But the specific designs and colors are sufficiently different from the familiar black saddled toby (Canthigaster valentini) to suggest they’re not described in any of the references I have access to.
But there are a lot of fishes in the sea, so to speak, and many of them haven’t actually found their places in the books. So for the purposes of this blog I’ll just call them Canthigaster neptuneswebus. (Yeah, actually naming things is much harder than that).
BRITTLESTARS ON DUTY
The point of this shot is that they were photographed sleeping on a sponge during a night dive in the Philippines — a time when the brittlestar in between them, apparently an Ophiothrix purpurea, is most likely to be found fully exposed (“apparently” because my sources on this animal don’t place this particular species in the Philippines either).
Although I haven’t seen a rule about it, during the daytime one tends to see only parts of brittlestars — legs dangling from the crevices or vase sponges where they are mostly hiding. They’re most likely to be seen in full frontal star-ness at night.
Brittlestars, found in both the Indo-Pacific and the tropical Atlantic/Caribbean, are closely related to more familiar seastars, with the principal difference that the tube feet on brittlestar arms lack suckers and are used for feeding. Their arms are used to filter plankton from the current and their tube feet produce a mucus that collects microorganisms and detritus from the surfaces on which they settle.
In fact, when one sees a hidden brittlestar’s arm extended from a hiding place, there’s a good chance that arm is at work, trolling for food. If touched by a predator, brittlestars can shed parts or all of their arms and regenerate. They can move relatively rapidly by vigorous rowing movements with their arms.
Principal Sources (or not): Indo-Pacific Coral Reef Field Guide, Gerald Allen, Roger Steene; Coral Reef Animals of the Indo-Pacific, Terrence Gosliner, David Behrens, Gary Williams; Reef Fish Identification — Tropical Pacific, Gerald Allen, Roger Steene, Paul Humann, Ned DeLoach