Pictures and line drawings

magnum4 · Post by **magnum4** » 12 Nov 2003, 23:39

Ichthyologists don't like going on fin patterns too much as they have a nasty habit of being bitten off, badly preserved and generally unreliable or even unavailable. Give you another example, Corydoras caudimaculatus - the spot is on the body, not the fin.

Thanks jools. To add another point i've never liked the way that holotypes are preserved(I know it can be useful to have a record)IMO most of the time pictures and drawings are more useful for identification.

Post by **Silurus** » 12 Nov 2003, 23:47

I.M.O. most of the time pictures and drawings are more useful for identification.

Holotypes are the only way to objectify the name. If you look at the quality of some of the drawings in original descriptions (they look like they were made by a three-year old and in some cases, I have trouble even telling what genus they are).

magnum4 · Post by **magnum4** » 12 Nov 2003, 23:53

Bad example should have left out drawings and just gone with pictures are these good enough to objectify the name, using modern technology?

Post by **Silurus** » 12 Nov 2003, 23:57

are these good enough to objectify the name, using modern technology?

Still not a good idea. You are trying to represent a three-dimensional object in two dimensions. A lot of info gets lost that way.

MC · Post by MC » 13 Nov 2003, 15:41

Have the methods for preserving holotypes changed over the years? or is it still case of preserving in resin?

Are any of the new technologies used to record data? MRI for example? Or are things still done the old fashion way?

Post by **Silurus** » 13 Nov 2003, 16:14

Scientific material has been preserved prety much the same way for a century or more using formalin and in ethanol for long-term storage. This is not the ideal method of preservation, since there will inevitably be shrinkage over the years.

In recent years, computed tomography has been used to study the internal anatomy of rare types.