Cirrate octopods, cephalopods
known as the dumbo octopuses
are among the largest invertebrates of the deep sea. These organisms have long been known to lay single, large egg capsules on hard substrates on the ocean bottom, including cold-water octocorals. Although
juveniles have previously been collected
in the midwater, cirrate hatchlings
have so far never been observed. However, researchers has been able to locate a dumbo octopus eggs in a submarine mountain at 1,900 m, and have discovered that they look and act like adults from the moment they hatch.
The egg capsule is comprised of an
external egg case as well as the chorion
and developing embryo. Development
in cirrates proceeds for an extended
time without parental care
-
Dumbo octopus hatchling, with opened egg case attached to octocoral Chrysogorgia artospira collected at 1,965 m depth on Kelvin Seamount, Atlantic Ocean.
The baby dumbo octopus behavior shows that cirrate hatchlings possess all morphological features required for movement via fin-swimming, for visually and chemically sensing their environment, and for prey capture. The presence of a large internal yolk sac reduces the risk of failure at first feeding. This is enough evidence that dumbo octopods hatch as competent juveniles.
Cold-water octocorals appear to be critical in cirrate life cycle, and their destruction by bottom trawling or mining will impact populations of mobile animals like the charismatic dumbo octopods
Anthias (subfamily Anthiinae of the Serranidae family) are perhaps the most consistently colourful and attractive of all reef inhabitants. Almost all species exhibit stunningly bright and patterned forms, some of which are amongst the most iconic and ubiquitous amongst reef imagery (for example, the Lyretail Anthias, Pseudanthias squamipinnis, which can be regularly seen in reef photography). Amongst these, the most easily recognisable are the members of the genus Pseudanthias - the imposter Anthias.
Almost all members of the genus exhibit strong sexual dichromatism, or in plain English, a marked visual difference between the adult genders. All are sequential protogynous hermaphrodites, meaning they commence life as sexually immature females, but given appropriate social cues, can transition to various states of the male gender. There is four typical states in the life history of any member of the genus: initial/submissive female, dominant female, subdominant/initial male, and “supermale” or terminal male. Also, many species exhibit strong sexual physiological differences; many of the dominant males will exhibit an enlarged dorsal filament (usually from the second or third dorsal spine) for example.
These fish are common in the aquarium trade, however many species are considered to be too difficult for captive life due to several factors. Many of the species are deepwater pelagic swimmers in nature meaning they come from open water at significant depths - in excess of 200m in some species - and so seldom adapt to the conditions of the typical aquarium. Part of the problem also comes from their diet being strictly pelagic zooplankton - tiny marine crustaceans that swim freely in the water. Their metabolism is necessarily fast and so they spend much of their time actively feeding from the water column.
On display here are some of the more seldom seen of the genus. This is usually because of their remoteness of range and depth. Some of them are only ever seen by closed-circuit divers in the right place at the right time, hence the fairly recent discovery of several of the above. To my mind, they’re also some of the most gorgeous of the genus - one of the most beautiful groupings in the sea.
Most of these exhibited are of the terminal male phase, which is almost ubiquitously to the genus the most colourful and extravagant of the colour forms. Males are the masters of harems - sometimes numbering into the many hundreds - and have an incredibly involved social structure under their watch. This can often lead to violent disagreements, providing a pathway for succession by subdominant specimens when a dominant is injured or killed.
Anthias. Some would say that a reef just cannot be as exciting or vibrant without their stunning and intense presence.
Prickly dogfish (Oxynotus bruniensis). Look at this idiot.
Prickly dogfish are actually sharks, and we actually know very little about this species. Like, for instance, why their skin is so rough as to look furry. We do know these guys are one of the few sharks that give live birth! They’ve been found gestating up to seven pups at a time.
They live, somewhat appropriately, in the “Twilight Zone” (Mesopelagic Zone, 200-1000 meters below the surface) off the shores of Australia and New Zealand.
My hottest take is that every single Pole is a goth fuck with no style, also anyone who lays plastic flowers on my grave in the future is going to get their ass kicked by my vengeful ghost so don’t even try it
Plastic znicze are acceptable but you’re on thin fucking ice
actually hold on, retracting the glittery spruce znicz question
although I absolutely hate the kitschy plastic things, this death aesthetic™ is somewhat pleasing
