10. Echiniscus arctomys Ehrenberg, 1853 sensu lato [T]

Terra typica: Switzerland (Europe)

Argentina:

• 41°59′S, 71°34′W; 300 m asl: Rio Negro Province, El Bolsón, Valley of Rio Azul, mosses on tree ( Myrceugenia exupca) in the Myrceugenia exupca - Nothofagus dombeyi marsh forest. Iharos (1963)

• 41°59′S, 71°31′W; 360 m asl: Rio Negro Province, El Bolsón, foot of Piltriquitron Mt., mosses on wet cliff of promontory, partly on soil and mosses on dry ledge (2 samples). Iharos (1963)

• 41°59′S, 71°31′W; 460 m asl: Negro Province, El Bolsón, foot of Piltriquitron Mt., live and decayed mosses on and under stones on cliff. Iharos (1963)

Brazil:

• 22°58′S, 43°15′W; 450 m asl: Rio de Janeiro State, neighbourhood of Rio de Janeiro, Tijuca National Park, mosses and algae. Rahm (1931, 1932)

Record numbers: Argentina: 3, Brazil: 1; total: 4.

Remarks: Currently E. arctomys is considered a species complex nested within a larger group ( arctomys group - sensu Ramazzotti & Maucci 1983), defined via a single pair of body cirri but with variable cuticle sculpture and other morphological traits. The loss of body cirri is a potential homoplasy while diverse cuticular sculpture and other traits require a number of evolutionary steps, so it is very likely that the arctomys group (sensu Ramazzotti & Maucci 1983) is polyphyletic, but this has to be verified via integrated morphological and molecular techniques.

The nominal species of the complex was originally described from Europe (Ehrenberg 1853), so this South American record requires confirmation.