The extinct river shark Glyphis pagoda from the Miocene of Myanmar and a review of the fossil record of the genus Glyphis (Carcharhiniformes

Carcharhinidae)

Kenshu Shimada, Naoko Egi, Takehisa Tsubamoto, Maung-Maung, Thaung-Htike, Zin-Maung-Maung-Thein, Yuichiro Nishioka, Teppei Sonoda, Masanaru Takai

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

We redescribe an extinct river shark, Glyphis pagoda (Noetling), on the basis of 20 teeth newly collected from three dif-ferent Miocene localities in Myanmar. One locality is a nearshore marine deposit (Obogon Formation) whereas the other two localities represent terrestrial freshwater deposits (Irrawaddy sediments), suggesting that G. pagoda from the Irrawad-dy sediments was capable of tolerating low salinity like the extant Glyphis. Glyphis pagoda likely reached up to at least 185 cm in total body length and was probably piscivorous. The fossil species occurs in rocks of Myanmar and eastern and western India and stratigraphically ranges at least from the Lower Miocene (Aquitanian) to the lower Upper Miocene (mid-Tortonian). It has been classified under at least eight other genera to date, along with numerous taxonomic synonyms largely stemming from the lack of understanding of the heterodonty in extant Glyphis in the original description. Our lit-erature review suggests that known Miocene shark faunas, particularly those in India, are manifested with unreliable tax-onomic identifications and outdated classifications that warrant the need for a comprehensive taxonomic review in order to evaluate the evolutionary history and diversity pattern of Miocene shark faunas. The genus Glyphis has a roughly 23- million-year-long history, and its success may be related to the evolution of its low salinity tolerance. While extant Glyphis spp. are considered to be particularly vulnerable to habitat degradation and overfishing, the fossil record of G. pa-goda provides renewed perspective on the natural history of the genus that can be taken into further consideration for con-servation biology of the extant forms.

Original languageEnglish
Pages (from-to)237-251
Number of pages15
JournalZootaxa
Volume4161
Issue number2
DOIs
Publication statusPublished - 2016 Sep 5

Fingerprint

Carcharhiniformes
Carcharhinidae
Myanmar
shark
sharks
fossil record
fossils
Miocene
rivers
river
fauna
salinity
India
sediments
history
overfishing
taxes
natural history
body length
teeth

Keywords

  • Chondrichthyes
  • Elasmobranchii
  • Fossil
  • Irrawaddy sediments
  • Obogon format

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Animal Science and Zoology

Cite this

The extinct river shark Glyphis pagoda from the Miocene of Myanmar and a review of the fossil record of the genus Glyphis (Carcharhiniformes : Carcharhinidae). / Shimada, Kenshu; Egi, Naoko; Tsubamoto, Takehisa; Maung-Maung; Thaung-Htike; Zin-Maung-Maung-Thein; Nishioka, Yuichiro; Sonoda, Teppei; Takai, Masanaru.

In: Zootaxa, Vol. 4161, No. 2, 05.09.2016, p. 237-251.

Research output: Contribution to journalArticle

Shimada, K, Egi, N, Tsubamoto, T, Maung-Maung, Thaung-Htike, Zin-Maung-Maung-Thein, Nishioka, Y, Sonoda, T & Takai, M 2016, 'The extinct river shark Glyphis pagoda from the Miocene of Myanmar and a review of the fossil record of the genus Glyphis (Carcharhiniformes: Carcharhinidae)', Zootaxa, vol. 4161, no. 2, pp. 237-251. https://doi.org/10.11646/zootaxa.4161.2.6
Shimada, Kenshu ; Egi, Naoko ; Tsubamoto, Takehisa ; Maung-Maung ; Thaung-Htike ; Zin-Maung-Maung-Thein ; Nishioka, Yuichiro ; Sonoda, Teppei ; Takai, Masanaru. / The extinct river shark Glyphis pagoda from the Miocene of Myanmar and a review of the fossil record of the genus Glyphis (Carcharhiniformes : Carcharhinidae). In: Zootaxa. 2016 ; Vol. 4161, No. 2. pp. 237-251.
@article{58856ee3d7b24cdf9c9edacd5cd2db7a,
title = "The extinct river shark Glyphis pagoda from the Miocene of Myanmar and a review of the fossil record of the genus Glyphis (Carcharhiniformes: Carcharhinidae)",
abstract = "We redescribe an extinct river shark, Glyphis pagoda (Noetling), on the basis of 20 teeth newly collected from three dif-ferent Miocene localities in Myanmar. One locality is a nearshore marine deposit (Obogon Formation) whereas the other two localities represent terrestrial freshwater deposits (Irrawaddy sediments), suggesting that G. pagoda from the Irrawad-dy sediments was capable of tolerating low salinity like the extant Glyphis. Glyphis pagoda likely reached up to at least 185 cm in total body length and was probably piscivorous. The fossil species occurs in rocks of Myanmar and eastern and western India and stratigraphically ranges at least from the Lower Miocene (Aquitanian) to the lower Upper Miocene (mid-Tortonian). It has been classified under at least eight other genera to date, along with numerous taxonomic synonyms largely stemming from the lack of understanding of the heterodonty in extant Glyphis in the original description. Our lit-erature review suggests that known Miocene shark faunas, particularly those in India, are manifested with unreliable tax-onomic identifications and outdated classifications that warrant the need for a comprehensive taxonomic review in order to evaluate the evolutionary history and diversity pattern of Miocene shark faunas. The genus Glyphis has a roughly 23- million-year-long history, and its success may be related to the evolution of its low salinity tolerance. While extant Glyphis spp. are considered to be particularly vulnerable to habitat degradation and overfishing, the fossil record of G. pa-goda provides renewed perspective on the natural history of the genus that can be taken into further consideration for con-servation biology of the extant forms.",
keywords = "Chondrichthyes, Elasmobranchii, Fossil, Irrawaddy sediments, Obogon format",
author = "Kenshu Shimada and Naoko Egi and Takehisa Tsubamoto and Maung-Maung and Thaung-Htike and Zin-Maung-Maung-Thein and Yuichiro Nishioka and Teppei Sonoda and Masanaru Takai",
year = "2016",
month = "9",
day = "5",
doi = "10.11646/zootaxa.4161.2.6",
language = "English",
volume = "4161",
pages = "237--251",
journal = "Zootaxa",
issn = "1175-5326",
publisher = "Magnolia Press",
number = "2",

}

TY - JOUR

T1 - The extinct river shark Glyphis pagoda from the Miocene of Myanmar and a review of the fossil record of the genus Glyphis (Carcharhiniformes

T2 - Carcharhinidae)

AU - Shimada, Kenshu

AU - Egi, Naoko

AU - Tsubamoto, Takehisa

AU - Maung-Maung,

AU - Thaung-Htike,

AU - Zin-Maung-Maung-Thein,

AU - Nishioka, Yuichiro

AU - Sonoda, Teppei

AU - Takai, Masanaru

PY - 2016/9/5

Y1 - 2016/9/5

N2 - We redescribe an extinct river shark, Glyphis pagoda (Noetling), on the basis of 20 teeth newly collected from three dif-ferent Miocene localities in Myanmar. One locality is a nearshore marine deposit (Obogon Formation) whereas the other two localities represent terrestrial freshwater deposits (Irrawaddy sediments), suggesting that G. pagoda from the Irrawad-dy sediments was capable of tolerating low salinity like the extant Glyphis. Glyphis pagoda likely reached up to at least 185 cm in total body length and was probably piscivorous. The fossil species occurs in rocks of Myanmar and eastern and western India and stratigraphically ranges at least from the Lower Miocene (Aquitanian) to the lower Upper Miocene (mid-Tortonian). It has been classified under at least eight other genera to date, along with numerous taxonomic synonyms largely stemming from the lack of understanding of the heterodonty in extant Glyphis in the original description. Our lit-erature review suggests that known Miocene shark faunas, particularly those in India, are manifested with unreliable tax-onomic identifications and outdated classifications that warrant the need for a comprehensive taxonomic review in order to evaluate the evolutionary history and diversity pattern of Miocene shark faunas. The genus Glyphis has a roughly 23- million-year-long history, and its success may be related to the evolution of its low salinity tolerance. While extant Glyphis spp. are considered to be particularly vulnerable to habitat degradation and overfishing, the fossil record of G. pa-goda provides renewed perspective on the natural history of the genus that can be taken into further consideration for con-servation biology of the extant forms.

AB - We redescribe an extinct river shark, Glyphis pagoda (Noetling), on the basis of 20 teeth newly collected from three dif-ferent Miocene localities in Myanmar. One locality is a nearshore marine deposit (Obogon Formation) whereas the other two localities represent terrestrial freshwater deposits (Irrawaddy sediments), suggesting that G. pagoda from the Irrawad-dy sediments was capable of tolerating low salinity like the extant Glyphis. Glyphis pagoda likely reached up to at least 185 cm in total body length and was probably piscivorous. The fossil species occurs in rocks of Myanmar and eastern and western India and stratigraphically ranges at least from the Lower Miocene (Aquitanian) to the lower Upper Miocene (mid-Tortonian). It has been classified under at least eight other genera to date, along with numerous taxonomic synonyms largely stemming from the lack of understanding of the heterodonty in extant Glyphis in the original description. Our lit-erature review suggests that known Miocene shark faunas, particularly those in India, are manifested with unreliable tax-onomic identifications and outdated classifications that warrant the need for a comprehensive taxonomic review in order to evaluate the evolutionary history and diversity pattern of Miocene shark faunas. The genus Glyphis has a roughly 23- million-year-long history, and its success may be related to the evolution of its low salinity tolerance. While extant Glyphis spp. are considered to be particularly vulnerable to habitat degradation and overfishing, the fossil record of G. pa-goda provides renewed perspective on the natural history of the genus that can be taken into further consideration for con-servation biology of the extant forms.

KW - Chondrichthyes

KW - Elasmobranchii

KW - Fossil

KW - Irrawaddy sediments

KW - Obogon format

UR - http://www.scopus.com/inward/record.url?scp=84985993077&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84985993077&partnerID=8YFLogxK

U2 - 10.11646/zootaxa.4161.2.6

DO - 10.11646/zootaxa.4161.2.6

M3 - Article

VL - 4161

SP - 237

EP - 251

JO - Zootaxa

JF - Zootaxa

SN - 1175-5326

IS - 2

ER -