January-April, 2013 
SCAMIT Newsletter 
Vol. 31 Nos. 5-6 
Caudina arenicola is a sand encrusted, plump species that is “peanut-worm” shaped with a small 
tail. The species has very delicate ossicles and tables that almost appear to be “disintegrating” 
according to notes from several small (1 cm or so) specimens. The tables have large holes in the 
plate portion of the ossicle. Don Cadien mentioned that specimens from LACSD are typically 
larger and not covered by fine sand. Since CSD only sees small, juvenile specimens (usually 1 cm 
or less) the identification of CSD specimens is tentative. 
Phyllophoridae sp A Lilly. See the SCAMIT voucher sheet in the Tools section of the SCAMIT 
website. The apparently undescribed species has a complete lack of ossicles in the tube feet, 
and delicate tables in the body wall. The body is white with widely distributed delicate tube feet 
that show no distinctive pattern. It is found in 30^5m depth among relict red sands and coarse 
sediments. 
Megan then moved on to discuss members of Parastichopus (Stichopodidae). Based on Bight’08 
results there seems to be wide-ranging variability in both P. californicus and P. sp A. Megan 
showed a series of field photos from Bight’08 that showed a range of morphologies for both 
species. She worries there might be undescribed species of Parastichopus in the So Cal Bight. 
As a result, Megan proposed putting together a set of photos of “acceptable” P. californicus and 
“acceptable” Psp A, which people can take in to the field for the upcoming Bight’ 13 project. 
Specimens that do not fit within these pre-ordained ranges of variability should be recorded as 
''Parastichopus sp.” These specimens should be photographed live (including size scale within 
photo) and clipped for body and tube feet tissue. 
The problem with ossicle mounts of Parastichopus specimens is that they rely on micro¬ 
measurements of ossicles to determine species identifications. See Lambert (1986) which 
describes one new species of Parastichopus and includes a review of common taxa. Lambert uses 
ossicle sizes to distinguish taxa. This genus would be a good candidate for DNA work. 
For Bight’ 13, Megan volunteered to create one field sheet per agency prior to the July trawl 
surveys. 
We then moved on to ophiuroids and their associated SCB taxa. Megan strongly urged everyone 
to dry specimens of Amphiodia urtica, A. digitata, A. psara, and Amphiodia sp A and use side¬ 
lighting (to create contrast/depth of field) to view the scale patterns and hyaline forks of the disc, 
oral papillae, dorsal arm plates, etc. 
Amphiodia psara is pigmented on both the disc and the arm plates, which can be helpful but 
not relied upon since other taxa are also pigmented. A. psara has blunt, round-tipped arm spines 
vs. the tapered, sharp-tipped arm spines of^. urtica and A. digitata. The dorsal arm plates are 
rectangular with comers touching. The primary plates are evident as a rosette. 
Amphiodia digitata has large scales on the dorsal disc cap, and there is a single row of hyaline 
forks that mns along the dorso-lateral edge of the cap. Ophiuroid specimens with multiple, 
crowded rows of hyaline “spines” can occur but they should not be called A. digitata. Each 
hyaline “fork” can have two or more spires. The dorsal arm plates are rectangular and adjacent 
plates touch along their front-to-rear edges. You need all three characters present (large dorsal 
disc cap scales, single row of hyaline forks, and rectangular dorsal arm plates) to call a specimen 
A. digitata', if you don’t have all three characters, an ID of Amphiodia sp is suggested. A. digitata 
is typically found in coarse sediments. 
10 
Publication Date: 28 July 2016 
