Goniobranchus cavae (Eliot, 1904) species complex

(Figures 6 B–G)

Material examined. Eleven specimens. MB28-004546, ZRP, 20 May 2012, 2m, 26mm; MB28-004562, ZRP, 0 4 Jun. 2012; MB28-004946, ZJS, 13 Dec. 2014, 14m, 32mm; MB28-0 0 4869, VAL, 23 May 2014, 3m, 78mm; MB28-004871, VAL, 24 May 2014, 3m, 72mm; MHN-YT1266, VAL, 23 May 2014, 3m, 81mm; MB28-004873, VAL, 23 May 2014, 3m, 82mm; MB28-004924, ZRP, 19 Aug. 2014, 0.5m, 28mm. MB28-004612, ZWH, 22 Aug. 2012, 18m, 32mm; ZMBN117046, ZGWS, 13 Sep. 2013, 21m, 47mm; MB28-00 4969, ZY, 27 Feb. 2015 60m, 60mm.

Habitats. Subtropical tidal reefs, rocky reefs, seagrass and artificial reefs.

Occurrences. Zavora and Vilanculos.

Geographic distribution. Indian Ocean. Gulf of Oman (Fatemi & Attaran-Fariman 2015), Tanzania (Eliot 1904c), South Africa (Gosliner 1987; Coleman 2008), Réunion (Yonow 2012) and Mozambique (King & Fraser 2014).

Remarks. Goniobranchus cavae is highly variable in colour and at least three species have similar colour pattern: G. tennentanus, G. cavae and G. leopardus . Yonow (2012) provides morphological differences between them and gives details on G. cavae colour variations. Both morphotypes illustrated by Yonow (2012; pg. 105, plate 37 and pg.106, plate 38) were found in Mozambique. Gosliner et al. (2015) show a third morphotype of G. cavae (pag. 228, bottom right), which is also similar to one of the specimens collected by us (Fig. 6 D). Contradictorily, Gosliner et al. (2015) consider one of the morphotypes illustrated in Yonow under the name G. cavae (2012, pg. 105, plate 37) as an undescribed species ( Goniobranchus sp. 19, pg. 220, bottom left). This last morphotype differs from others by the orange background instead of orange spots and is potentially a different species.