Chenopodium acerifolium

Mosyakin, Sergei L., 2017, Notes on taxonomy and nomenclature of Chenopodium acerifolium and C. betaceum (C. strictum auct.) (Chenopodiaceae), Phytotaxa 324 (2), pp. 139-154 : 141-142

Chenopodium acerifolium : problems with earlier lectotypifications, and designation of the epitype

Chenopodium acerifolium was recently lectotypified by Sukhorukov (2014: 227) based on a specimen from LE: “ Lectotypus (Sukhorukov, designated here): [ Украина] In ins. Borystheni Kioviae, ex herb. Besser (LE!)”. This specimen is a single plant with a few cauline leaves and without fruits. Unfortunately, Sukhorukov (2014) seems to have not considered and discussed other original and representative specimens of C. acerifolium which at the time of his lectotypification were still preserved and available at KW, those kept on loan at H (see Uotila & Lomonosova 2016), as well as some other specimens from LE (at least two other specimens annotated at LE by Mosyakin in 1990 as possible iso(lecto)types).

The lectotype designation made by Sukhorukov (2014) was accepted by Uotila & Lomonosova (2016). However, all these authors failed to notice or recognize the effective lectotypification of the species already done by Dvořák (1987). His lectotypification was based on a specimen from KW at that time sent on loan to BRNU. This specimen was cited (as “Type: ‘ Chenopodium acerifolium Andrz. … Ins. Borysthenicis, Kiev A. 38.’ KW”: Dvořák 1987: 562) and illustrated in Dvořák’s article. He used the word “type” both in the text and on the photograph of the herbarium specimen ( Dvořák 1987: 562, 563, Fig. 1 ). According to Art. 7.10 of ICN ( McNeill et al. 2012), this evidently constitutes a valid lectotypification of the species name. Unfortunately, the specimen selected by Dvořák as the lectotype of C. acerifolium is probably now lost and I have not traced it in KW and BRNU. I sent a request for information to Jiří Danihelka (Curator of BRNU), who informed me that he was able to find in BRNU only a small envelope with a few loose seeds from the lectotype and “…this suggests to me that the specimen had been sent back to Kyiv, indeed. Still, I cannot guarantee this because it may be filed by mistake anywhere in one of more than 100 boxes with Chenopodium specimens [of Dvořák’s collection—S.M.]. Apart from these fragments, there are no specimens from abroad labeled as C. acerifolium here at BRNU” (J. Danihelka, pers. comm. dated 13 September 2016). There are records at KW indicating that some specimens sent by Dvořák from BRNU have been received once. Checking of this information demonstrated that those were duplicates of specimens collected and identified by Dvořák. No positive information about the return of the loan has been traced. Probably the loan of KW specimens of C. acerifolium was sent back to KW from BRNU, but either has been lost in mail or arrived to Kiev and was misplaced in the vast collections of KW. If found (in KW or BRNU), the specimen selected by Dvořák should be considered the non-supersedable lectotype of C. acerifolium .

It is not evident from the label of the lectotype selected by Sukhorukov (2014) if the plant was actually collected or identified by Andrzejowski. The specimen has only a curatorial label (definitely not by hand of Andrzejowski or Besser) with the following text: “Herb. Fischer. Chenopodium acerifolium Andrz. In ins. Borystheni Kiioviae. Herb. W. Besser”. No collection date (year) and collector name are provided. Thus, there is no reliable proof that the specimen selected as the lectotype (Sukhorukov 2014) belongs to original material. However, the present wording of Art. 9.3 and Art. 9.19 of ICN ( McNeill et al. 2012) provides no solid justification for the rejection of this lectotypification. It means that until the specimen selected as the lectotype by Dvořák (1987) is found, the selection of a lectotype by Sukhorukov, unfortunately, should stand.

As indicated above, this specimen from LE lacks fruits and “is only flowering” ( Uotila & Lomonosova 2016: 235). However, morphological characters of fruits are crucial for taxonomy of Chenopodium , as it was emphasized by many authors (see e.g., Iljin & Aelen 1936, Aellen 1960–1961, Sukhorukov & Zhang 2013, Sukhorukov 2014). Considering the possible presence of several taxa (segregate species and probably also infraspecific entities) and possible hybrids in the group containing C. acerifolium , well-developed fruits are important for precise identification of the plants, especially those considered as type specimens. Thus, in my opinion, the plant selected as a lectotype by Sukhorukov (2014) is not properly diagnostic of and representative for the species. Consequently, the epitype is proposed here following Art. 9.8 of ICN ( McNeill et al. 2012), a specimen from the Besser memorial collection at KW collected and annotated by Andrzejowski, with a handwritten original description on the label.

Figures

FIGURE 1. Epitype of Chenopodium acerifolium Andrz. (KW-001002780!).