More than 2200 species of the wild flora and fauna photographed in Zihuatanejo, Guerrero, Mexico and the surrounding area.
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Molluscs of Zihuatanejo
PHYLUM MOLLUSCA
Doriopsilla janaina
-Gastropods (Class Gastropoda)
-Heterobranchs (Subclass Heterobranchia)
-Infraclass Euthyneura
-Subterclass Ringipleura
-Superorder Nudipleura
-Nudibranchs (Order Nudibranchia)
-Suborder Doridina
-Infraorder Doridoidei
-Superfamily Phyllidioidea
-Family Dendrodorididae
-Genus Doriopsilla
-Doriopsilla janaina
The Doriopsilla janaina is a small, brightly colored dorid nudibranch found in the tropical eastern Pacific, including coastal Mexico and Central America. Like other members of the genus Doriopsilla, it has a smooth, oval body with a soft, slightly flattened profile and a broad mantle that overhangs the foot. Its coloration is typically vivid yellow to orange, The rhinophores—paired sensory structures on the head—are club-shaped and often slightly darker or more opaque than the surrounding body, while the gill plume forms a delicate cluster toward the rear of the mantle. This species inhabits shallow rocky reefs and coral communities, usually on or near sponges, which form the primary component of its diet. Like many dorid nudibranchs, it likely sequesters chemical defenses from the sponges it consumes, making it distasteful to predators.
Description
The knobby sea slug (Doriopsilla janaina) is a small marine nudibranch in the family Dendrodorididae. Its oval, flattened body has a soft, shell-less mantle covered with rounded tubercles of varying sizes. Colour ranges from translucent pale orange to deep reddish-orange, often with white patches, small dark spots, and larger tubercles tipped with orange or white. The rhinophores on its head and the cluster of feathery gills on its back are often similarly coloured. Adults reach approximately 3 cm in length.
Range
This species occurs in the tropical eastern Pacific. Its known distribution includes the Pacific coast of Panama and the Gulf of California in Mexico, extending along Mexico's Pacific coast, including Zihuatanejo, Guerrero.
Habitat
Doriopsilla janaina inhabits rocky intertidal shores and shallow subtidal environments, from tide pools to depths of approximately 20 m. It shelters beneath rocks and among rocky reef surfaces, where its mottled colour and textured mantle help it blend into its surroundings.
Diet
The knobby sea slug feeds on marine sponges. Like other members of its family, it lacks a radula and instead uses digestive enzymes to break down sponge tissue externally before absorbing the resulting material.