Scientific Name: Hexabranchus lacer (juvenile)

Adult Size: up to 400 mm (juveniles observed around 10 – 30 mm)
Depth Range: 1 – 30 m; commonly found on shallow reef slopes, lagoons, and outer reef environments

Biotope / Habitat:
Usually associated with coral reefs where sponge growth is abundant. Juveniles are often cryptic and can be found on rubble, reef walls, or among sponge-covered substrates where they blend in before adopting the more conspicuous adult lifestyle
Diet: Spongivore dorid nudibranch feeding on a variety of marine sponges. As it grows, it specializes further on sponge prey, from which it may also derive chemical defenses.
Reproduction: Simultaneous hermaphrodite; adults mate by aligning side by side and exchange sperm. They lay large, distinctive, ribbon-like or spiral egg masses often attached to reef structures. Larvae hatch as planktonic veligers before settling onto suitable sponge-rich habitats

Fun Fact: Juvenile Hexabranchus lacer looks completely different from the famous “Spanish dancer” adult. Instead of a large, flowing body with dramatic swimming behavior, juveniles are small, often patterned, and surprisingly discreet—making them a rare and exciting find for macro photographers who usually expect this species only in its iconic adult form!