017, 206 mm SL; F, O. kamoharai, CSIRO H. 2099 – 007, 408 mm SL; G, O. maccullochi, AMS I. 25806 ‒ 012, 141 mm SL; H, O. raredonae, SAIAB 82406, 97.4 mm SL; I, O. sibogae, CAS 33843, 126 mm SL.

FIGURE 15. Premaxillary stripes in selected species of Owstonia: A, O. hastata, NTM S. 11779 – 002, 124 mm SL; B, O. nudibucca, ANSP 151993, 224 mm SL, Mentawai Islands; C, O. sibogae, CAS 32914, 96 mm SL, Philippines; D, O. ainonaka, AMS I. 33437 – 002, 213 mm SL. Photographs by Sandra J. Raredon.

FIGURE 26. Distributions of selected species of Owstonia based on specimens examined.

FIGURE 73. Owstonia sibogae, ANSP 152035, 156 mm SL, Indonesia, Sumbawa. Photograph by Sandra J. Raredon.

FIGURE 74. Owstonia sibogae, Indonesia, Timor Sea. After Weber, 1913, pl. 2, fig. 4.