trio, in situ
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 and may be feeding on the translucent brown sponge in the "in situ" photo. 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, French Frigate Shoals and Kure: widely
distributed in the western and central Pacific.
This species is listed as Chromodoris decora 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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