Nudiantennarius subteres

Lore & Background

Nudiantennarius subteres was first formally described in 1912 by Hugh McCormick Smith and Lewis Radcliffe, with its type locality given as Lingayen Gulf in western Luzon, Philippines. The genus Nudiantennarius was proposed in 1957 by American ichthyologist Leonard Peter Schultz, who designated Antennarius subteres as the type and only species. An unidentified frogfish from Lembeh was identified as this species in 2017. Within the family Antennariidae, this taxon has been found to be most closely related to the sargassum fish (Histrio histrio). Some authorities classify it in the subfamily Antennariinae, though the 5th edition of Fishes of the World does not recognize subfamilies within Antennariidae.

The species is distinguished by its reduced number of bifurcate dermal spinules, so few that the body appears naked. The illicium (first dorsal spine) is naked without spinules and about half the length of the unusually long second dorsal spine, which is slender and not connected to the head skin by a posterior membrane. The pectoral fin lobe is thin and somewhat separated from the sides. The esca (lure) is small, round, with short filaments, and fits into a thin groove beside the second dorsal spine. There is typically at least one large ocellus on the base of the dorsal fin.

Nudiantennarius subteres is found in the Western Pacific Ocean in the Philippines, Indonesia, and off Japan, inhabiting depths between 3 and 128 m. It is usually encountered on substrates of brown or black sand, silt, or mud, sometimes with soft coral, gorgonians, or sponges, but very few hard corals. It has also been found on pier pilings, among seaweed, and in areas with leaf litter and refuse near human habitation. Dark-colored individuals are most numerous on coarse sand or gravel with green algae at depths of 4 to 20 m, while lighter, more colorful individuals are typically found with small sponges at depths of 12 to 30 m. This is an oviparous species.

Reader's Guide

The deepwater frogfish, Nudiantennarius subteres, holds significance as the sole member of its genus, Nudiantennarius, which was erected in 1957 by Leonard Peter Schultz. Its most notable characteristic—the reduced spinulation that gives it a naked appearance—sets it apart from other frogfishes and is reflected in its genus name, derived from Latin nudus meaning 'nude' or 'naked.' The species' unusually long second dorsal spine and the presence of a caudal peduncle further distinguish it within the family Antennariidae. Its close phylogenetic relationship to the sargassum fish (Histrio histrio) provides insight into the evolutionary history of frogfishes. The species was originally described in 1912 from the Philippines, and a 2017 identification of an unidentified frogfish from Lembeh expanded its known range. Its habitat preferences—ranging from sandy and muddy substrates to pier pilings and areas near human habitation—demonstrate its adaptability. The species is most commonly observed on night dives off Bali, and its color variation with depth suggests behavioral or ecological adaptations. As an oviparous fish, its reproductive biology aligns with other frogfishes, though specific details of its spawning behavior remain undocumented in the source article.

Did You Know?

• The genus name Nudiantennarius combines Latin nudus ('naked') with Antennarius, referring to the species' nearly naked skin due to reduced spinules.
• The specific name subteres means 'less than cylindrical,' thought to allude to the body shape.
• This species has a maximum published standard length of only 7.5 cm (3.0 in).
• It is most closely related to the sargassum fish (Histrio histrio) within the family Antennariidae.