Significance of diadematid echinoid ossicles in micropalaeontological samples, Miocene–Pliocene of Indonesia

Abstract

Fragments of diadematoid echinoids from the early and middle Miocene, and late Miocene–Pliocene, respectively, of Java, Kalimantan and Sulawesi, Indonesia, are identified as diadematid spp. indet. (radioles from all sites) and Centrostephanus sp. (an interambulacral plate; early Miocene, Java). The radioles are probably a mixture of Diadema ± Centrostephanus ± Echinothrix. This is the first report of identifiable fossil diadematoid remains from Indonesia and demonstrates that these echinoids, so common in modern reef environments, were present in the Neogene of the region. Even though classified in open nomenclature, Centrostephanus sp. nevertheless provides further evidence for the Cenozoic record of a genus in which the only nominal species are of Late Cretaceous and Holocene age.

Key words:

• Sulawesi
• Kalimantan
• Java
• radioles
• Centrostephanus
• Neogene

Acknowledgements

We thank Dr Charlotte Jeffery (University of Liverpool) for her early interest in this project. Dr Andreas Kroh (Natural History Museum Vienna) kindly commented on an early version of this paper. Constructive reviews by Mr David N. Lewis (The Natural History Museum, London) and Dr Dinesh Srivastava (University of Lucknow) are gratefully acknowledged.