(126) Request for a binding decision on whether <i>Silene</i> × <i>isabeliae</i> P.P. Ferrer &amp; al. and <i>S. isabellae</i> Selvi &amp; E. Bianchi ( <i>Caryophyllaceae</i> ) are sufficiently alike to be confused

(126) Silene ×isabeliae P.P. Ferrer & al. (‘isabelae’) (2015) [Angiosp.: Caryophyll.] Silene isabellae Selvi & E. Bianchi (2023) [Angiosp.: Caryophyll.] Silene ×isabeliae was described by Ferrer-Gallego & al. (in Fl. Montiber. 60: 104. 2015, ‘isabelae’) from the spontaneous cross between S. diclinis (Lag.) M. Laínz and S. latifolia Poir., in the Botanic Garden of Valencia (Spain), where both parent species were cultivated. The epithet honors the Spanish botanist Dra. Isabel Mateu Andrés, teacher and curator of the Botanical Garden of Valencia in 2015. The holotype of this name is preserved at VAL (with barcode VAL 221326) with an isotype at BC (barcode BC-879430). The existence of the already Latinized epithet elisabethae within the same genus (S. elisabethae Jan in Flora 15: 177. 1832, ‘elisabetha’) prompted the authors to adopt the epithet isabeliae, based on the non-Latinized name Isabel, but initially as ‘isabelae’ contrary to Art. 60.8(b) of the Code (Turland & al. in Regnum Veg. 162. 2025). Selvi & Bianchi (in PhytoKeys 227: 124. 2023) described Silene isabellae from a wild plant occurring in the Skënderbëut Mountains, central Albania. The publication states that “this species is dedicated to the first author's wife, for her continuous support and advice during many botanical trips”. Her name is presumably Isabella, already in Latin, permitting the spelling adopted for the epithet (Art. 60.8 & Rec. 60C.1). The holotype is preserved at FI (barcode FI068201), and several isotypes are deposited in other herbaria (e.g., G, K, TIR). Both names, Isabel and Isabella, are derived from Elisabetha or Elisabeth (Latin genitive elisabethae; see ICN Rec. 60C.1), or λισάβετ (Elisábet) in Greek. Isabel is the common form in Spanish and Isabella that in Italian. However, as Isabel is not latinized, the genitive form, as provided by Art. 60.8(b), is isabeliae whereas Isabella is the Latin form of the name and so the genitive is isabellae, as provided by Art. 60.8 & Rec. 60C.1. The ending derived from Isabel that is neither Greek nor Latin nor for which a well-established Latinized form exists, has sometimes been written, contrary to Art. 60.8(b), as ‘isabelae’ instead of isabeliae (see, e.g., Soria & Zardini in Candollea 46: 537. 1991; Dodson & Hirtz in Dodson, Native Ecuadorian Orchids 5: 1183. 2004; Mytnik-Ejsmont, Monogr. Polystachyinae: 194. 2011; Chiron & Xim. Bols in Richardiana 13: 110. 2012; Ferrer-Gallego & al., l.c.). Both the nothospecies, Silene ×isabeliae, and the species, S. isabellae, are taxonomically accepted, and their names are in current use. The names were published relatively recently and, so far, have been rarely cited (see, e.g., Benito in Bol. Asoc. Herb. Ibero-Macaronés. 18: 68. 2021). Both are included in the main nomenclatural databases (e.g., The International Plant Names Index [IPNI] and Plants of the World Online [POWO-1, POWO-2]). However, their close similarity often causes confusion in searches and databases. For instance, a search in Google Scholar for “Silene isabellae” also retrieved results for Silene isabeliae. In this context, I consider that proposing a new name for Silene isabellae would cause less nomenclatural instability than the recurrent confusion between these two names. We hereby request a binding decision under Art. 53.4 of the ICN as to whether the names Silene ×isabeliae P.P. Ferrer & al. and Silene isabellae Selvi & E. Bianchi are sufficiently alike to be confused and thus should be treated as homonyms. Should they be considered homonyms, Silene isabellae Selvi & E. Bianchi would require a replacement name. I am grateful to Prof. John McNeill and Dr. John Wiersema for their advice, assistance, and insightful comments, which have contributed to improving this proposal.