Научная статья на тему 'Systematics and biogeography of agamid genus Japalura in the East Asian islands'

Systematics and biogeography of agamid genus Japalura in the East Asian islands Текст научной статьи по специальности «Биологические науки»

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Ключевые слова
DISPERSAL / ISOLATION / SPECIATION / CHROMOSOMES / MITOCHONDRIAL DNA / CONSERVATION

Аннотация научной статьи по биологическим наукам, автор научной работы — Ota Hidetoshi, Honda Masanao

The agamid genus Japalura consists of 27 species and occurs from tropical to warm temperate region in the eastern half of Asia, ranging from northern India, Nepal, southern China, northern Indochina, Taiwan, and Japan. From the subtropical islands of East Asia, five morphologically poorly diverged but chromosomally and genetically distinct endemic species have been recognized Japalura polygonata, J. swinhonis, J. brevipes, J. makii, and J. luei. All these species occur in the mainland Taiwan, with partial syntopy in various combinations. Of these, only J. polygonata also occurs in the Ryukyu Archipelago of Japan and is polytypic, consisting of four subspecies J. p. xanthostoma from northern Taiwan, J. p. donan from Yonagunijima Island of the Southern Ryukyus, J. p. ishigakiensis from some other islands of the Southern Ryukyus, and J. p. polygonata from the Central Ryukyus. The karyotype consisting of 2n = 46 all telocentric chromosomes in a graded series is shared by all broadly ranging lowland (< 1,200 m asl.) populations of J. polygonata and J. swinhonis. In contrast, the remaining three species, all confined to montane habitats of mainland Taiwan (1,000 2,200 m asl.) exhibit remarkable karyotypic variations involving the chromosome number (2n = 40 in J. makii, and 36 in J. brevipes and J. luei), arm number (NF = 70 in J. makii, 46 in J. brevipes, and 52 in J. luei), and the number of size groups (two in J. brevipes, and three in J. makii and J. luei). Analyses of sequence variations in the mitochondrial 12S and 16S ribosome RNA genes supported monophyly of the three Taiwanese montane species with rather small genetic distances and their sister-group relationships to J. polygonata, leaving J. swinhonis outside. The result strongly suggests that the three montane species have recently originated through a series of speciations within Taiwan with driving forces from rapid chromosomal rearrangements. The analyses also strongly suggest an occurrence of initial divergence of J. polygonata in Taiwan and its subsequent, relatively rapid dispersals to most islands of the Ryukyu Archipelago, most likely via repetitive rafting. They further suggest that during the Late Pleistocene glacier period J. swinhonis, a species currently ranging almost throughout the lowland of Taiwan, entirely disappeared in its northern and western parts due to colder and more arid climate there, leaving surviving populations in only a few refuges of the southern and eastern parts. This also explains the absence of this quite adaptive lizard in eastern continent, which is separated from Taiwan only by fairly narrow (< 150 km) and shallow (< 100 m) Taiwan Strait. Current conservation status of the East Asian Japalura populations is also briefly reviewed with a discussion of desirable conservation measures.

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Текст научной работы на тему «Systematics and biogeography of agamid genus Japalura in the East Asian islands»

DeAgamis2: 2nd INTERNATIONAL SYMPOSIUM ON AGAMID LIZARDS

BARCODING AGAMID LIZARDS OF VIETNAM

R.W. Murphy 1 2, J. Che 1, J.Q. Jin 1, F.B. Grazziotin 3, S.N. Nguyen 1, H. Zaher 3, N.L. Orlov 4, N.B. Ananjeva 4, and Y.P. Zhang 1

1 State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology,

Chinese Academy of Sciences Kunming 650223, P.R. China E-mail: [email protected], [email protected], [email protected], [email protected], [email protected] 2 Centre for Biodiversity and Conservation Biology, Royal Ontario Museum 100 Queen's Park, Toronto, Ont., CanadaM5S 2C6 E-mail: [email protected] 3 Museu de Zoologia, Universidade de Sao Paulo Caixa Postal 42.494, 04218-970, Sao Paulo, Sp, Brasil E-mail: [email protected], [email protected] 4 Zoological Institute, Russian Academy of Sciences 1 Universitetskaya nab., St. Petersburg 199034, Russia E-mail: [email protected]

The age of genomics has now arrived. It is feasible to gather the complete genomes of most vertebrate species. Because this effort requires a significant amount of both time and money, species identification is critical in order to avoid the innumerable errors present in online databases, such as GenBank. Agamid lizards, which are a major component of the Squamata, often form a dominant component of the herpetofauna throughout their range. Being diurnal, many species are commonly encountered by local residents. Some species are used as food and maintained as pets, yet others are rarely encountered owing to arboreality and crypsis.

We undertook a barcoding analysis of species and populations in Vietnam while using global representative taxa. We surveyed about 120 species representing seven genera, and multiple populations

of species occurring in Vietnam. Intergeneric divergence was usually sufficient to unambiguously assign unknown samples to genera. Within genera containing multiple species, interspecific divergence allowed the correct identification of species. Intras-pecific divergence was significant in some species indicating the possibility of multiple cryptic species. The analysis also detected misidentified specimens and museum cataloging errors, which would be critical to resolve before pursuing whole genome analyses.

The analysis indicated taxa requiring further investigation, while also finding those that exhibit very little genetic variation throughout the range of sampling.

Key words: Barcoding, Genome 10K, Vietnam; China.

SYSTEMATICS AND BIOGEOGRAPHY OF AGAMID GENUS JAPALURA IN THE EAST ASIAN ISLANDS

Hidetoshi Ota and Masanao Honda

Institute of Natural and Environmental Sciences, University of Hyogo Sanda, Hyogo 669-1546, Japan E-mail: [email protected]

The agamid genus Japalura consists of 27 species and occurs from tropical to warm temperate region in the eastern half of Asia, ranging from

northern India, Nepal, southern China, northern Indochina, Taiwan, and Japan. From the subtropical islands of East Asia, five morphologically poorly

COBPEMEHHA3 TEPnETO.nOrHtf 2010 T. 10, Bbm. 3/4

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DeAgamis2: ВТОРОЙ МЕЖДУНАРОДНЫЙ СИМПОЗИУМ ПО АГАМОВЫМ ЯЩЕРИЦАМ

diverged but chromosomally and genetically distinct endemic species have been recognized - Japalura polygonata, J. swinhonis, J. brevipes, J. makii, and J. luei. All these species occur in the mainland Taiwan, with partial syntopy in various combinations. Of these, only J. polygonata also occurs in the Ryu-kyu Archipelago of Japan and is polytypic, consisting of four subspecies - J. p. xanthostoma from northern Taiwan, J. p. donan from Yonagunijima Island of the Southern Ryukyus, J. p. ishigakiensis from some other islands of the Southern Ryukyus, and J. p. polygonata from the Central Ryukyus. The karyotype consisting of 2n = 46 all telocentric chromosomes in a graded series is shared by all broadly ranging lowland (< 1,200 m asl.) populations of J. polygonata and J. swinhonis. In contrast, the remaining three species, all confined to montane habitats of mainland Taiwan (1,000 - 2,200 m asl.) exhibit remarkable karyotypic variations involving the chromosome number (2n = 40 in J. makii, and 36 in J. brevipes and J. luei), arm number (NF = 70 in J. makii, 46 in J. brevipes, and 52 in J. luei), and the number of size groups (two in J. brevipes, and three in J. makii and J. luei). Analyses of sequence variations in the mitochondrial 12S and 16S ribo-some RNA genes supported monophyly of the three

Taiwanese montane species with rather small genetic distances and their sister-group relationships to J. polygonata, leaving J. swinhonis outside. The result strongly suggests that the three montane species have recently originated through a series of specia-tions within Taiwan with driving forces from rapid chromosomal rearrangements. The analyses also strongly suggest an occurrence of initial divergence of J. polygonata in Taiwan and its subsequent, relatively rapid dispersals to most islands of the Ryukyu Archipelago, most likely via repetitive rafting. They further suggest that during the Late Pleistocene glacier period J. swinhonis, a species currently ranging almost throughout the lowland of Taiwan, entirely disappeared in its northern and western parts due to colder and more arid climate there, leaving surviving populations in only a few refuges of the southern and eastern parts. This also explains the absence of this quite adaptive lizard in eastern continent, which is separated from Taiwan only by fairly narrow (< 150 km) and shallow (< 100 m) Taiwan Strait. Current conservation status of the East Asian Japalura populations is also briefly reviewed with a discussion of desirable conservation measures.

Key words: dispersal, isolation, speciation, chromosomes, mitochondrial DNA, conservation.

MOLECULAR PHYLOGENY AND INTRASPECIFIC DIFFERENTIATION OF THE IRANIAN AND CENTRAL ASIAN SPECIES IN THE GENUS TRAPELUS (SAURIA: AGAMIDAE) INFERRED FROM MITOCHONDRIAL DNA SEQUENCES

Eskandar Rastegar-Pouyani l, Nasrullah Rastegar-Pouyani 2, Ulrich Joger 3, and Michael Wink 4

1 Department of Biology, Sabzevar Tarbiat Moalem University PO Box 397 Sabzevar, Iran E-mail: [email protected]

2 Department of Biology, Faculty of Science, Razi University Kermanshah 67149, Iran

3 State Natural History Museum 10 Pockels Str., Braunschweig 38106, Germany

4 Institute ofPharmacy and Molecular Biotechnology, Department of Biology, University of Heidelberg Im Neuenheimer Feld 364, D-69120 Heidelberg, Germany

The steppe agamas of the genus Trapelus Cu-vier, 1816, are an old clade of agamid lizards with an Afro-Arabian origin. The genus consists of about 14 - 15 species which are distributed from northwestern Africa, along the Saharan border, through the Near East to southwest and central Asia. They

constitute one of the major components of the Iranian Plateau and central Asian fauna and are highly adapted to steppe, semi-deserts and desert environments. To date, published morphological and molecular phylogenetic hypotheses of Trapelus are only partially congruent, and the relationships

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СОВРЕМЕННАЯ ГЕРПЕТОЛОГИЯ 2010 Т. 10, вып. 3/4

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