trio, in field
Goniobranchus decorus (Pease, 1860)
|Maximum size: 20 mm.
species can vary in pattern but can usually be
identified by its translucent body with a
white median line that bifurcates midway along the notum to form a "Y"
that circles around the gills. Another white line forms a loop around
the median line. There is a marginal orange band and the notum is
decorusted with large purple
spots. Mantle glands can often be seen
around the margin beneath the orange border. The rhinophores and gills
is a common species although it is seldom seen due to its small size
and nocturnal habits. It may be found in tide pools and from the low
intertidal to 10 m (32 ft) on protected to exposed rocky
bottoms. Scott Johnson reports it feeding on a jet black sponge in
Hawaii (pers. com.).
However, it's also been reported feeding on several other species. Its
egg mass is pale orange and each egg is associated with a small cap of
dark orange extra-capsular yolk.
Big Island, Maui, Oahu, Kauai, Niihau, French Frigate Shoals, Midway and Kure (also Johnston Atoll): widely
distributed in the western and central Pacific.
This species is listed as Chromodoris decora (corrected in 2019 printing) and referred to as
the "decorated nudibranch" in Hoover, 1998 & 2006. It's also listed as C. decora in Bertsch & Johnson, 1981, Kay, 1979 and Kay & Young, 1969. It was first
reported from Hawaii in Pease, 1860 (as Doris decora). The name means "pleasing."
Photo: PF: 11
mm: found by CP; Napili Bay, Maui; May 6, 1993.
Observations and comments:
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