Roa semilunaris Matsunuma & Motomura, 2022
Half-moon barred butterflyfish
Roa semilunaris
photo by National Museum of Nature and Science, Japan

Family:  Chaetodontidae (Butterflyfishes)
Max. size:  11.03 cm SL (male/unsexed)
Environment:  reef-associated; marine; depth range 102 - 123 m
Distribution:  Western Indian Ocean: Mascarene Ridge.
Diagnosis:  Dorsal spines (total): 11-12; Dorsal soft rays (total): 20-21; Anal spines: 3-3; Anal soft rays: 16-17; Vertebrae: 24-24. This species is distinguished from its congeners by the following set of characters: pored lateral-line scales 37-41; black blotch present on each membrane associated with first and second dorsal-fin spines; upper jaw is covered with scales; pelvic-fin spine and distal portion of 1st soft ray are whitish, while remaining portions of fin dusky to black; second black body band crossing pectoral-fin base, and is interrupted by many pale narrow lines; ocellated blotch on the dorsal-fin soft-rayed portion semicircular or oval, with long axis/short axis ratio 1.6-2.0 (Ref. 126057).
Biology: 
IUCN Red List Status: Not Evaluated (N.E.) Ref. (130435)
Threat to humans:  harmless


Source and more info: www.fishbase.org. For personal, classroom, and other internal use only. Not for publication.