Key to the 37 Chinese species of the genus Echiniscus

1. Cephalic appendages and cirri A present, other dorsal and lateral appendages absent............................... 2

- In addition to cephalic appendages and cirri A, other appendages present....................................... 12

2(1). Claws without spurs; cuticle sculpture: extremely fine and dense dots and large light patches; third median plate absent; cir- rus A c. ⅓ of body length; cuticle olive green........................................ E. viridissimus Péterfi, 1956

- Claws with spurs.................................................................................... 3

3(2). Cuticle sculpture comprises double granulation; eyes red; third median plate present; cirrus A less than ⅓ of the body length; cuticle red.................................................................. E. bigranulatus Richters, 1907

- Cuticle sculpture not as above.......................................................................... 4

4(3). Cuticle sculpture comprises large hexagons or circles, with a slightly raised rim enclosing a flattish, depressed surface.... 5

- Cuticle sculpture not as above.......................................................................... 6

5(4). Third median plate present; cirrus A more than ½ the body length; head and caudal plates facetted; sharp, elongate spur on legs I; cuticle red............................................................... E. reticulatus Murray, 1905

- Third median plate absent or indistinct; cirrus A less than ½ body length; caudal plate facetted; spur on legs I normal................................................................................. E. japonicus Morikawa, 1951

6(4). Cuticular sculpture comprises domed hexagonal granules.................................................... 7

- Cuticle sculpture not as above.......................................................................... 9

7(6). Cuticular sculpture comprises dark tubercles, very fine and dense dots and very fine light spots; third median plate absent; cirrus A slightly more than ½ of the body length; cuticle olive green.................... E. perviridis Ramazzotti, 1959

- Not as above........................................................................................ 8

8(7). Cuticle sculpture comprise domed hexagonal granules; third median plate absent; very strongly facetted head, shoulder and caudal plates; extreme pseudo-division of shoulder and caudal plates; lateral sub-plates; cirrus A c. ⅓ the body length; cuti- cle red........................................................................ E. tessellatus Murray, 1910

- Cuticle sculpture comprise domed hexagonal granules; third median plate absent; caudal plate unfacetted; cuticular fold or papillae in region of the eye; eyes absent; cirrus A c. ⅓ the body length; cuticle red............. E. tardus Mihelčič, 1951

9(6). Cuticular sculpture comprises connected granules forming a lattice network.................................... 10

- Cuticular sculpture not forming a lattice network.......................................................... 11

10(9). Cuticular sculpture comprises connected granules forming a lattice network; third median plate absent; caudal plate facetted; cirrus A c. ¼ of the body length; cuticle yellow-orange.............................. E. pseudelegans Séméria, 1994

- Cuticular sculpture comprises small dense granules connected by fine strips; third median plate absent; caudal plate unfacet- ted; cirrus A more than ½ the body length; cuticle red.................................... E. wendti Richters, 1903

11(9). Cuticular sculpture comprises regular punctuations; third median plate absent; head, shoulder and caudal plates facetted; eyes red; cirrus A very short <10% body length................................ E. limai da Cunha and Ribeiro, 1964

- Cuticular sculpture comprises large dark granules; third median plate absent but area sculptured; caudal plate unfacetted; cir- rus A very short <15% body length; cuticle dark green.................................... E. viridis Murray, 1910

12(1). Claws without spurs................................................................................. 13

- Claws with spurs (at least on leg IV).................................................................... 18

13(12). Median plate 3 present............................................................................... 14

- Median plate 3 absent............................................................................... 16

14(13). Lateral appendages at A, B, C, D and E present........................................................... 15

- Lateral appendages A 10%> body length, C and E short spurs; dorsal appendages C d short spur, D d 10% body length; cuticu- lar sculpture comprises fine dots, some coarse and irregular; eyes red................................................................................................. E. angolensis da Cunha and do Nascimento Ribeiro, 1964

15(14). Cuticular sculpture comprises double granulation, close polygons & irregular pores; lateral cirri A, B, C, D and E present, all less than ⅓ body length; dorsal appendages at C d and D d short (10% body length); colour light yellow....................................................................................... E. cheonyoungi Moon and Kim, 1994

- Cuticular sculpture comprises round, regular and close dots; lateral plates present; lateral cirri A, B, C, D and E present, all c. ⅓ body length; dorsal appendages at C d and D d short (10%> body length)............. E. quadrispinosus Richters, 1902

16(13). Eyes black; cuticular sculpture comprises double close polygons & irregular pores; lateral appendages A ¼ body length, C and D 15% body length, E <⅓ body length; dorsal appendages C d and D d <10% body length; colour red........................................................................................ E. taibaiensis Wang and Li, 2005

- Eyes red or absent.................................................................................. 17

17(16). Cuticular sculpture comprises round, regular, close spaced dots; lateral cirri A <⅓ body length, B <⅓ body length, C 40% body length, and E 70% body length, dorsal appendage D d c. 10% body length; eyes red; colour red...................