222 
THE CORAL TRIANGLE: HEARST BIODIVERSITY EXPEDITION 
detritivore and adventitious carnivore, Eucidaris metularia). Micropyga is characterized not only 
by peculiar, hoof-shaped oral spine tips (Figs. 5B, C), but by the strangest tube feet known in any 
echinoid (Fig. 5D). The aboral tube feet of Micropya are extremely long, and tipped with very 
sticky, umbrella-like expansions (Mortensen 1940a). The stickiness of the tips results in their 
wholesale removal from specimens during trawling operations, as illustrated by Burch (2001: Fig. 
1) — although she mistakenly attributed the tube feet to a spatangoid, not a micropygid. The func¬ 
tions of these peculiar tube feet are unknown, but one hypothesis advanced during observations of 
the living, relatively undamaged animals from the fish traps was that the tube feet were extended 
upwards into the water column as “fishing lines” capable of capturing living prey such as small 
cmstaceans. This would agree well with the apparent attraction oiMicropyga to the protein bait of 
the traps. However, work by Mortensen (1940a), and subsequent dissection of specimens on board 
the M/V “DA-BFAR” revealed only fragments of plant material and spicules of sponges — a diet 
typical of many deep-sea echinoids lacking any specialized tube feet. Therefore, the function of the 
bizarre tube feet remains obscure, although it cannot yet be mled out that they are used in food 
gathering. 
Work on Philippine echinoids continues at the Academy, and findings of the Expedition have 
Figure 5. Micropyga violacea. A. Aboral view of live speeimen on board the M/V “DA-BFAR”. B. Oral view of same 
speeimen. C. Hoof-like tips of oral loeomotory spines (arrow). D. Slightly magnified view of speeimen in A showing long, 
string-like, white shafts of aboral tube feet terminating in stieky, umbrella-like tips (arrow). Seale bar 10 mm long. 
