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A New Species of the Genus Geoemyda (Chelonii: Geoemydidae) from the Upper Pleistocene of Tokunoshima Island, the Central Ryukyus, Japan

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Abstract

Turtle fossils discovered from the putative Upper Pleistocene fissure-filling deposit on Tokunoshima Island of the Amami Group is described as a new species, Geoemyda amamiensis (Chelonii: Geoemydidae). These fossils include a carapace exclusive of peripherals and a few other elements, fragments of a neural, a costal, eight peripherals, an anterior half of the plastron, two epiplastra, and an incomplete right humerus. Geoemyda amamiensis most resembles G. japonica, an extant species endemic to three islands of the Okinawa Group, but is distinguished from the latter by the presence in dorsal view of a short anterior projection in the entoplastron. These two species seem to have split from each other through vicariance within the central Ryukyus.
Current Herpetology 26(2): 139, December 2007
2007 by The Herpetological Society of Japan
ERRATUM:A New Species of the Genus Geoemyda
(Chelonii: Geoemydidae) from the Upper Pleistocene of
Tokunoshima Island, the Central Ryukyus, Japan”, by Akio
Takahashi, Takafumi Kato, and Hidetoshi Ota,
Current Herpetology 26(1): 1–11, 2007
A recent paper describing a new fossil
Geoemyda species, G. amamiensis, has errors
in the caption of Fig. 5. The authors would
like to correct these errors as below.
Original
FIG. 5. Plastra in dorsal views of Geoemyda
amamiensis and the two extant congeneric
species. A, G. amamiensis (RUMF-GF-5011,
holotype). B, G. japonica (KUZR R62453).
C, G. spengleri (KUZ R62351). Abbreviations
are: EPI, epiplastron; ENT, entoplastron;
HYO, hyoplastron. Scale bars equal 10 mm.
Corrected
FIG. 5. Plastra in dorsal views of Geoemyda
amamiensis and the two extant congeneric
species. A, G. amamiensis (RUMF-GF-5011,
holotype). B, G. spengleri (KUZ R62351). C,
G. japonica (KUZR R62453). Abbreviations
are: EPI, epiplastron; ENT, entoplastron;
HYO, hyoplastron. Scale bars equal 10 mm.
... By comparing fossils of different ages and from different localities, detailed paleobiogeographic patterns can be developed. Keeping this advantage in mind, we have been investigating taxonomic status and phylogenetic affinities of fossil terrestrial turtles discovered from the Upper Pleistocene in the Ryukyu Archipelago by making detailed comparisons on the basis of broad material (e.g., Takahashi et al. 2003Takahashi et al. , 2007. Here, we briefly review these turtles and discuss their paleobiogeographic implications. ...
... Nevertheless, detailed Late Pleistocene Turtles of Ryukyu . Takahashi et al. morphological investigations revealed distinct differentiation of this Tokunoshima endemic from that species (Takahashi et al. 2007). ...
... Discovery of G. amamiensis from Tokunoshima Island offers another case of substantial divergence in a single clade within the central Ryukyus (Takahashi et al. 2007). This is concordant with Ota's (1998) view that the primary vicariance within this region took place between this island and the Okinawa Group. ...
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... Recently Takahashi et al. (2007) described a Late Pleistocene fossil species, Geoemyda amamiensis, from Tokunoshima, an island ca. 120 km northeast of Okinawajima Island. ...
... Recently Takahashi et al. (2007) described a Late Pleistocene fossil species, Geoemyda amamiensis, from Tokunoshima, an island ca. 120 km northeast of Okinawajima Island. ...
... Faunistically, the Ryukyu Archipelago is classified into three regions: the Northern, Central, and Southern Ryukyus (Ota, 1998). Of these, the Central Ryukyus, consisting of the Amami and Okinawa Island Groups, are noted for the high abundance of relic species in the non-volant terrestrial fauna, supposedly reflecting its consistent isolation from adjacent land masses even during the periods when the remaining islands of the Ryukyus were connected to adjacent land masses (Ota, 1998(Ota, , 2000Takahashi et al., 2007). ...
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