Papaver commutatum Fisch. & C.A. Mey. (W As., Crete) – An exceptional and ephemeral grain alien (but possibly overlooked). Recorded in 2015 on the abandoned unloading quay for cereals at the Amerikadok in the Antwerp port area.
This species is much reminiscent of Papaver rhoeas and may have been overlooked so far. It has darker red petals, nearly always with a distinct black spot at base (spot sometimes with white margins). Pedicel setae are closely appressed, not patent as in P. rhoeas (f. rhoeas). In f. strigosum (Boenningh.) Rothm. of the latter, setae on pedicels are more or less appressed but always longer and its petals are unspotted (Mowat & Walters 1964). Both species also differ in leaf and capsule characters (see key). Despite this, some authors have considered these two species conspecific. Kadereit (1988) placed them in different groups on morphological and geographical grounds, although molecular data show a closer relationship (Carolan & al. 2006).
Papaver commutatum is a weed in corn fields, vineyards etc. (Kadereit 1988). Outside of its native distribution range it has been recorded as a grain alien. For its spectacular flowers it is also cultivated as an ornamental (Cullen 1995, Jäger & al. 2008). Clement & Foster (1994) provide British records for it as an escape from cultivation and similar records are also available from Scandinavia (Karlsson 2001).
Carolan J.C., Hook I.L.I., Chase M.W., Kadereit J.W. & Hodkinson T.R. (2006) Phylogenetics of Papaver and Related Genera Based on DNA Sequences from ITS Nuclear Ribosomal DNA and Plastid trnL Intron and trnL–F Intergenic Spacers. Annals of Botany 98(1): 141-155. [available online at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2803553/]
Clement E.J. & Foster M.C. (1994) Alien plants of the British Isles. BSBI, London: XVIII + 590 p.
Cullen J. (1995) Papaver. In: Cullen J. & al. (eds.), The European Garden Flora, vol. 4. Cambridge University Press, Cambridge: 105-110.
Jäger E.J., Ebel F., Hanelt P. & Müller G. (eds.) (2008) Rothmaler Band 5. Exkursionsflora von Deutschland. Krautige Zier- und Nutzpflanzen. Springer Verlag, Berlin: 880 p.
Kadereit J.W. (1988) A revision of Papaver L. section Rhoeadium Spach. Notes Roy. Bot. Gard. Edinburgh 45: 225-286.
Karlsson T. (2001) Papaveraceae. In: Jonsell B. (ed.), Flora Nordica, vol. 2. The Bergius Foundation, Stockholm: 340-368.
Mowat A.B. & Walters S.M. (1964, 1993 rev. by Kadereit J.W.) Papaver. In: Tutin T.G. & al. (eds.), Flora Europaea, vol. 1. Cambridge University Press, Cambridge: 247-250 (297-301).