3.1 Genetic diversity
A total of 300 COI and Cyt b gene datasets (2598 bp) were
obtained of L. spadiceus from eight geographic locations (Figure
1). 94 polymorphic sites were detected among all individuals, including
28 parsimony information sites and 66 singleton variable sites (Table
1). The average nucleotide composition was 23.2% adenine (A), 27.3%
thymine (T), 31.6% cytosine (C), and 17.9% guanine (G), with a
slightly higher content of A+T (50.5%) than G+C (49.5%), showing a
clear anti-G bias. The mutation
of DNA was unsaturated for the transition/transversion (Ts/Tv) of bases
in the COI and Cyt b gene datasets, which was 3.73. 95
haplotypes were identified (GenBank accession numbers: OQ970201-OQ970253
and OR428269-OR428309), the majority of which were unique haplotypes
(89.47%). Only ten haplotypes were shared between populations (Hap_1,
Hap_2, Hap_4, Hap_5, Hap_17, Hap_22, Hap_23, Hap_25, Hap_30, and
Hap_65), and the most common Hap_1 (24.0%), Hap_2 (19.3%), and
Hap_22 (11.0%) were found at each population (Figure 2).
Total haplotype diversity
(H d) was high (H d =
0.874±0.013), while nucleotide diversity (π ) was low
(π =0.00075±0.00058) (Table 1), showing the high haplotype
diversity and low nucleotide diversity.
The correlation between genetic
diversity and longitude and latitude of sampling locations showed that
the haplotype diversity (r = 0.29) and nucleotide diversity
(r = 0.31) of L. spadiceus populations tend to rise with
latitude but did not change significantly with longitude (r =
0.08 and 0.04, respectively) (Figure 3).