BB25, Bakam Beach (Pleistocene of Malaysia)

Where: Sarawak, Malaysia (4.2° N, 113.9° E: paleocoordinates 4.2° N, 113.9° E)

• coordinate estimated from map

When: Pleistocene (2.6 - 0.0 Ma)

• Written as: ?Pleistocene formation, unknown.The sediment from which the crabs are derived has yet to be identified in the Miri area. However, the Pliocene Liang Formation (discussed below) is unconformably overlain by Pleistocene alluvia of clays, sands and conglomerates which have yielded fossilised crabs of the genera Macrophthalmus sp. and Charybdis sp. in Brunei (Wilford 1961: 109, 153). Macrophthalmus and Scylla sp. have also been collected from Pleistocene alluvia in Sabah (Idris 1989). By inference, the fossil crabs from Bakam beach could well have been derived from Pleistocene alluvia now submerged in the sea.

Environment/lithology: marine; lithified, concretionary lithology not reported

• Written as: Tidal flat to shallow marine
• written as: Wave transported beach debris

Size class: macrofossils

Primary reference: J. S. H. Collins, C. Lee, and J. Noad. 2003. Miocene and Pleistocene Crabs (Crustacea, Decapoda) from Sabah and Sarawak. Journal of Systematic Palaentology 1:187-226 [C. Schweitzer/L. Baltzly/M. Clapham]more details

Purpose of describing collection: taxonomic analysis

PaleoDB collection 175180: authorized by Carrie Schweitzer, entered by Lerin Baltzly on 04.12.2015, edited by Matthew Clapham

Creative Commons license: CC BY (attribution)

Taxonomic list

Malacostraca
 Decapoda - Galenidae
Galene obscura Milne-Edwards 1865 crab
 Decapoda - Pilumnidae
"Galene litoralis n. sp." = Cryptolutea litoralis
"Galene litoralis n. sp." = Cryptolutea litoralis Collins et al. 2003 crab
 Decapoda - Epialtidae
Pisoides cf. bidentatus Milne-Edwards 1873 spider crab
 Decapoda - Portunidae
"Charybdis (Charybdis) cf. annulata" = Charybdis annulata, Podophthalmus vigil
"Charybdis (Charybdis) cf. annulata" = Charybdis annulata Fabricius 1798 swimming crab
Podophthalmus vigil Fabricius 1798 periscope crab
 Decapoda - Xanthidae
Cyclodius ungulatus Milne-Edwards 1834 stone crab
 Decapoda - Macrophthalmidae
Macrophthalmus (Mareotis) wilfordi Morris and Collins 1991 crab