Owstonia similis

description

Description. A species of Owstonia with LL pattern type 1, consisting of 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 ray 16. Dorsal fin III, 21; anal fin I, 14; pectoral fin 22 / 21; gill rakers 10 + 22 / 23. Vertebrae: precaudal 11, caudal 17, total 28; anal-fin pterygiophores anterior to 1 st haemal spine 2. Oblique body scale rows in mid-lateral series 52 – 56; nape scaly and cheek scale rows 6. Lower limb margin of preopercle without spines. Papillae in slight depression behind tip of premaxillary ascending processes difficult to discern with absolute certainty, but they appear to be in two closely spaced rows with 3 large, almosttouching papillae in anterior row and 2 smaller papillae on opposite ends of the posterior row. Teeth in outer row of each premaxilla 10 / 13; no inner teeth anteriorly. Teeth in lateral row of each dentary 10 / 8; symphyseal teeth 3, spike-like, and with 1 smaller inner tooth anteriorly. Pelvic fin short, depressed fin extending only to anus. Caudal fin lanceolate. Caudal fin 2.5 times in SL; head

Hidden diversity in deep-water bandfishes: review of Owstonia with descriptions of twenty-one new species (Teleostei: Cepolidae: Owstoniinae)

diagnosis

Diagnosis. A species of Owstonia with LL pattern type 1; dorsal fin III, 21; anal fin I, 14; oblique body scale rows in mid-lateral series 52 ‒ 56; lower limb margin of preopercle without spines; dorsal fin anteriorly with several of the interradial membranes mostly black.

Hidden diversity in deep-water bandfishes: review of Owstonia with descriptions of twenty-one new species (Teleostei: Cepolidae: Owstoniinae)

discussion

Remarks. We cannot entirely eliminate the possibility that the total number of gill rakers (32 – 33) in the 88.6 SL holotype of O. similis compared to those (37 – 38) in the much larger, 116.2 SL, holotype of O. melanoptera is correlated with body size. However, in Owstonia species with relatively low numbers of total gill rakers, gill rakers usually increase only slightly by the time specimens have obtained a size of about 80 mm SL.

Hidden diversity in deep-water bandfishes: review of Owstonia with descriptions of twenty-one new species (Teleostei: Cepolidae: Owstoniinae)

distribution

Distribution. (Fig. 27) Known only from the Madagascar type locality, where trawled in 347 – 448 m.

Hidden diversity in deep-water bandfishes: review of Owstonia with descriptions of twenty-one new species (Teleostei: Cepolidae: Owstoniinae)