Amaranthus hybridus var. prostratus Moquin-Tandon (1849: 260)

Iamonico, Duilio, 2016, Nomenclature survey of the genus Amaranthus (Amaranthaceae). 5. Moquin-Tandon’s names, Phytotaxa 273 (2), pp. 81-114 : 98

19. Amaranthus hybridus var. prostratus Moquin-Tandon (1849: 260)

Type (lectotype here designated):— FRANCE. Hort. Tolos., 17 September 1844, s. coll . s.n. (P04021941 [digital image!], image of the lectotype available at http://mediaphoto.mnhn.fr/media/1449489930228Tn4GDRt8TksukpAr).

= Amaranthus hybridus Linnaeus (1753: 990) .

Type (lectotype designated by Townsend 1974: 19):— U.S.A. Habitat in Virginia, Herb. Linn. No. 1117.19 (LINN [digital image!], image available at http://linnean-online.org/11645/).

Nomenclatural notes:—According to the diagnosis of the taxon prostratus ( Moquin-Tandon 1849: 260) this variety would represent prostrate forms of Am. hybridus . No specimens or localitites were cited in the protologue. A specimen at P (barcode 04021941) bears some pieces of the same plant whose features match the original description. The label reports “ Amaranthus cauliflorus ? | caspul acerte dehiscens. | an species distincta. | Hort. Tolos. et seminibus subnomine amaranthi cauliflori misis | 1844 Sept. 17 ”. I consider this specimen as part of the original material and I designated it as the lectotype of the name Amaranthus hybridus var. prostratus

Taxonomical notes:—Although the prostrate form of Am. hybridus are not so frequent for Am. hybridus , it sometimes occurs (see e.g., Costea et al. 2001: 949). I also verified prostrate plant on field. I consider this habitus as consequence of mechanical factor (i.e. trampling) and propose to synonymized the Moquin-Tandon’s name with Am. hybridus .