Reproductive biology and early life history of the hermaphroditic feather star Dorometra sesokonis (Echinodermata: Crinoidea)

• Published in: Marine biology Vol. 157; no. 6; pp. 1191 - 1201
• Main Authors: Obuchi, Masami, Fujita, Yoshihisa, Nakano, Yoshikatsu, Uehara, Tsuyoshi, Motokawa, Tatsuo
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.06.2010; Springer-Verlag; Springer; Springer Nature B.V
• Subjects: adults; Animal and plant ecology; animal ovaries; Animal reproduction; Animal, plant and microbial ecology; Biological and medical sciences; Biomedical and Life Sciences; breeding; brooders; Colleges & universities; Coral reefs; Crinoidea; Echinodermata; Freshwater & Marine Ecology; Fundamental and applied biological sciences. Psychology; Hatching; Invertebrates; Larvae; Larval development; Life history; Life Sciences; Marine; Marine & Freshwater Sciences; Marine biology; Microbiology; Oceanography; Original Paper; Physiological aspects; Population density; postlarvae; Ryukyu Archipelago; Sea water ecosystems; Synecology; testes; Zoology; Japan; Ryukyu Archipelago; Japan, Nansei-shoto, Okinawa; Japan, Nansei-shoto, Okinawa, Okinawa-shoto Is., Okinawa I., Sesoko-jima I; Reef Slope; Attachment Disk; Ciliated Band; Oral Plate; Simultaneous Hermaphrodite; Life history; Reproduction; Echinodermata; Biology; Invertebrata; Crinoidea; Hermaphrodite
• ISSN: 0025-3162; 1432-1793
• DOI: 10.1007/s00227-010-1399-3

Reproduction and larval/post-larval development of the one of the smallest known comatulid Dorometra sesokonis were studied on the coral reefs of Sesoko-jima Island, Okinawa, Japan. Breeding individuals were found every month from May 2003 to April 2004 indicating continuous reproduction. Individuals possessed both mature ovaries and testes, and were therefore characterized as simultaneous hermaphrodites. This species was observed to be an external brooder in which the embryos developed on the surface of parental genital pinnules until the doliolaria larval stage, and subsequently released doliolariae settled on substrata within 4 days after hatching. Larvae then metamorphosed into the post-larval cystidean stage, which lasted for more than a month. The reproductive features of this species are unique among crinoids, and, together with juvenile morphological features observed in adults, can be interpreted as adaptations to their cryptic habitat, which is subject to frequent natural disturbances.