Arlea, WOMERSLEY, 1939

Bernard, Ernest C., 2017, Arlea judithnajtae n. sp. (Collembola: Isotomidae), a temperate North American member of a Gondwanan genus, Zoosystema 39 (1), pp. 87-93 : 92

KEY TO THE SPECIES OF ARLEA WOMERSLEY, 1939

1. Two pairs of ocelli present ........................................................................................................................... 2

— Ocelli absent ............................................................................................................................................... 3

2. Mucro falcate; all setae smooth .................................................................................. A. lucifuga ( Arlé, 1939)

— Mucro falciform with additional small ventral tooth; macrosetae strongly barbed ........................................... .............................................................................................................. A. spinisetis Mendonça & Arlé, 1987

3. Anterior face of manubrium with 1 + 1 setae ................................................................................................ 4

— Anterior face of manubrium with 4 + 4 or 5 + 5 setae ................................................................................... 7

4. Dens with at least 20 posterior setae .............................................. A. arenicola Abrantes & Mendonça, 2005

— Dens with 17 or fewer posterior setae .......................................................................................................... 5

5. Dens with 10 posterior setae; all Abd. V sensilla conspicuous, plump ............................................................. ...................................................................................... A. adetolai Mendonça, Abrantes & Fernandes, 2006

— Dens with at least 15 posterior setae; Abd. V sensilla slender ....................................................................... 6

6. Dorsal sensilla of Abd. I-III in middle setal row; Ant. IV with seven prominent sensilla; posterior face of manubrium with 26 setae ....................................................................................................... A. judithnajtae n. sp.

— Dorsal sensilla of Abd. I-III in posterior setal row; Ant. IV with 8-9 prominent sensilla; posterior face of manubrium with 18 setae ............................................... A. psammophila Mendonça, Abrantes & Fernandes, 2006

7. Anterior face of manubrium with 4 + 4 setae; Ant. IV with five prominent sensilla ....... A. tridens Barra, 1997

— Anterior face of manubrium with 5 + 5 setae; Ant. IV with seven prominent sensilla ...................................... .................................................................................................................. A. caeca Rapoport & Rubio, 1968