Description:

Dorsal spines: 13; Dorsal rays: 12-14; Anal spines: 2; Anal rays: 11-13.
Full bodied, laterally compressed, ovate small fish. Large scales with darker edges. Operculum and preoperculum scaled. Opercles not serrated. 
Colour. Pale brown base colour, yellowish dorsally and paler ventrally. 7 broad dark bars on head and body. Small spot on upper pectoral fin base. First bar on top of head behind eye, last bar on the caudal peduncle. Dark edge to spinous dorsal fin. Pectoral fin with dark rays and hyaline membranes. Soft dorsal, anal and caudal fins grey. Caudal fin forked with rounded lobes. 
 

Maturity: Lm unknown. Range unknown. Max Length: 23 cm TL. 

Inhabits lagoon and outer reefs in shallow areas exposed to mild or moderate surge (depth 0-3m). Highly territorial. Feeds on benthic algae, invertebrates and zooplankton. Oviparous, distinct pairing during breeding. Eggs are demersal and adhere to the substrate. Males guard and aerate the eggs. 

This species is not protected or subject to fishery regulations. It is caught in the fish trap fishery, but is an uncommon component of the catch, possibly because fishers will often release it when caught. 

Abudefduf septemfasciatus is similar to A. sordidus, but the former lacks the black spot on top of caudal fin base. 

Bray, D.J. 2018.  Abudefduf septemfasciatus in Fishes of Australia, http://fishesofaustralia.net.au/home/species/307 (06/07/19).

Froese, R. & D. Pauly. Eds. 2019. FishBase. https://www.fishbase.se/summary/Abudefduf-septemfasciatus (06/07/19).

Jenkins, A. et al 2017. Abudefduf septemfasciatus. The IUCN Red List 2017: e.T188453A1877191. http://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T188453A1877191.en.  (06/07/19).