
Fig 10 - Limnesia Undulatoides ?
Why Limnesia undulatoides.
While trying to find whether this water mite could be a Limnesia undulata (see my notes below) I found the picture presented by Kinga DZIERZGOWSKA and Andrzej ZAWA L (in Hydrodroma pilosa BESSELING, 1940 AND Limnesia undulatoides DAVIDS, 1997 (ACARI, HYDRACHNIDIA) – NEW RECORDS FROM POLAND) is very close to that I can see on my pictures.
In the paper of Van Haaren and Tempelman the Limnesia Undulatoides is described as
large, brightly coloured species with red legs and pedipalps. Acetabulae remarkably small
As shown on my pictures the legs of the water mite shown on this article are not red at all but as Harry Smit think that it’s undulatoides.
The abandoned idea of Limnesia undulata.
Elements used for the identification. In favour of Limnesia undulata.
- 4 eyes
- Small peg under the first segment of palpi
- Shape of the genital area
- Shape of the coxae plates
- Shape of the junction of the 2 first coxae plates
Elements that doesn’t match with Limnesia undulata.
Following the elements given in the paper of Ton van Haaren & David Tempelman.
- The epimera of Undulata are yellowish on the Undulata, rather blue on this one.
- The colour is more bright reddish than yellowish.
- The general size and shape looks like Limnesia fulgida (as said in the description of Limnesia undulatoides).
- The position of the acetabular plates in the genital field.
References
- The dutch species of limnesia, with ecological and biological notes (acari: hydrachnidia: limnesiidae) Ton van Haaren & David Tempelman – Nederlandse Faunistische Mededelingen 30 ‒ 53:74
- Hydrodroma pilosa BESSELING, 1940 AND Limnesia undulatoides DAVIDS, 1997 (ACARI, HYDRACHNIDIA) – NEW RECORDS FROM POLAND Kinga D Z I E R Z G O W S K A and Andrzej Z A W A L (link)
- Microcosmos.nl : the page of Gerard Visser on Limnesia Undulatoides.
- Agroeconet : Limnesia Undulata; In russian but some clear pictures of the epimera and the genital area.
Thanks.
I greatly thank David Tempelman who replied kindly to my questions on this Limnesia and who provided me a copy of his paper. I also thanks Harry Smit who has confirmed this identification.
Other pictures.

Genital area acetabula coxae

Limnesian peg

Lateral view with palpi

Other lateral view

Frontal view with the 4 eyes

Other general view

Estimation of the length
This is Limnesia undulatoides.
Best wishes,
Harry