Sphagemacrurus Fowler, 1925

Nakayama, Naohide, 2020, Grenadiers (Teleostei: Gadiformes: Macrouridae) of Japan and adjacent waters, a taxonomic monograph, Megataxa 3 (1), pp. 1-383 : 276-277

Genus Sphagemacrurus Fowler, 1925

[No Japanese name]

Sphagemacrurus Fowler, 1925:3 (as subgenus of Macruroplus ; type species: Macrurus hirundo Collett, 1986 , by original designation).

Grenurus Parr, 1946:46 (type species: Grenurus grenadae Parr, 1946 , by original designation).

Diagnosis. Anus closer to anal-fin origin than to pelvic-fin bases. Periproct broadly developed, extending about 2/3 of distance between anal-fin origin and pelvic-fin base. Small dermal window of light organ immediately anterior to anus, its anterior margin well posterior to pelvic-fin bases. Infraorbital ridge not connected with preopercular ridge, separated by distinct gap. Second spinous ray of first dorsal fin serrated along its leading edge. Ventral aspects of body positioned forward so that anal-fin origin distinctly anterior to hind margin of first dorsal-fin base. Snout scarcely protruding beyond upper jaw, its ventral profile almost vertical. Chin barbel present. Teeth in bands in both jaws; premaxillary band ending anterior to posterior edge of maxillary process. Tip and lateral angles of snout tipped with prominent scutes; suborbital shelf formed of stout, coarsely modified scales. Body scales covered with needle-like spinules in parallel to slightly divergent rows; buttresses of spinules rudimentary; reticulate structure broadly developed. Underside of snout variously naked. Grooved lateral line present. Pyloric caeca usually less than 30. Branchiostegal rays 7. Body generally dark, lacking silvery reflection when fresh. [Modified from Iwamoto & Merrett (1997) and Iwamoto & Graham (2001).]

Remarks. Sphagemacrurus includes six nominal species, all of which are currently treated as valid ( Iwamoto 1990), viz., S. decimalis ( Gilbert & Hubbs, 1920) , S. gibber ( Gilbert & Cramer, 1897) , S. grenadae ( Parr, 1946) , S. hirundo ( Collett, 1896) , S. pumiliceps ( Alcock, 1894) , and S. richardi ( Weber, 1913) .Citing a personal communication from Yuri Y. Sazonov (ZMMGU), Iwamoto & Merrett (1997:548–549) suggested that half of these species are of dubious validity. They also implied that the S. pumiliceps specimens they reported from the New Caledonian region may represent another species or include two different taxa. This elusive genus needs a through revision ( Iwamoto & Merrett 1997; Iwamoto et al. 2015).