Milnesium Doyère, 1840

Rocha, Alejandra M., González-Reyes, Andrea X., Ostertag, Belén & Lisi, Oscar, 2022, The genus Milnesium (Eutardigrada, Apochela, Milnesiidae) in Argentina: description of three new species and key to the species of South America, European Journal of Taxonomy 822 (1), pp. 1-54 : 47-48

Dichotomous key of the species of Milnesium Doyère, 1840 from South America

1. Dorsal cuticle smooth ....................................................................................................................... 2

– Dorsal cuticle ornamented (pseudopores-reticulum-dimples) .......................................................... 5

2. Claw configuration [2-2]-[2-2] .......................................................... M. kogui Londoño et al., 2015

– Claw configuration [3-3]-[3-3] ......................................................................................................... 3

3. BT funnel-shaped in adults (posterior/anterior width ratio lower than 65%) ..................................... .............................................. M. eurystomum Maucci, 1991 (amended by Michalczyk et al. 2012b; amended by Morek et al. 2020a)

– BT about cylindrical in adults (posterior/anterior width ratio higher than 75%) ............................. 4

4. Pt of BT standard width lower than 52 in adults .................. M. brachyungue Binda & Pilato, 1990

– Pt of BT standard width higher than 52 in adults .............................................. M. quiranae sp. nov.

5. Claw configuration [3-3]-[3-3] ......................................................................................................... 6

– Claw configuration different ............................................................................................................. 7

6. Nine rows of pseudoplates, pt of SS [63.8–66.7]; pt of BT standard width [58.1–65.6] ................... ..................................................................................................... M. beatae Roszkowska et al., 2015

– Without pseudoplates, pt of SS [70.0–73.7], pt of BT standard width [24.2–32.3] ........................... ............................................................................................ M. argentinum Roszkowska et al., 2015

7. Claw configuration [2-2]-[2-2] .............................................. M. katarzynae Kaczmarek et al., 2004

– Claw configuration different ............................................................................................................. 8

8. Claw configuration [2-3]-[2-2], pt of BT standard width [46.1–56.9], with 9 rows of pseudoplates ... ................................................................................................................................... M. irenae sp. nov.

– Claw configuration [2-3]-[3-2] .............................................................................................................9

9. Cuticular dimples arranged in 10 bands, small tubercles around all claw bases, pt of BT standard width [55.2–64.0], young specimens with claw configuration [2-2]-[2-2] .... M. pelufforum sp. nov.

– Cuticular dimples present not forming bands, pt of BT standard width [33.0–38.0], no tubercles around claw bases ..................................................... M. krzysztofi Kaczmarek & Michalczyk, 2007

Abbreviations: BT = buccal tube; SS = stylet support insertion point on the buccal tube.