Dendronotidae Family of Nudibranchs

One Nudibranch of the Dendronotidae Family can be found in this website:

Giant Nudibranch, Dendronotus iris. A representative of the Dendronotidae Family of Nudibranchs.

Phylogeny: Nudibranchs of the Dendronotidae Family are sea slugs in the phylum Mollusca and the order Nudibranchia. They are soft-bodied gastropods that lose their shells during their larval phase. Nudibranchs have “naked gills” exposed on their backs that are utilized to separate nudibranchs into two main classifications, the aeolids and the dorids. The Aeolids have a mantle that forms a series of finger-like projections (cerrata) along the entire back of the animal. The Dorids have a thick mantle on their back (dorsal surface) that extends over the foot. Their gills consist of feathery plumes that encircle the anus. The order Nudibranchia is comprised of six suborders and thirteen superfamilies. The Dendronotidae Family is in the suborder Dendronotina and the superfamily Dendronotoidea. Dendronotidae is one of eight families within this superfamily. The Dendronotidae Family is moderately large, with three genera and around forty-one species. The name Dendronotidae comes from the Greek words meaning “tree” and “back”. This refers to the branching processes on the dorsal surface. Nudibranchs in the Dendronotidae Family are also known as Dendronotids.

Morphology: Dendronotids are aeolids with elongated bodies and with numerous branching cerata on the lateral edges of the dorsum. The cerata act as secondary gills and also contain extensions from the digestive gland which vary in extent between species. These cerata generally get smaller toward the posterior of the animal.  The head has an oral veil having up to 5 pairs of velar processes. Like all nudibranchs, Dendronotids have rhinophores (horn-like projections) on their heads that are chemosensory organs that help them to locate food and potential mates. Their lamellate rhinophores are retractable and are surrounded by a sheath and branched papillae.  Dendronotids lack complex eyes, but have photo-receptors that sense light and dark. Despite their inability to see color, nudibranchs are some of the most brightly colored of all animals. They derive the pigments for their color from the food they eat. Dendronotids reach a maximum of 30 cm (12 inches) in length.

Habitat and Distribution: Dendronotids are found on hard surfaces and soft substrates. They are found intertidally and to depths up to 3,000 m (9,840 feet). Dendronotids are found worldwide, in tropical to polar seas. Two species in the Dendronotidae Family are found in Mexican waters.

Reproduction: Dendronotid Nudibranchs are simultaneous hermaphrodites (having both male and female reproductive organs). They reproduce sexually. Copulation requires two individuals to face opposite directions, with their right sides touching. They pass sperm packets through a tube called the copulatory apparatus. After being fertilized internally, the eggs are laid in coiled, gelatinous, strings, attached to the substrate or on the tubes of their prey.

Ecosystem Interactions: Dendronotids feed primarily on hydroids, but also prey on tube-dwelling anemones, polyp-stage jellyfish and polychaete worms. In turn they are preyed upon by sea stars and other nudibranchs.