Pantestuguria

 Indian pond turtles Melanochelys trijuga, photographed by Manoj Sindagi.

Belongs within: Centrocryptodira.
Contains: Batagurinae, Testudinidae, Geoemyda.

The Testudinoidae is a proposed clade uniting the land tortoises of the Testudinidae with the Asian pond turtles of the paraphyletic ‘Bataguridae’. The monophyly of this clade is unsettled, as proposed synapomorphies are also found in other testudinates, and are not universal within testudinoidaens (Gaffney & Meylan 1988).

Pond turtles of Asia
Published 30 August 2018

In an earlier post on this site, I discussed some members of the tortoise family Testudinidae. In popular depictions, the terrestrial tortoises are commonly associated with arid deserts and Mediterranean climes, where rains are sparse and water bodies few. But tortoises are exceptional in this regard among the order Testudines, members of which are more generally aquatic. As an example, consider the closest relatives of the Testudinidae, the pond turtles of the Geoemydidae.

Southern river terrapin Batagur affinis, copyright Eng Heng Chan.

Members of the Geoemydidae (historically referred to in many publications as the Bataguridae) are commonly referred to as the Asiatic pond turtles and it is in southern and eastern Asia that they are most diverse. However, they are also found in Europe and northern Africa, and a single genus Rhinoclemmys is found in northern South America. About 65 or 70 species are recognised in the family, making them quite diverse as turtles go. Many geoemydids are colorfully patterned and some can reach reasonably large sizes. The northern river terrapin Batagur baska, for instance, may grow up to two feet in length and close to twenty kilograms in weight.

Black-breasted leaf turtle Geoemyda spengleri, copyright Heather Paul.

A phylogenetic analysis of the Geoemydidae by Hirayama in 1984 lead to the suggested division of the geoemydids between two subfamilies, the Geoemydinae and Batagurinae. The two subfamilies were primarily distinguished by the extent of development of the secondary palate and hence the width of their jaws, with the Batagurinae having a more extensive secondary palate and broader jaws than the Geoemydinae. Batagurines were also generally more aquatic and more herbivorous than the semi-terrestrial, more omnivorous geoemydines. Hirayama also suggested that the geoemydines might be paraphyletic to the Testudinidae (Spinks et al. 2004). More recent phylogenetic analyses have supported geoemydid monophyly, placing them as sister rather than ancestral to Testudinidae (Spinks et al. 2004; Guillon et al. 2012). They have also supported a clade including the majority of Hirayama’s batagurines, excluding only the genus Siebenrockiella. However, Hirayama’s geoemydines have not been supported as monophyletic; instead, the Neotropical Rhinoclemmys represents the sister group of the Old World geoemydids. This is not entirely surprising; comparison with other turtle families indicates that the narrow-jawed ‘geoemydine’ condition is primitive among turtles. As a result, the Batagurinae is no longer recognised as a distinct subfamily.

Golden coin turtle Cuora trifasciata, copyright Torsten Blanck.

Unfortunately, the Asian species of pond turtle are currently facing a conservational crisis. The majority of species are regarded as endangered, many critically so, due to threats such as habitat loss and hunting for food. Some species, most notably the golden coin turtle Cuora trifasciata, are targeted for use in Chinese medicine because why wouldn’t they be? Many geoemydid species have been bred in captivity but this is also not without issues. In the case of the golden coin turtle, there is the all-too-common issue that even when farmed individuals are available they are not seen as being as valuable as wild-caught specimens. Also, because the gender of hatchlings is determined by incubation temperature, farmed clutches are skewed almost entirely towards females, requiring the continued harvesting of wild males. Many geoemydid species hybridise readily. During the period from 1984 to 1997, no less than thirteen new species of geoemydid were described from China, most on the basis of specimens purchased from a single pet dealer in Hong Kong (Parham et al. 2001). Many of these specimens were of uncertain origin. Searches for further specimens in reported localities for some species failed to provide results, and queries to local residents revealed that they had never seen such turtles. At least some of these supposed new species have since been identified as hybrids, probably produced in captivity, and the status of others remains questionable.

Systematics of Pantestuguria

Synapomorphies (from Gaffney & Meylan 1988, for Testudinoidae): (Including Echmatemys) Axillary and inguinal musk duct foramina enclosed within peripheral plates or between peripherals and plastral buttresses. (Excluding Echmatemys) Sixth marginal scute often reaching third pleural scute; postorbital-squamosal contact absent.

<==Pantestuguria [Bataguridae, Geoemydidae, Panbataguridae, Testudinoidae]JPG04
    |  i. s.: Annamemys annamensisCP03
    |         Leucocephalon yuwonoi (McCord, Iverson & Boeadi 1995)JPG04
    |         PangshuraJPG04
    |           |--P. smithii (Gray 1863)JPG04
    |           |--P. sylhetensis Jerdon 1870JPG04
    |           |--P. tecta (Gray 1831)JPG04
    |           `--P. tentoria (Gray 1834)JPG04
    |         PtychogastriniH96
    |--Echmatemys Hay 1906GM88, H96
    |    |--E. septariaSP96
    |    `--E. testudinea (Cope 1872)B93
    `--TestuguriaJPG04
         |--BatagurinaeGM88
         `--GeoemydinaeGM88
              |  i. s.: RhinoclemmysGM88
              |           |--R. annulata (Gray 1860)JPG04
              |           |--R. areolata (Duméril & Bibron 1851)JPG04
              |           |--R. diademata (Mertens 1954)JPG04
              |           |--R. funerea (Cope 1876)JPG04
              |           |--R. melanosterna (Gray 1861)JPG04
              |           |--R. nasuta (Boulenger 1902)JPG04
              |           |--R. pulcherrima (Gray 1855)JPG04
              |           |--R. punctularia (Daudin 1801)JPG04
              |           `--R. rubida (Cope 1870)JPG04
              |--MauremysGM88
              |    |--M. annamensis (Siebenrock 1903)JPG04
              |    |--M. caspica (Gmelin 1774)JPG04
              |    |--M. japonica (Temmick & Schlegel 1835)JPG04
              |    |--M. leprosa (Schweigger 1812)JPG04
              |    |--M. mutica (Cantor 1842)JPG04
              |    |--M. nigricans (Gray 1834)JPG04
              |    |--M. reevesii (Gray 1831)JPG04
              |    `--M. sinensis (Gray 1834)JPG04
              `--+--+--Notochelys platynota (Gray 1834)GM88, JPG04
                 |  `--SacaliaGM88
                 |       |--S. bealei (Gray 1831)JPG04
                 |       `--S. quadriocellata Siebenrock 1903JPG04
                 `--+--+--HeosemysGM88
                    |  |    |--H. depressa (Anderson 1875)JPG04
                    |  |    |--H. grandis (Gray 1860)JPG04
                    |  |    |--H. leytensis Taylor 1920JPG04
                    |  |    `--H. spinosa (Gray 1831)JPG04
                    |  `--CyclemysGM88
                    |       |--C. dentata (Gray 1831)JPG04
                    |       |--C. oldhamii Gray 1863JPG04
                    |       |--C. pulchristriata Fritz, Gaulke & Leh 1997JPG04 [incl. C. atripons Iverson & McCord 1997D03]
                    |       `--C. tcheponensis (Bourret 1939)JPG04
                    `--+--MelanochelysGM88
                       |    |--M. tricarinata (Blyth 1856)JPG04
                       |    `--M. trijuga (Schweigger 1812)JPG04
                       `--+--+--TestudinidaeGM88
                          |  `--+--CistoclemmysGM88
                          |     |    |--C. flavomarginataGM88
                          |     |    `--C. galbinifronsGM88
                          |     `--+--GeoemydaGM88
                          |        `--Pyxidea mouhotiiGM88, CP03
                          `--CuoraGM88
                               |--C. amboinensis (Daudin 1802)JPG04
                               |--C. aurocapitata Luo & Zong 1988JPG04
                               |--C. bourreti Obst & Reimann 1994JPG04
                               |--C. flavomarginata (Gray 1863)I92
                               |--C. galbinifrons Bourret 1939JPG04
                               |--C. mccordi Ernst 1988D03
                               |--C. mouhotii (Gray 1862)JPG04
                               |--C. pani Song 1984JPG04 [incl. C. chriskarannarum Ernst & McCord 1987D03]
                               |--C. picturata Lehr, Fritz & Obst 1998JPG04
                               |--C. trifasciata (Bell 1825)JPG04
                               |--C. yunnanensis (Boulenger 1906)JPG04
                               `--C. zhoui Zhao 1990JPG04 [incl. C. pallidicephala McCord & Iverson 1991D03]
Hybrids: Cuora serrata Iverson & McCord 1992 [Pyxidea mouhotii × Cuora galbinifrons]D03
         Mauremys iversoni Pritchard & McCord 1991 [M. mutica × Cuora trifasciata]D03
         Mauremys pritchardi McCord 1997 [M. mutica × Chinemys reevesii]D03
         Sacalia pseudocellata Iverson & McCord 1992 [Cuora trifasciata × S. quadriocellata]D03

*Type species of generic name indicated

References

[B93] Benton, M. J. 1993. Reptilia. In: Benton, M. J. (ed.) The Fossil Record 2 pp. 681–715. Chapman & Hall: London.

[CP03] Claude, J., E. Paradis, H. Tong & J.-C. Auffray. 2003. A geometric morphometric assessment of the effects of environment and cladogenesis on the evolution of the turtle shell. Biological Journal of the Linnean Society 79: 485–501.

[D03] Dalton, R. 2003. Mock turtles. Nature 423: 219–220.

[GM88] Gaffney, E. S., & P. A. Meylan. 1988. A phylogeny of turtles. In: Benton, M. J. (ed.) The Phylogeny and Classification of the Tetrapods vol. 1. Amphibians, Reptiles, Birds pp. 157–219. Clarendon Press: Oxford.

Guillon, J.-M., L. Guéry, V. Hulin & M. Girondot. 2012. A large phylogeny of turtles (Testudines) using molecular data. Contributions to Zoology 81 (3): 147–158.

[H96] Hutchison, J. H. 1996. Testudines. In: Prothero, D. R., & R. J. Emry (eds) The Terrestrial Eocene–Oligocene Transition in North America pp. 337–353. Cambridge University Press.

[I92] Iwahashi, J. (ed.) 1992. Reddo Deeta Animaruzu: a pictorial of Japanese fauna facing extinction. JICC: Tokyo.

[JPG04] Joyce, W. G., J. F. Parham & J. A. Gauthier. 2004. Developing a protocol for the conversion of rank-based taxon names to phylogenetically defined clade names, as exemplified by turtles. Journal of Paleontology 78 (5): 989–1013.

Parham, J. F., W. B. Simison, K. H. Kozak, C. R. Feldman & H. Shi. 2001. New Chinese turtles: endangered or invalid? A reassessment of two species using mitochondrial DNA, allozyme electrophoresis and known-locality specimens. Animal Conservation 4: 357–367.

Spinks, P. Q., H. B. Shaffer, J. B. Iverson & W. P. McCord. 2004. Phylogenetic hypotheses for the turtle family Geoemydidae. Molecular Phylogenetics and Evolution 32: 164–182.

[SP96] Stucky, R. K., D. R. Prothero, W. G. Lohr & J. R. Snyder. 1996. Magnetic stratigraphy, sedimentology, and mammalian faunas of the Early Uintan Washakie Formation, Sand Wash Bain, northwestern Colorado. In: Prothero, D. R., & R. J. Emry (eds) The Terrestrial Eocene–Oligocene Transition in North America pp. 40–51. Cambridge University Press.

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