Boloceroides daphneae Daly, 2006
Base and column: The column is smooth, stout, of ca. equal diameter throughout in preserved specimens, slightly flaring proximally. Live specimens are pale pink to purplish-red in colour. Preserved specimens are paler, beige to maroon in colour. In preserved specimens, the proximal edge of the column is slightly darker and crenulated where it meets the base. The edge of the column may extend slightly beyond the pedal disc. The pedal disc is adherent, and is the same colour as the column, ca. equal in diameter to oral disc in both preserved and live specimens. In preserved specimens there are concentric rings of contracted muscle surrounding a small central depression. Basilar muscles are absent. The mesenteries may be visible through the column wall at the junction with the base, giving the proximal column a lightly striped appearance. The column has strong ectodermal longitudinal muscles and numerous spirocysts. The mesoglea is homogenous, hyaline, and has few lacunae or cells. There is no marginal sphincter muscle.
Oral disc and tentacles: The oral disc of living anemones is obscured by a dense crown of extremely long tentacles. The tentacles are slightly domed to flat, and creamy pink to pale purple in colour in preserved specimens. The mouth is central, with prominent, deep purple to maroon lips. The actinopharynx is the same colour as the oral disc, and is strongly ribbed, and may protrude through the mouth in preserved specimens. There are two weak, diametrically opposed siphonoglyphs, slightly lighter in colour than the actinopharynx and lips. A broad, flat, tentacle-free zone surrounds mouth The tentacles are crowded, densely covering the peripheral third of oral disc. The tentacles are slightly paler than or same colour as the oral disc, and numerous (>100). They are circular at the base and extremely long and tapering in live specimens. They are shorter, darker, and blunt-tipped in preserved specimens. The inner tentacles are significantly longer than the outer tentacles, and three to four times longer than column in life. They are typically held erect, but with tips that sometimes trail in living anemones. The distal tips of all tentacles are lighter and thread-like, and are often curled. The tentacles of preserved specimens are bluntly pointed, lighter distally, and are typically 80–120 mm long with maximum width of 10–15 mm. The tentacle sphincter is visible as a thickened ring on the oral disc base. The autotomized tentacle retains turgor, and is shaped like an elongate teardrop with a rounded base and a strongly pointed tip.
Mesenteries and internal anatomy: The mesenteries are arranged hexamerously in four cycles. The mesenteries of the first three cycles are perfect. There are two pairs of directives, each attached to a weak siphonoglyph. The mesenteries of higher cycles bear filaments and gonads distally, and taper to a thin, muscle- and filament-free sheet proximally. The mesenterial filaments of the stronger mesenteries are prominent, and are the same purple to maroon colour as the actinopharynx. The longitudinal muscles of the mesenteries are very weak, even in highly contracted preserved specimens. The mesoglea of the mesenterial lamellae is drawn into short processes on both surfaces near the junction with the body wall. No mesenteries have a concentrated parietal or parietobasilar muscle. The retractor muscle is extremely diffuse, and extends from the body wall to the reproductive region of the larger mesenteries as small, largely unramified processes on one surface of the mesentery.
Cnidom: Spirocysts, basitrichs, microbasic p-mastigophores are all present.
Ecology and Distribution
East Pacific Rise (8°36.687′N - 12°48.719′N and 103°56.467′W - 104°12.531′W) and depth of 2,400-2,650 m (Daly, 2006).
All the specimens collected in November 2003 were sexually mature and gonochoric, with large and conspicuous gametogenic tissue. Mature eggs were ovoid, and measured 3 mm long x 1.5 mm wide x 1 mm deep (Daly, 2006).