Mourgona sp. #4
|Maximum size: about 25 mm.
Like Mourgona sp. #1, mature
animals of this species have flattened, leaf-like cerata covered
with small tubercles. The body is translucent cream liberally flecked
with white, orange and dark purple. Unlike that species, there is a
diffuse patch of violet pigment in the tip of each ceras and no cluster of purple
spots on top of the head. The greenish-brown
branches of the digestive gland in the cerata have noticeably sparser
side branches than in Mourgona sp. #1.
Mourgona sp. #4 is
known from several animals found at a moderately protected to moderately exposed sites at a depth
of 1-4 m (3-15 ft).
Unlike in M. sp, #1, the mature animals were found in the open during the day
and one became quiescent in a dish at night suggesting diurnal behavior.
Like M. sp. #1, it may contract its
cerata rhythmically while crawling.
Maui and Kauai. Widely distributed in the Pacific.
It was first
recorded in Hawaii from Hekili Point, Maui by CP on April 22, 2018. It appears identical to "Mourgona sp. 2" in Gosliner, et. al, (2018). (Note 1)
Photo: CP: 15 mm: Hekili Point,
Maui; April 18, 2019.
Observations and comments:
1: Two major color differences in the mature animals combined with the
difference in side branches of the digestive gland suggest that Mourgona sp. #1 and Mourgona sp. #4 are distinct and sympatric in Hawaii. The mature Mourgona sp. #4 also had fewer
black spots on the mid-line of the notum and few or no white/orange
spots on the foot. However, those differences might be due to
individual variation. The other differences seem consistent with photos from elsewhere in the Indo-Pacific.