Acyrtus pauciradiatus

Common Name

Noronha Clingfish

Year Described

Sampaio, de Anchieta, Nunes & Mendes, 2004


Dorsal Fin: 7-8
Anal Fin: 6-8
Pectoral Fin: 20-22
Caudal Fin: 11-12 total

Head large and flattened with a laterally compressed posterior end. Eyes large and dorsally placed. Mouth terminal and small. Interorbital less than eye diameter. Snout short. Anterior nostril with cirri. Posterior nostril adjacent. Gill membranes connected but free from isthmus. Branchiostegal membrane not contiguous with operculum (with a deep pocket between them). Subopercular spine well developed with a strong ventral groove and a patch of modified tissue adjacent. Ventral sucking disk well developed. Disk U-shaped and covered in numerous papillae. There are ten rows of papillae across width of disc region A, ten rows across width of disc in region B, and four or five rows across width of disc in region C. Region C with two separated patches of papillae on the anterolateral margin. Dorsal and anal fins located far back on body and are across from each other. Caudal fin truncate. Fleshy pad on lower pectoral base absent.


Head reddish with dense small orange-red spots on body. Eye bright red with darker blotches, a thin red ring around pupil, and a dark red outer ring. Lower head and belly yellow. Body posterior to pectoral fin pale to whitish with five complete equally spaced bands. The bars are slightly displaced rearward below the lateral midline. The bands and pale interspaces have numerous red-orange spots that are similar to larger in size to the spots on head. Faint darker bands often cross head and run from eyes to side of head. Median fins pale with red-brown spots on finrays like the adjacent body. Dorsal fin with a blotch on the front contiguous with the body band below it. Paired fins clear.


A tiny species: largest to 16.3mm SL.


Coral reef areas rich in calcareous algae, sponges, and coral cover.


Known only from off Brazil: may be endemic to the Fernando de Noronha Archipelago.


Conway, K.W., Baldwin, C., & M.D. White. 2014. Cryptic diversity and venom glands in western Atlantic clingfishes of the genus Acyrtus (Teleostei: Gobiesocidae). PloS One, 9(5), e97664.

Sampaio, C.L., Nunes, J.D.A.C., & L.F. Mendes. 2004. Acyrtus pauciradiatus, a new species of clingfish (Teleostei: Gobiesocidae) from Fernando de Noronha Archipelago, Pernambuco state, Northeastern Brazil. Neotropical Ichthyology, 2, 206-208.

Other Notes

Can be easily distinguished from other Acyrtus by the relatively low finray counts, and by geographic range.