Erythranthe guttata

Erythranthe guttata (DC.) G.L. Nesom (syn.: Mimulus guttatus DC.) (N-Am.) – A rare but much increasing, locally naturalized or locally invasive escape from cultivation. Apparently first documented from Biourge (Bertrix) where it was found since 1953 and repeatedly confirmed afterwards (see also van Rompaey & Delvosalle 1978). Subsequently also seen in Martilly in 1971 and since 1985 in Bouillon. However, by far most records are fairly recent. In an increasing number of localities it is known since quite a long time now and obviously naturalized. This holds true, for instance, for Parc de Woluwé (Brussels, at least since 1994; Saintenoy-Simon 1998) and several different riverlet valleys in Wallonia: riverlet Ywoigne (Saintenoy-Simon 2008), riverlet Haute-Vierre near Saint-Médard (with historical as well as recent records). Most other Walloon records seem recent. In Flanders perhaps slightly rarer but also increasing, especially in some river valleys (Leie, Maas, Schelde; see Verloove 2002, Verloove 2006).

Erythranthe guttata usually grows by ponds and rivers, in marshland and other damp places. For quite a long time it was considered non-invasive but at least in some places it produces lots of viable seed and seems to be a treat for native waterside vegetation. Additional information on its invasive behaviour in Belgium is available here: Information for the whole of Europe was gathered by Tokarska-Guzik & Dajdok (2010).

Most populations seen so far seem to correspond with genuine Erythranthe guttata: 100% fertile plants with corollas with unspotted lobes and more or less closed throat. However, at least one hybrid has been reliably recorded in Belgium, Mimulus xrobertsii Silverside (Erythranthe guttata x lutea). It is a common and widely dispersed plant in the British Isles (Silverside 1990, Stace 2010) and possibly overlooked in Belgium. It is more or less intermediate between both parents. It was recorded in 1991 as an escape in the Wespelaar arboretum in Haacht.

In Shetland plants with larger corollas and a wider throat have been observed. These proved to have a similar genome like other populations of E. guttata but twice as many chromosomes; they were tetraploids in stead of diploids (Simon-Porcar & al. 2017).


Selected literature:

Adolphi K. (1995) Neophytische Kultur- und Anbaupflanzen als Kulturflüchtlinge des Rheinlandes. Nardus 2: 272 p.

Allen W.R. & Sheppard P.M. (1971) Copper tolerance in some Californian populations of the monkey flower. Mimulus guttatus. Proc. Roy. Soc., B 177(1047): 177-196.

Arathi H.S. & Kelly J.K. (2004) Corolla morphology facilitates both autogamy and bumblebee pollination in Mimulus guttatus. Int. J. Pl. Sci. 165: 1039-1045.

Dole J.A. (1992) Reproductive assurance mechanisms in three taxa of the Mimulus guttatus complex (Scrophulariaceae). Amer. J. Bot. 79(6): 650-659.

Galunder R. (1989) Soziologische Bemerkungen zu Vorkommen von Mimulus guttatus an Talsperren des Süderbergland. Tuexenia 9: 55-56.

Griffiths A.J.F., Carey K. & Ganders F.R. (1982) Anthocyanin polymorphisms in Mimulus guttatus. Canad. J. Bot. 60: 1625-1628.

Grunwald H. (1996) Über weitere Vorkommen der Gelben Gaukterblume (Mimulus guttatus DC.) in Sauerland. Dortmunder Beitr. Landeskde. 30: 7-12.

Hejda M. & Pyšek P. (2008) Estimating the community-level impact of the riparan alien species Mimulus guttatus by using a replicated BACI field experiment. In: Rabitsch W., Essl F. & Klingenstein F. (Eds.), Biological Invasions – from Ecology to Conservation. Neobiota 7: 250-257. [available online at:]

Hughes K.W. & Vickery R.K. (1975) Evolutionary divergence in closely related populations of Mimulus guttatus (Scrophulariaceae). Great Basin Nat. 35(2): 240-244.

Kiang Y.T. (1973) Floral structure, hybridization and evolutionary relationship of two species of Mimulus. Rhodora 75(802): 225-238.

Kiang Y.T. & Hamrick J.L. (1978) Reproductive isolation in the Mimulus guttatus-M. nasutus complex. Amer. Midl. Naturalist 100: 269-276.

Koopman K.R., Beringen R., Collas F.P.L., Matthews J., Odé B., Pot R., Sparrius L.B., van Valkenburg J.L.C.H., Verbrugge L.N.H. & Leuven R.S.E.W.  (2012) Knowledge document for risk analysis of the non-native Monkeyflower (Mimulus guttatus) in the Netherlands. Radboud University Nijmegen: 46 p. [available online at:]

Lange U. (1997) Mimulus guttatus im Bereich der Fuldaaue bei Fulda (5424/13). Hessische Floristische Briefe 46(1): 9-12.

Lange U. (1998) Aktuelle Verbreitung von Mimulus guttatus im Bereich des osthessischen Berglandes (Stand 1997). Hessische Floristische Briefe 47(1): 20.

Lindsay D.W. & Vickery R.K. Jr. (1967) Comparative evolution in Mimulus guttatus of the Bonneville Basin. Evolution 21: 439-456.

Marhold K. (1999) Je okolie Kremnice miestom najstaršieho výskytu čarodejky škvrnitej (Mimulus guttatus DC.) na Slovensku? [Kremnica - the oldest place of occurrence of the Common Monkey Flower (Mimulus guttatus DC.) in Slovakia?]. Bull. Slov. Bot. Spoločn. 21: 63-67.

Matthews J., Beringen R., Collas F.P.L., Koopman K.R., Odé B., Pot R., Sparrius L.B., van Valkenburg J.L.C.H., Verbrugge L.N.H. & Leuven R.S.E.W. (2012) Risk analysis of the non- native Monkeyflower. (Mimulus guttatus) in the Netherlands. Radboud University, Wageningen: 32 p. [available online at:]

Mukherjee B.B. & Vickery R.K. (1962) Chromosome counts in the section Simiolus of the genus Mimulus (Scrophulariaceae), 5. The chromosomal homologies of M. guttatus and its allied species and varieties. Madroño 16: 141-155.

Nesom G.L. (2012a) Taxonomy of Erythranthe Sect. Simiola (Phrymaceae) in the USA and Mexico. Phytoneuron 2012-40: 1-123. [available online at:]

Nesom G.L. (2014) Further observations on relationships in the Erythranthe guttata group (Phrymaceae). Phytoneuron 2014-93: 1–8. [available online at:]

Robertson A.W., Diaz A. & Macnair M.R. (1994) The quantitative genetics of floral characters in Mimulus guttatus. Heredity 72(3): 300-311.

Saintenoy-Simon J. (1998) On nous écrit, on nous communique… Adoxa 20-21: 62.

Saintenoy-Simon J. (ed.) (2008) Trouvailles floristiques récentes (2006-2007. Adoxa 59: 17-51.

Silverside A.J. (1976) Mimulus guttatus, M. luteus and their hybrid. Watsonia 11(2): 182.

Silverside A.J. (1990) A new hybrid binomial in Mimulus L. Watsonia 18(2): 210-212. [available online at:]

Simon-Porcar V.I., Silva J.L., Higgins J.D. & Vallejo-Marin M. (2017) Recent autopolyploidisation in a naturalized population of Mimulus guttatus (Phrymaceae). Botanical Journal of the Linnean Society 185(2): 189-207. [available online at:]

Stace C. (2010) New flora of the British Isles, 3th ed.: XXXII + 1232 p. Cambridge University Press.

Tokarska-Guzik B. & Dajdok Z. (2010) NOBANIS – Invasive Alien Species Fact Sheet – Mimulus guttatus. Online Database of the European Network on Invasive Alien Species. [available online at:]

Truscott A.M., Palmer S.C.F., Soulsby C. & Hulme P.E. (2008a) Assessing the vulnerability of riparian vegetation to invasion by Mimulus guttatus: relative importance of biotic and abiotic variables in determining species occurrence and abundance. Diversity & Distributions 14(2): 412-421.

Truscott A.M., Palmer S.C.F., Soulsby C., Westaway S. & Hulme P.E. (2008b) Consequences of invasion by the alien plant Mimulus guttatus on the species composition and soil properties of riparian plant communities in Scotland. Perspectives in Plant Ecology, Evolution and Systematics 10(4): 231-240.

Truscott A.-M., Soulsby C., Palmer S.C., Newell L. & Hulme P.E. (2006) The dispersal characteristics of the invasive plant Mimulus guttatus and the ecological significance of increased occurrence of high-flow events. Journal of Ecology 94(6): 1080-1091. [available online at:,%201080-1091.pdf]

Van Kleunen M. (2007) Adaptive genetic differentiation in life-history traits between populations of Mimulus guttatus with annual and perennial life-cycles. Evolutionary Ecology 21: 185-199.

Van Kleunen M. & Fischer M. (2008) Adaptive rather than non-adaptive evolution of Mimulus guttatus in its invasive range. Basic and applied ecology 9(3): 213-223.

Van Rompaey E. & Delvosalle L. (1978) Atlas de la flore belge et luxembourgeoise. Ptéridophytes et Spermatophytes. Commentaires. Jardin Botanique National de Belgique, Meise: 116 p.

Verloove F. (2002) Ingeburgerde plantensoorten in Vlaanderen. Mededeling van het Instituut voor Natuurbehoud n° 20: 227 p.

Verloove F. (2006) Mimulus guttatus. In: Van Landuyt W., Hoste I., Vanhecke L., Van den Bremt P., Vercruysse W. & De Beer D., Atlas van de flora van Vlaanderen en het Brussels gewest. Instituut voor Natuur- en Bosonderzoek, Nationale Plantentuin van België en Flo.Wer: 591.

Vickery R.K., Crook K.W., Lindsay D.W., Mia M.M. & Tai W. (1968) Chromosome counts in section Simiolus of the genus Mimulus (Scorphulariaceae), 7. New numbers for M. guttatus, M. cupreus and M. tilingi. Madroño 19: 211-218.

Waser N.M., Vickery R.K. Jr. & Price M.V. (1982) Patterns of seed dispersal and population differentiation in Mimulus guttatus. Evolution 36(4): 753-761.

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith