Re: _Pinguicula_ from arctic Spain

Jan Schlauer (Jan@pbc-ths1.pci.chemie.uni-tuebingen.de)
Fri, 10 May 1996 09:50:22 +0100

Dear Juerg,

RE Arctic:

>(...) Nevertheless the southernmost sites are on Vancouver
>island around 50 degrees N latitude which is far more N than New Hampshire
>but not far more N than our Alps. May be the Vancouver plants are more
>tolerant towards shorter day length than the Scandinavian ones
>(southernmost sites at 60 degr. N).

The southernmost known site of _P.villosa_ is in Korea, more S than
Vancouver or the Eu Alps. The climate at the E coasts of the large
continents is rather different from that at the W coasts, and arctic
elements from several families can be seen to "descend" southwards at the E
end.

>P. alpina originated in the Himalayas from where it spread to N (Siberia)
>and then to W and SW (Scandinavia, Scotland, Jura, Tatra, Alps, Pyrenees)
>and therefore does not exist in the Causasus and its neighbouring mountain
>ranges.

An opposite theory can be postulated with a Eu origin of _P.alpina_. The
present range is the product of glacial migration and postglacial
fragmentation showing numerous relict occurrences (leading to the arctic +
alpine pattern). Therefore, it is rather difficult to tell where this
species has really originated or how it has migrated (apart from the notion
that it must have been a N route because the Caucasus was not reached). If
_P.alpina_ has originated in the Himalayas, how did its ancestors (which
ancestors?) then come there from C Am?

> It is not an originally northern species and therefore not
>sensitive to the day length as possibly P. villosa.

No species of _Pinguicula_ is originally a northern (i.e. arctic) one
as 1. The whole genus has rather certainly originated in the tropics of
C Am. 2. _P.villosa_ (the only circumarctic element in the genus) is
probably not the descendant of any recent temperate species (it has
2n=16 chromosomes, the only geographically possible candidate would be
_P.vulgaris_ with 2n=8x=64).

So even _P.villosa_ must be the product of (supposedly Pleistocene or
perhaps earlier) migration and extinction, with an origin further S.

RE Spain:

>3) To give the specimens from the Tortosa region the rank of a distinct
>species has some good reasons,

I do not see these reasons if _P.longifolia_ is considered sensu lato
(incl. "P.fiorii"), cf. especially _P.l.caussensis_ (2n=??).

> but then it must be named P. dertosensis and not P. submediterranea.

Not really. At specific rank submediterranea is the oldest epithet and has
thus priority. Only at varietal or subspecific rank, dertosensis is to be
applied. It is the fault of our Spanish colleagues (but not illegitimate!)
that they have not adopted and recombined the epithet of Canigueral even if
they cite his name (they do of course not cite my combination or any other
synonym, or any specimen examined by Casper etc. etc. 8-( ). To add to the
confusion, they have chosen a plant from the Sierra de Cazorla (i.e.
geographically closer to _P.mundi_ and _P.vallisneriifolia_ than to
_P.l.dertosensis_) as the type of "P.submediterranea".

Kind regards
Jan