Amaranthus blitoides var. nanus (Moq.) Iamonico, 2022

Hassan, Walaa A., Al-Shaye, Najla A., Alghamdi, Salma, Korany, Shereen M. & Iamonico, Duilio, 2022, Taxonomic revision of the genus Amaranthus (Amaranthaceae) in Saudi Arabia, Phytotaxa 576 (2), pp. 135-157 : 147

7b. Amaranthus blitoides var. nanus (Moq.) Iamonico , comb. nov.

≡ Amaranthus blitum var. nanus Moq., Prodr. [A. P. de Candolle] 13(2): 263. 1849

Type (lectotype designated by Iamonico 2016c: 91):— SAUDI ARABIA. Ad cisternas Dschedda Arab feliz, 02 January 1836, Schimper 857 (MPU022388!, image of the lectotype available at https://herbier.umontpellier.fr/zoomify/zoomify.php?fichier=MPU022388); isolectotypes at HAL0140219 (image of the isolectotype available at http://141.48.4.202/djatoka/jacq-viewer/viewer.html?rft_ id=hal_0140219&identifiers=hal_0140219), M0241403! (image at https://plants.jstor.org/stable/viewer/10.5555/al.ap.specimen. m0241403?loggedin=true) and M0241404! (image at https://plants.jstor.org/stable/viewer/10.5555/al.ap.specimen.m0241404) .

Description:— Similar to var. blitoides but smaller, i.e. 2.0– 4.5 cm tall.

Phenology:— Flowering time january.

Habitat and elevation:— Human-made habitat, around the sea level.

Chromosome number:— Not still counted.

Alien status:— Native (endemic?) to Saudi Arabia.

Occurrence in Saudi Arabia ( Fig. 9 ):— This species was firstly published for Saudi Arabia by Iamonico (2016c: 91–92; see below “TAXONOMIC NOTES”), sub Amaranthus blitum var. nanus Moq. on the basis of an old Schimper’s collection in Makkah (lectotype). No further finding was done during the filed surveys .

Taxonomic notes:— Iamonico (2016c: 91) lectotypified the name Amaranthus blitum var. nanus on a specimens preserved at MPU (barcode MPU022388). We found further three specimens at HAL (barcode HAL0140219) and M (barcodes M0241403 and M0241404) which can be considered as the isolectotypes, here published for the first time.

Concerrning the identity of Amaranthus blitum var. nanus, Iamonico (2016c: 91–92) proposed to synonymized it with A. blitoides based on characters of flowers. However, no discussion was provided by Iamonico (2016c: 91–92) regarding the generative characters. Based on the examination of the types of A. blitum var. nanus , and the comparison with specimens and living plants examined by one of us (DI) during the last 15 years, Moquin-Tandon’s variety appear to be very small, i.e. 2.0– 4.5 cm tall, whereas A. blitoides s.str. is at least 10–20 cm tall (see also Akeroyd 1993, Bao et al. 2003, Mosyakin & Robertson 2003, Bayón 2015, Iamonico 2015, Atlas of Living Australia 2022). Waiting further studies (floristic and molecular ones could be useful), we think that this taxon should be maintained as separate for the moment, at least at variety rank . Lacking a combination under A. blitoides , we here propose a nomenclatural change.

Specimina visa selecta:— SAUDI ARABIA, Makkah, Ad cisternas Dschedda Arab feliz, 02 January 1836, Schimper 857 (MPU022388!) ;

Figures

FIGURE 9. Map of Amaranthus blitoides var. nanus.