Table 2. Mean percentage base composition and GC content of the first, second, and third codon positions from 187 COI sequences of 41 fishes collected from Rongcheng Bay.

	Mean	Minimum	Maximum	Standard error
A%	23.5	20.6	26.8	0.1098
T%	29.2	25.7	34.3	0.1475
C%	28.5	24.3	34.4	0.1475
G%	18.7	16.2	21.0	0.0694
GC%	47.3	41.4	53.4	0.1912
GC% codon 1st position	56.6	54.1	58.9	0.3626
GC% codon 2nd position	43.0	41.5	44.7	0.0401
GC% codon 3rd position	42.2	24.8	60.3	0.5717