[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Ceratopteris varieties (my 2 cents worth)

I have seen four distinct types of Ceratopteris in my wanderings.  The most
common one  and the olderst in the trade is the one called thalictroides in
the older books.  Its younger leaves have a lot of leaf area and are lobed,
rather than finely divided.  When the leaves get over 6 inches long they
begin to become more finely divided.  Occasionally another species or
variety shows up whose leaves always stay lobed like oak leaves, even when
quite large.  This, in the older books has been called cornuta.  There is
another variety whose leaves are more finely divided than thalictroides.
Even the very small leaves, less than an inch long are divided into narrow
branches.  This is called siliquosa in Rataj & Horeman.  More recently I
once saw in my local fish store a form that has even more finely divided
leaves, where the divisions are almost thread-like and look superficilly
like leaves of Cabomba, with "fans" of narrow divisions coming from common
points.  I kind of wish I had got my hands on that variety, but I didn't
have the time or the place to get it set up.

The naming of these types is hopelessly confused in the books.  What I knew
as cornuta, Rataj and Muhlberg call pteroides.  Kasselmann calls pteroides
a form with finely divided aerial leaves that have swollen petioles like in
water hyacinth leaves.   She says it does not grow well in tanks and is
rare in the aquarium trade.  What I knew as thalictroides, Muhlberg calls
cornuta.  Kasselmann doesn't show it.  What I knew as silliquosa, Muhlberg
and Kasselmann call thalictroides.  Kasselmann shows a form I have never
seen before as cornuta.  Its leaves are divided more than I ever saw for
the 'old' cornuta, but less than in the 'old' thalictroides.

To straighten this mess out, we need pictures of all these species or
varieties at different sizes from small plants to large.

Paul Krombholz, in warm, windy central Mississippi.