Euphorbiaceae

Delprete, Piero G., 2016, Giovanni Casaretto: a short biography and his botanical collections in Brazil and Uruguay, Phytotaxa 253 (1), pp. 27-47 : 39-40

Euphorbiaceae

Croton casarettoanus (as “ casarettianum ”) Vis., Orto Bot. Padova 73, 137. 1842.— Croton casarettoanus Müll. Arg. in DC., Prodr. 15(2): 628. 1866, nom. superfl.— Croton rhamnifolius (Kunth.) Müll. Arg. var. casarettoanum (Vis.) Müll. Arg. in Mart. et al. (Eds.), Fl. Bras. 11(2): 179. 1873. Type: Brazil. Bahia [Cachoeira]: “Prov. Bahiensis prope Cachoeira”, s.d. [January–February 1840], Casaretto Herb. No. 2085 (neotype, G-DC barcode G00312260!, here designated).”

Tentatively accepted name: Croton casarettoanus Vis.

Visiani (1842) described Croton casarettoanus (as “ casarettianum ”) Vis. from material cultivated in the greenhouses of the Botanical Garden of Padua, from seeds sent to him by Casaretto. Müller Argoviensis (1866: 628), probably unaware of Visiani’s publication, described Croton casarettoanus Müll. Arg. , which is a superfluous name. After a careful search at PAD, no specimen of Croton casarettoanus was found. Most likely Visiani prepared the description of this species from fresh material but did not make any herbarium specimen. As Visiani (1842: 137–138) and Müller Argoviensis (1866: 628) used the same name, the latter being superfluous, described the species from material originally from Bahia, Brazil, and the descriptions are comparable, Casaretto Herb. No. 2085 at G-DC is here designated the neotype of Croton casarettoanus Vis.

Croton casarettoanus was treated by Müller Argoviensis (1873: 179) as a variety of Croton rhamnifolius (Kunth) Müll. Arg. and was listed as a synonym of Croton heliotropifolius Kunth in World Checklist of Selected Plant Families (WCSP 2016). In Cordeiro et al. (2016) is stated “Riina 02/04/2010: There is still doubt about the accepted name (either C. heliotropifolius or C. conduplicatus [Kunth])” and C. rhamnifolius is treated as a synonym of C. heliotropifolius ; while C. casarettoanus is not present in their checklist. Therefore, C. casarettoanus Vis. is here treated as a tentatively accepted name, pending future revisionary studies that will hopefully clarify its identity.