typification of algae

[Olivier De Clerck]

Dear taxonomists,

Since a while I've been confronted with typification of algae. As most algal
taxonomists never indicated a holotype, there wasn't a
problem in many cases. However, now I'm trying to designate a type to
Dictyota dumosa Boergesen. The original description (Kgl. Danske
Vidensk. Selskab. Biol. Med. 12: 37-38, pl. 6) provides us with a
single collector number (5103, type), several localities near Bombay and a picture
of 2 specimens (Back Bay, Bombay = 5103) which are also present in the type collection.

Sorry if I'm confused concerning the different option but I'll sum the different possibilities
concerning the typification for you.

1). The two specimens on the picture are to be considered as
holotype. The rest of the collection remains isotype.

2). All the specimens from Back Bay are holotype. The other
localities in the protologue are isotype.

3). Choose a single specimen from Back Bay, preferably one which was
illustrated. The other specimens from Back Bay become lectotype. The
rest of the collection remain isotype.

Hope some of you can provide me with some useful advice concerning
the correct status of this type collection. I think a lot of the
problems can be solved by clarifying whether a type is a specimen or
a collection.

Looking forward hearing from you,

Olivier De Clerck


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Olivier De Clerck
Dept. Morph., Syst. & Ecol., Lab. Botany
K.L.Ledeganckstraat 35 - B-9000 Gent, Belgium
tel 9-264.50.64 / fax 9-264.53.34 / olivier.declerck at rug.ac.be

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