Janolidae

Janolidae is a family of marine flatworms in the order Polycladida. They are commonly known as “janolinids” or “janolans”. Janolidae are known for their colorful and often intricate body patterns, ranging from bright yellow and orange to vibrant blues and greens. These flatworms can be found in a variety of marine habitats, including rocky shores, coral reefs, and seagrass beds.

Toyama Nudibranch – Janolus toyamensis

Nudibranch – Janolus mirabilis

Crested Aeolis, Electric Blue Nudibranch – Antiopella cristata

Cockscomb Nudibranch, Santa Barbara Nudibranch – Antiopella barbarensis

Nudibranch – Antiopella novozealandica

Cape Silvertip Nudibranch – Antiopella capensis

White And Orange Tipped Nudibranch – Antiopella fusca

Characteristics

Members of Janolidae are characterized by their flattened, elongated bodies, which can be up to several centimeters in length. They typically have a single opening that serves as both a mouth and anus. Like other polyclads, they possess a complex digestive system with numerous branching diverticula, allowing them to efficiently process food. Unlike other Polycladida, Janolidae are usually characterized by a small number of eyes.

Environments

Janolidae are found in a wide range of marine environments, including:

  • Rocky shores
  • Coral reefs
  • Seagrass beds
  • Intertidal zones
  • Subtidal zones

Feeding Habits

Janolids are carnivorous and feed on a variety of smaller marine invertebrates, including:

  • Bryozoans
  • Hydroids
  • Other flatworms
  • Small crustaceans

Reproduction

Janolids are hermaphroditic, meaning they possess both male and female reproductive organs. They reproduce sexually, with internal fertilization and external development of embryos.

References