Apuleia zeyheri Less., 1832

Karis, Per Ola & Mckenzie, Robert J., 2024, Second-step lectotypification of Stobaea rigida and reassessment of heterotypic synonyms of Berkheya rigida (Asteraceae, Arctotideae), Phytotaxa 641 (4), pp. 267-276 : 272

Apuleia zeyheri Less.

As mentioned in the preceding section, Lessing (1832) described S. rigida as having shortly radiate capitula. For a different species with discoid capitula, Lessing (1832: 64) published the new name Apuleia zeyheri . Lessing (1832) based this name on a single specimen, at the time in the personal herbarium of C.F. Ecklon, from a gathering by C.L.P. Zeyher from Hottentots Holland. Roessler (1959) acknowledged not seeing the original material, but placed A. zeyheri in the synonymy of B. rigida on the basis of Lessing’s description of the new species. Roessler (1959) interpreted that A. zeyheri differed from typical B. rigida in having longer involucral bracts and more deeply incised leaves, but that it otherwise fell within the range of morphological variation of B. rigida .

We consider that Lessing’s description of A. zeyheri cannot be unambiguously associated solely with B. rigida . The character states mentioned by Lessing (1832) are compatible with multiple Berkheya species. The upper cauline leaves of A. zeyheri were described by Lessing (1832) as glabrous and concolorous, features that are characteristic of numerous Berkheya species other than B. rigida . Lessing’s description of the involucral bracts as “ margine recurvatis, inflato-concavis, oblongo-ellipticis ” could apply to multiple species in series Rigidae .

The location of the original material for A. zeyheri , if still extant, is uncertain. No material collected by Zeyher from the Hottentots Holland area and annotated by Lessing with the name Apuleia zeyheri has been examined to date. Harvey (1865: 500) stated, under Stobaea atractyloides , “ S. Zeyheri, Less. ! of which I have seen the original, but now half-rotten specimen (in Hb. Sd.) [the private herbarium of Otto W. Sonder in Hamburg] marked by Lessing himself, does not seem to me to have any stable characters; those he enumerates as separating it from S. atractyloides are certainly variable.” Sonder accumulated the largest collection of Ecklon and Zeyher specimens, of which most are now housed in Herb. S, but duplicate specimens can be found in many herbaria ( Nordenstam 1980). Four sheets of specimens collected by Zeyher from Hottentots Holland are housed in Herb. S (S08-16453, S08-16454, S08-20416, and S08-20407). None are presently identified as B. rigida . Owing to the ongoing renovation of the Swedish Museum of Natural History buildings housing the collection, the specimens in Herb. S are currently inaccessible for examination to clarify their identity.

A search for Berkheya specimens collected by Zeyher from Hottentots Holland housed in other herbaria is ongoing. In Herb. SAM is a specimen, likely collected by Zeyher but with a label in C.W.L. Pappe’s handwriting bearing the locality information “In planit. ad Hott.- Holland. Nov.” but with no identification or collector details. It cannot be assumed to be part of the same gathering that formed the original material for A. zeyheri , but the leaf and involucral bract morphology is unquestionably consistent with B. rigida .

Based solely on Lessing’s description of A. zeyheri , we cannot confidently concur with Roessler (1959) that A. zeyheri is conspecific with B. rigida . We provisionally retain the name Apuleia zeyheri as a heterotypic synonym of B. rigida , but point out that examination of original material or a duplicate specimen from the same gathering is required to confirm this interpretation.