Amphianthus lacteus (McMurrich, 1893)

Gusmão, Luciana C. & Rodríguez, Estefanía, 2021, Deep-Sea Anemones (Cnidaria: Anthozoa: Actiniaria) From The South Atlantic, Bulletin of the American Museum of Natural History 2021 (444), pp. 1-73 : 32

Amphianthus lacteus (McMurrich, 1893) Figures 13–14 , table 6

MATERIAL: MNRJ 8273 (4 specimens) ; locality: Projeto PIR 2 , Sta. Fasciologia Norte PIR-2, Amostrador Box core Zona 235, southwestern Atlantic , Brazil, off the coast of São Paulo, 24°49.45′ S, 44°23.02′ W, collected on 16 December 2008 by R / V F. Odyssey (no depth data). MNRJ 8284 (4 specimens) ; locality: Projeto PIR 2 , Sta. Fasciologia Sul PIR-2, Amostrador Box core Zona 235, southwestern Atlantic , Brazil, off the coast of São Paulo, 24°55.37′ S 44°27.23′ W, collected on 10 December 2008 by R / V F. Odyssey (735 m) .

MATERIAL EXAMINED: Amphianthus michaelsarsi: MZB 39191 (8 specimens, syntypes) ; locality: Michael Sars Expedition 1910, St. 53, North Atlantic Ocean, 34°59.0′ N 33°01.0′ W, collected 8 June 1920 by O. Carlgren (2615 m) .

EXTERNAL ANATOMY (fig. 13): Pedal disc flat, irregularly shaped, highly adherent, broader than column diameter, 16–21 mm in diameter in preserved specimens (fig. 13A). Column cylindrical, smooth not visibly divisible into regions (fig.

Figures

FIG. 13. External and internal anatomy and histology of Amphianthus lacteus (McMurrich, 1893). A, Lateral view of preserved specimen attached to scleractinian coral; B, oral view of preserved specimen showing tentacles; C, longitudinal section through distal column and long and narrow mesogleal sphincter musculature; note absence mesogleal basal aboral thickening of tentacle (indicated by arrow); D, cross section through tentacle and ectodermal longitudinal musculature (indicated by arrow); E, cross section through oral disc showing larvae (arrows) on oral disc and tentacles; F, cross section at actinopharynx level and single siphonoglyph; G, cross section through column at actinopharynx level and cycles of mesenteries (numbers); H, cross section through proximal column and pairs of mesenteries of second, third, and fourth cycles; I, cross

FIG. 14. Cnidom of Amphianthus lacteus (McMurrich, 1893): A, B, K, N, R, S, basitrich; C, F, L, Q, p-mastigophore B1; D, E, spirocyst; G, M, P, immature p-mastigophore B1; H–J, holotrich, O, b-mastigophore.