>>Having focussed on _Drosera_, I have completely overlooked/forgotten some
>>really interesting fossils of (NB: the *very* delicate) _Aldrovanda_ from
>>Europe and boreal Asia from as early strata as the Eocene and Oligocene
>
>Jan, I am most interested. I thought the only CP fossils known were of
>pollen or something like that. Do go on!
OK, here we go.
I have now traced some literature. The most recent review is in:
T.V.JAKUBOVSKAJA, "Rod _Aldrovanda_ (Droseraceae) w pleistocenye Belorussii",
Bot.zhurn. (Lenin- i.e. Petrograd) 76(1):109-118, t.1&2 (1991).
The only (minor) disadvantage of which being the fact that it is written in
Russian. Many new species are described from Pleistocene strata of
Belorussia, on p. 116 a table is presented with all fossil species of
_Aldrovanda_ (NB: all specimens cited are *seeds*, no pollen nor plants)
described so far. It reads like:
-----------------------------------|----------------------------------------
: |
Holocene : |
-----------------------------------|----------------------------------------
: : |
: late : |
:-----------_A.vesiculosa_ L.---------------------------------
: : | |
Pleistocene : middle : _A._ sp.2 |
:--------------------|-----|----------------------------------
: :_A.rugosa_ | _A.borysthenica_ Wieliczk.,
: early :J.V.Jakub.\| _A.dokturovskyi_ Dorof. _ A._sp.1
-----------------------------------Y-----|-_A.zussii_-----------------|-----
: : | |/T.V.Jakub.
: late :_A._sp.(Dworec) Y |
:--------------------|-----|---------------------------- -----
: : A | | |
Pliocene : middle : l | |
:------------------d-|-----|----------------------------|-----
: : r | | |
: early : o | _A.europaea_ Negru |
---------------------------------v-|-/--------------------------------|-----
: : a |/ |
: late : n Y |
:------------------d-|----------------------------------|-----
Miocene : : a | / |
: middle :_A.eleanorae_ P.Nikit. _A.nana_ Dorof.
:--------------------|----------------/-----------------|-----
: : | C |
: early :_A.praevesiculosa_ / l |
--------------------------Kirchh.--|------------- ------------------a-|-----
: | / v |
: | / a |
: | / t |
Oligocene : | / a |
: | / e |
: _A._sp. / _A.clavata_
: (Stradubka) / \ Dorof. |
: | / _A.sobolevii_
-----------------------------------|--_A.sibirica_----------\--Dorof.-|-----
: | V.Nikit. O /
: | / b \ /
: | / l \ /
: |/ i \ /
: Y q Y
Eocene : | u _A.ovata_
: _A.intermedia_ a (M.Chandl.)
: E.Reid & M.Chandl. e M.Chandl.
: | |
: | |
-----------------------------------|-----------------------------|----------
The Eocene fossils are from S England, most of those from Oligocene strata
are from Siberia or E Europe (_A.praevesiculosa_ is from E Germany, but
similar fossils have been found in Spain, too). The late Tertiary and
Pleistocene fossils are very close to the modern _A.vesiculosa_, and they
would probably not be recognized as specifically distinct from it if they
were recent forms. Most of these are from Belorussia.
Note that there was a (now extinct) separate lineage in the genus (viz.
sects. Obliquae/Caudatae) extant already in the Eocene. This could indicate
a rather old age even of this genus. If we assume (I do assume so) that
_Aldrovanda_ is one of the more *modern* genera in Droseraceae, the
supposedly "old" _Drosophyllum_ (already existing in the Paleocene or even
late Cretaceous?) might have lived among rather primitive angiosperms...
Kind regards
Jan