Eulimnadia michaeli Nayar and Nair, 1968

Sanoamuang, La-orsri, Padhye, Sameer M. & Rogers, D. Christopher, 2020, Review of the (Branchiopoda: Spinicaudata: Limnadiidae) of Tropical Asia, with the Description of a New Species., Zoological Studies 59 (41), pp. 1-7 : 5-6

Eulimnadia michaeli Nayar and Nair, 1968

= Limnadia michaeli ( Nayar and Nair, 1968)

= Eulimnadia khoratensis Rogers, Dadseepai, and Sanoamuang, 2016

New Status

Comments: This species was treated as a species inquirenda by Rogers and Padhye (2015), based on the lack of type material and poor descriptions. In 2016, Rogers et al. (2016b) described what was believed to be a new species from the Khorat Plateau in north central Thailand. Padhye and Kulkarni (2017) reported E. khoratensis from India and examined the extensive morphological variation in this species. All these authors were unaware of the paper by Samyiah et al. (1985), wherein scanning electron micrograph images of topotype material of E. michaeli , including the egg, were presented. There is little doubt that, based on the images of the eggs, E. khoratensis is a junior synonym of E. michaeli . Rogers et al. (2016: 570) wrote: “… it is possible that E. khoratensis n. sp. could be a junior synonym of E. gunturensis Radhakrishna and Durga Prasad, 1976 , Eulimnadia michaeli Nayar and Nair, 1968 , or Eulimnadia ovata Nayar, 1965 if the morphologies of the eggs of these species are ever properly described according to modern standards.”

This species ranges across tropical Asia from India, Sri Lanka, and Thailand ( Rogers and Padhye 2015; Rogers et al. 2016a; Padhye and Kulkarni 2017). The types of E. michaeli are presumed lost, but the types of E. khoratensis are deposited at the Muséum national d’Histoire naturelle, Paris (MNHN-IU-2014-17472).

Keys to the Tropical Asian Eulimnadia (key adapted from Padhye et al. 2018)

1 Egg cylindrical ........................................................................... 2

- Egg spherical/ sub-spherical ....................................................... 3

2(1) Flat ends dilated into flanges ........................... Eulimnadia bondi

- Domed ends without flanges ...................................... Eulimnadia braueriana / Eulimnadia indocylindrova (Note: possible synonyms)

3(1) Polygons separated by thin, narrow ridges ................................. 4

- Polygons separated by thick, rounded ridges; polygons with a narrow slit in the central depression; egg with 18–26 polygons ... ...................................................................... Eulimnadia michaeli

4(3) Polygons with floors bearing obvious central pores or grooves .... ..................................................................................................... 5

- Polygon depression floors smooth, unornamented; egg with 20–26 polygons ..................................... Eulimnadia magdalensis

5(4) Egg with 12–16 polygons; depressions ornamented randomly with small groove/s and 1–3 pores on either side of the groove ... ....................................................................... Eulimnadia chaperi

- Egg with 14–18 polygons; depressions ornamented with a narrow central groove .................................. Eulimnadia cryptus sp. nov.