Phyllanthus claussenii Müller Argoviensis (1863: 40)

Mendes, Jone Clebson Ribeiro, Silva, Marcos José Da, Pereira-Silva, Rafaela Alves, Sales, Margareth Ferreira De & Athiê-Souza, Sarah Maria, 2021, Typifications and a new synonym in Phyllanthus sect. Phyllanthus subsect. Clausseniani (Phyllanthaceae), Phytotaxa 483 (2), pp. 160-168 : 162-163

1. Phyllanthus claussenii Müller Argoviensis (1863: 40) .

Lectotype (designated here): — BRAZIL. Minas Gerais: In Brasilia prov. Minas Geraës , L. Riedel 1364 ( G00435002 !, isolectotypes K000573056 !, NY00273060 !, P00608959 !, W0051441 ! ).

Phyllanthus claussenii var. oblongifolius Müller Argoviensis (1873: 61) . Lectotype (designated here):— BRAZIL. Minas Gerais: Riacho Fundo, 1834, L. Riedel 1364 (G00435002!, isolectotypes K000573056!, NY00273060!, P00608959!, W0051441!).

Müller Argoviensis (1863) cited Claussen s.n. and Riedel 1364, both from Minas Gerais State, Brazil, without mentioning their depositary herbaria. Webster (2002) mistakenly designated Claussen 1530, deposited in the W herbarium, as the lectotype because it was one of the materials cited by Müller Argoviensis (1873). Webster (2002) considered that decision necessary because there was no mention of a collection number in the protologue. However, the specimen chosen as a lectotype was not part of the original collection, does not adequately represent the species, and does not comply with the protologue because it does not contain staminate flowers - which are crucial for the recognition of the species. Phyllanthus claussenii can be differentiated from the other species in the subsection as a densely branched shrub (vs. herbs or subshrubs), with staminate cymules with up to 6 flowers (vs. 1˗3), and staminate and pistillate flowers having 6 sepals (vs. mostly 5). We therefore decided to reject the lectotypification proposed by Webster (2002) as it causes ambiguities regarding the correct identity of the species, especially in relation to P. subemarginatus . The two species are vegetatively similar, and the characters that differentiate them are associated with the pistillate and staminate flowers. We therefore chose Riedel 1364, deposited in G herbarium (G00435002; Fig. 1 ), as it is in conformity with the protologue by presenting leaves, flowers, and fruits in good condition, and is held in the herbarium where Müller worked.

Phyllanthus claussenii var. oblongifolius was described by Müller Argoviensis (1873) based on the Riedel 1364 collection from “ Habitat in ripa rivi Riacho Fundo, prov. Minas Geraës ”, although the depositary herbarium of the type was not mentioned. The original specimens were located in the G, K, NY, P and W herbaria. Although the specimens are quite fragmented, we chose the collection at G (G00435002!; Fig. 1 ) as a lectotype because that was the main herbarium of Müller Argoviensis and its morphology is compatible with the protologue description. Phyllanthus claussenii var. oblongifolius then becomes a homotypic synonym of P. claussenii (ICN Rec. 26A.1).

Figures

FIGURE 1. Lectotype of Phyllanthus claussenii and P. claussenii var. oblongifolius at the Conservatoire et Jardin botaniques de la Ville de Genève (Switzerland), specimen G00435002.