Genetics differentiation and systematic of peripheral populations of East Asian endemic rodent Myospalax psilurus (Rodentia, Spalacidae)

M.V. Tsvirka, M.V. Pavlenko, V.P. Korablev

Institute of Biology and Soil Science FEB RAS Vladivostok, 690022, Russia 2013

PROBLEMS

subfamily Myospalacinae

: endemic in the Eastern Asia taxonomy and evolution are not well studied 6-10 recognized species one (

Myospalax

) or two (

Myospalax

and

Eospalax

) genera Fan, Shi, 1982; Musser, Carleton, 2005

M. myospalax

PROBLEMS

M. aspalax M. armandii M. psilurus

• • • L. Martynova, N. Vorontsov,

1975.

Population cytogenetic of Zokors Chromosomes L. Martynova,

1976.

Chromosomal differentiation of three species of zokors.

L. Martynova, I. Fomicheva, N. Vorontsov,

1977.

zokors.

Electrophoretic study of blood protein of

PROBLEMS

M. psilurus

MAIN GOAL, METHODS, MATERIALS

- to clarify the genetic differences among two peripheral populations of the Manchurian zokors - to resolve the systematic position of

M. psilurus

from Khanka Plain and

M. epsilanus

from Transbaikalia - 45 specimens of the Manchurian zokors were studied from 12 localities : - 27 from Khanka Plain -18 from Transbaikalia by allozyme, karyological and molecular-genetic methods :RAPD- analysis, sequencing of two mt DNA fragments CR (518 bp) and cyt b (1141 bp)

MAIN GOAL, METHODS, MATERIALS

Study area and localities of Manchurian zokor

M. psilurus

RESULTS

Myospalax psilurus,

Primorye, 2n=64 (9-12 M-SM, 10-13 ST, 8-A)

Myospalax epsilanu

s, Transbaikalia, 2n=64 (9 M-SM, 13-14 ST, 8-9 A)

1. Tf-A - Myospalax aspalax 2. Tf-B Myospalax psilurus, Primorye 3. Tf-C Myospalax epsilanus, Transbaikalia 4. Tf-C1 - Myospalax armandii 5. Tf-D - Myospalax myospalax

RESULTS

1-3

Myospalax epsilanu

s, Transbaikalia

4-5 Myospalax psilurus,

Primorye RAPD-marker fragments and position of studied populations on the UPGMA (a) and MST (b) trees

NJ cyt b 1141 bp

RESULTS

Myospalax psilurus

Primorye territory 2N=64 Tf-B

Myospalax epsilanus

Transbaikalia, Chita territory 2N=64, Tf-C

Myospalax aspalax

Transbaikalia, Chita territory 2N=62, Tf-A

Myospalax armandii

Transbaikalia, Chita territory, 2n=62-66, Tf-C1 Myospalax smithii, China, 2n=62 NJ RAPD 463 fragments Phylogenetic trees of studied Zokor species

MST RAPD 463 fragments

RESULTS

Myospalax epsilanus

Transbaikalia

Myospalax psilurus

Primorye territory MST phylogenetic trees of studied Zokor species MST CR 518 bp

Interspecific relationships within the genus Myospalax (PAPD-PCR data)

M. aspalax – M. armandii

N 36

M. epsilanus – M. psilurus

45

H t

0.14

±0.034

0.20

±0.04

H s

0.1

±0.02

0.17

±0.02

D st

0.03

±0.01

0.03

±0.01

G st

0.25

0.16

Nm

1.48

2.62

D/S

0.08/0.92

N – number of specimens, genetic diversity

Dst

, calculated on the basis of the total within sample genetic diversity

Ht

and mean sample genetic diversity

Hs

, coefficients of genetic differentiation

Gst

, number of migrants per generation

Nm

, genetic distances

D

, and genetic similarity

S

, and performed exact test for population differentiation

Ex.(р) 0.00

0.08/0.92

0.00

Interspecific relationships within the genus Myospalax (CR- mt DNA)

M. smithii M. rufescens M. myospalax M. aspalax M. armandii M. epsilanus M. psilurus M. smithii

0 6 73 63 66 69 58

M. rufescens

0.0174

0

M. myospalax

0.2358

0.2339

77 60 65 69 58 0 57 38 60 51

M. aspalax

0.1723

0.1694

M. armandii

0.1873

0.1838

0.1767

0 23 35 27 0.1574

0.0673

0 32 29

M.

epsilanus

0.3276

0.1604

0.1785

0.1053

0.1012

0 31

M. psillurus

0.3098

0.1549

0.1567

0.0744

0.0819

0.0595

0 Estimate value of Kimura two-parametric distance matrix (above diagonal) and transitions and transversions (Ts+Tv) (below diagonal) for 7 taxa of

Myospalax

Dr. Marina V. Pavlenko Dr. Vladimir P. Korablev The study was partly supported by the RFBR (12-04-00795-a)

Thank you for your attention

The Zokor

Myospalax

is the endemic group of subterranean rodent in the East Asia.

More then 10 species are whole in this group, and only 4 of them there are in Russian Far East. Manchurian zokor

Myospalax psilurus

(Milne-Edwards, 1874) geographically distributed from Transbaikalia to Central China. In Russia there ate two peripheral populations. The first are distributed in east part of Transbaikalia, and second one occupies Khanka plain (south-west part of Primorsky Krai). The systematic ranks of these forms are not clear. In the literature,

M. epsilanus

(Thomas, 1912) is regarded as a subspecies or as a synonym of

M. psilurus

(Ognev, 1947, Gromov, Erbaeva, 1995; Zhang et al., 1997, Wilson, Reeder, 2005), or as a separate species (Lawrence, 1991; Pavlinov, Rossolimo, 1998; Pavlenko, Korablev, 1999). The complex of the genetic methods were used to study the differentiation in the

"M. psilurus - M. epsilanus"

group, and to clarify the systematic position of two peripheral population from the Russian Far East and Transbaikalia. The diploid number of chromosomes are 2n = 64 in all of studied zokors. There are also the significant differences in the structure of the karyotype between populations from the Transbaikalia region (9-12 M-SM, 10-13 ST, 8-A: "epsilanus") and the Russian Far East (9 M-SM, 13-14 ST, 8-9 A: "psilurus"). Furthermore, these two populations have two different variants of the electrophoretic blood protein (transferrin), each of them is a monomorphic for studied samples within the geographical region and marks the peripheral populations. Random Amplification of Polymorphic DNA PCR (RAPD PCR) obtained the specific markers and genetic evidence of differentiation between two peripheral populations. By sequencing of two mitochondrial DNA fragments (mt DNA), a 514 base-pair fragment of the control region and a 1141 base pair of the cytochrome b, we found the high lewel genetic differentiation between populations from Primorye and Transbaikalia. The all phylogenetic trees (NJ, MP, ML) are shown two groups of zokors from different geographical regions with high values of support. The genetic distances between these two groups are high, that comparable with those for the pair of closely related species

Myospalax aspalax

and

M. armandii

, which are regarded as a separate species taxa. Thus, the results confirm the hypothesis of the genetic differentiation of two populations

M. psilurus

from different geographical regions previously proposed on protein markers (Pavlenko, Korablev, 2003) and support a distinct taxonomic position the each of peripheral populations. Under the proposed hypothesis , populations of zokors from the territory of Primorsky Krai and Transbaikal region belong to different species

M. psilurus

(Milne-Edwards, 1874) and

M. epsilanus

(Thomas, 1912)

,

or semispecies within the superspecies

M. psilurus

.