Estonia
Endemic
vascular
plants include the Saaremaa Yellow Rattle Rhinanthus osiliensis
(Univ.
Tartu WM) (et.wikipedia)
which is sometimes considered a subspecies of Rhinanthus rumelicus. A marsh
orchid Dactylorhiza
osiliensis (Enno-Kustav
Väljal)
from Saaremaa is someimes considered distinct from Dactylorhiza praetermissa.
Endemic hawkweed
microspecies include Hieracium aphanum (eElurikkus), Hieracium nesaeum (eElurikkus),
Hieracium niveolimbatum (GBIF),
and Hieracium
harjuënse (Internet Archive). Other endemic plants include the Saaremaa Hawthorn Crataegus
osiliensis (eElurikkus),
the Viidumäe Hawthorn Crataegus
viidumaegica (eElurikkus),
the dandelions Taraxacum
stellare (JSTOR)
and Taraxacum lehbertii
(eElurikkus),
and perhaps a valerian Valeriana
estonica (eElurikkus).
Endemic invertebrates include a black fungus gnat Cratyna palustricola (GBIF), the horsehair worms Gordius
balticus and Gordius terminosetosus (both at kirj.ee pdf),
and a nematode Rhodolaimus
estonicus (Brill).
Fungi known only from Estonia include Cladobotryum gracile and Cladobotryum compactum (both on p. 10 of ResearchGate pdf) and Suillosporium caricis (ResearchGate).
Estonian endemic plants are indicated on the checklist at (Saxifraga WM).