Non-destructive morphological observations of the fleshy brittle star, Asteronyx loveni using micro-computed tomography (Echinodermata, Ophiuroidea, Euryalida)

By

Okanishi, Massanori
Fujita, Toshihiko, 1961-
Maekawa, Yu
Sasaki, Takenori

Type

Article

Date of Publication

2017

Original Publication

ZooKeys

Volume

663

Pages

1-19

Subjects

Anatomy , Asteronychidae , computed tomography , Euryalida , soft tissue , taxonomy

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.663.11413

 

Abstract

The first morphological observation of a euryalid brittle star, Asteronyx loveni, using non-destructive X-ray micro-computed tomography (µCT) was performed. The body of euryalids is covered by thick skin, and it is very difficult to observe the ossicles without dissolving the skin. Computed tomography with micrometer resolution (approximately 4.5–15.4 µm) was used to construct 3D images of skeletal ossicles and soft tissues in the ophiuroid’s body. Shape and positional arrangement of taxonomically important ossicles were clearly observed without any damage to the body. Detailed pathways inside the vertebral ossicles, lateral arm plates, and arm spines for passage of nerves and water vascular structures were observed. Inter-vertebral muscles were also observed. Forms and 3D arrangements of many important taxonomical characters of the euryalids were scrutinized by µCT in high enough resolution for taxonomic description of ophiuroids.