Dimeria scrobiculata C.B.Clarke ex Koord. (1911)

Veldkamp, J. F., 2016, A revision of Dimeria (Gramineae-Dimeriinae) in Malesia with a note on Cymbachne, Blumea 61 (3), pp. 207-214 : 210-213

Dimeria scrobiculata C.B.Clarke ex Koord. (1911) 102. — Lectotype: Ottolander 358 (BO), designated here.

= Arthraxon hispidus (Thunb.) Makino var. hispidus .

Cymbachne

Cymbachne Retz. (1791) was described with as the single species C. ciliata represented by a single (!) specimen collected by König in Bengal. Retzius material may be expected to be in Lund (LD), but it has been long lost. It was not found by Fischer (1932), but as noted by Bor (1960: 139) a specimen is present in the Zetterstedt herbarium (LD 1228279). It was annotated not by Retzius, but by Zetterstedt (Messrs. P. Frodén and P. Lassen, LD, in litt.). Bor identified it as D. alata Hook.f. , a Sri Lanka endemic ( Fig. 1 , 2 ).

However, this cannot be original material. From the reference to Sprengel (1824) on the label and the absence of any men- tion of König it would seem that after 1824 Zetterstedt tried to identify a collection, and besides the incongruence with the original description, this cannot be the type of C. ciliata . That it came from Bengal, as is noted on the label, might well have been a deduction from the provenance cited by Retzius and subsequent authors.

Bor wrote “the description might easily apply to a species of Dimeria … no need for a change of name”. However, the description mentions the presence of paired spikelets, whereby it can never refer to Dimeria R.Br. (1810) , which is one of the few andropogonoid genera characterised by solitary ones. Dimeria spikelets have only 2 stamens, 3 are described here, and depicted by Presl (1830; but described as two!). This is most fortunate, as Cymbachne has priority over Dimeria , and there is now no need for a proposal for conservation to prevent about 70 new combinations.

Probably following Bor, Clayton & Renvoize (1986: 376) have suggested that it was based on a damaged specimen of Dimeria R.Br. and thus it is perpetuated in the literature.

Willdenow (1797) unseen and without argumentation trans- ferred it to Rottboellia L.f. as R. cymbachne , a superfluous name, as at the time there was no R. ciliata . There is no duplicate in the Willdenow herbarium (B). This combination, without any further reference, was used by Steudel (1854: 362).

Hackel (1889: 450) stated to have seen a specimen collected by König in Copenhagen (C), labelled as Cymbachne ciliata . He observed (my translation) that “the description is quite obscure and by no means without errors, for what he calls the female flowers seem to be nothing else than thick pedicels, remaining after de male spikelets have fallen off. Besides what else Retzius adds, agree well with the Koenig specimen and I do not doubt that I have described the same as Retzius’ plant.A specimen in the herbarium Retzius, now in Lund, is to be wished for”. In C there are two (!) sheets, which makes them suspect, be- cause a single sheet was expected in Lund:

– C10016736 with ‘ Rottboellia cymbachne Willd. ?’ and a label by Hackel: Andropogon cymbachne Hack. , and on the back annotated as part of the Herbarium Vahl, and with the names Andropogon cymbachne and Cymbachne ciliata Retzii (K neg. 19385) and ‘Konig’ ( Fig. 3 ).

– C10016737 with a label by Hackel ‘ Andropogon cymbachne Hack. / Cymbachne ciliaris Retz. ’ and a reference to Hof- man Dory (??) (K neg. 19384). The ‘ Rottboellia ’ in pencil is to be neglected. A note by Clayton states “does not match description” ( Fig. 4 ).

These specimens belong to Andropogon canaliculatus Schumach. This is an African species ranging from Mali to Tanzania and Zimbabwe and never could have been collected by König. Obviously, they were mislabelled and very well could be iso- types of Schumacher’s species described from Ghana, the type of which has otherwise not been found as yet. However, the type of A. eucnemis Trin. (1832) may very well be an isotype of this, and is here designated as the neotype.

Note that later typifications do not make a name superfluous (ICN Art. 52, Note 2).

Hackel for some reason with a query included Arthrostachys Desv. (1831) with A. gracilis . This was described without provenance or collector and is immediately distinct by the articulate inflorescence axes. It was not mentioned by Steudel (1854). Clayton & Renvoize (1986: 349) and Soreng & Pennington (2003) regarded it as a synonym of Andropogon with which I can agree. Arthrostachya Link (1827) is not an earlier homonym (Art. 53.3.Ex.12).

The undaunted Roberty (1960) not having seen the type, either, nevertheless accepted Cymbachne for 8 Asian and African species with 9 varieties and 72 subvarieties, which others have regarded as taxa belonging to Andropogon (incl. Arthrostachys Desv. , Diectomis Kunth , Homoeatherum Nees , and Pollinia Spreng. , p.p., Rottboellia auct.).

It may be noted that Palisot de Beauvois (1812: 109, 159) mentioned a “ Cymbachne Lour. ”. This is an error for Stegosia Lour. From the diagnosis and description I have the impression that he had an unawned species of Ischaemum ( I. muticum L.?) before him.

Figures

Fig. 1 The Zetterstedt sheet in Lund (1228279).

Fig. 2 The Zetterstedt label in Lund (1228279).

Fig. 3 Backside of C 10016736.

Fig. 4 Sheet C 10016737.