Natural classification: frogs (Rana nigromaculata) belong to Ranidae and lateral forest frogs, while bullfrogs belong to Ranidae and forest frogs.

Size: the body length of Lycopodium nigromaculatum is about 6-7cm, and that of Rana chensinensis is about 7- 17cm.

Appearance characteristics: Frog with black-spotted side folds has rough back skin, obvious back folds, long warts or moles on the side, light green or yellow-green back mixed with black stripes, bullfrog skin is smooth without back folds, and green back mixed with brown spots.

I. Natural classification

1, Frog (Frog) is a chordate, Amphibia, Anura, Ranidae, Frog.

2. Bullfrog belongs to Chordata, Amphibia, Anura, Ranidae and Ranidae.

Second, scale.

1. The body length of male and female frogs is about 6.2 cm and 7.4 cm respectively.

2. Bullfrog is one of the largest frogs in the world at present. The adult body length is about 7- 17cm, and the longest can reach more than 20cm.

Third, the distribution area

1. Rana nigromaculata is mainly distributed in China, Japan, South Korea, North Korea, Russia and other countries.

2. Bullfrog is native to North America, and is mainly distributed in China, Yunnan, Guangxi, Zhejiang, Fujian, Sichuan, Chongqing, Hunan and other provinces.

Fourth, the appearance characteristics

1. Frog with black-spotted lateral folds has rough back skin, obvious dorsal folds, multiple rows of longitudinal skin ridges with different lengths between folds, and long warts or moles on the side, while bullfrog has smooth skin without dorsal folds.

2. The back of Rana nigromaculata is light green or yellowish green, dark green and taupe, with black stripes. The back fold is golden yellow or light brown, and the abdomen is milky white, while the back of Rana nigromaculata is green with brown spots. The abdomen is white and the throat has yellow stripes.