Unidentified lilac flower

[poschiavanus]

Found this yesterday, went back today having glanced at my books last night, when I think I got an ID, but now can't find the description:



5-petalled flower about 12 mm across, with a corolla tube. Apparently 2 feathery stigmas, 10 stamens, 5 of which lack anthers. Sepals are blunt with greenish midrib but more translucent wide margins greenish at base, but concolourous with petals at apices. There appears to be an epicalyx with long green midrib and wide scarious margins. Small number of stem leaves which are linear and opposite.

This is annoying me because I thought I had the ID because I went back to check the stamens specifically. Please help me overcome this mental block

Posch

PS. Sorry for image quality.

[diggleken]

Well, I'll start..........Flax?
Cheers
Ken

[Hedera]

Most likely Perennial flax which has blunt sepals.

[Tiggrx]

It is something in the family Caryophyllaceae - probably a Silene sp

[poschiavanus]

I'm more or less convinced now that it's a Stork's-Bill Erodium (the 10 stamens half fertile/half not). Whether its just an aberrant flower, or a garden escape, I don't know. However, I started with the assumption that it was a flax, and I spent a lot of time trying to make it fit a Carophyllaceae genus.

Despite the presence of a wasps nest I'll have to have a search for the basal leaves.

It has caused me to carefully studying various Geranium flowers in the garden. This has made me realise how superficially I look at familiar flowers.

Thanks to one and all.

[Dorts]

I have looked at all of the suggestions but I cannot place this anywhere in our native flora.
Wrong colour for Flax, definitely not Geranium, agree it looks a bit like a Silene but which one, none seem to fit.
I do notice what looks like an Acanthus sp. growing behind this plant, so I wonder if it is the result of some garden 'throw-outs' or perhaps it's an area that was recently cultivated?
Dorts.

[poschiavanus]

Dorts comments have caused me to go back through the books on Carophyllaceae, and I have a reasonable candidate in Petrorhagia, possibly P. saxifraga, although the flowers seem large compared to available descriptions. Gardeners familiar with this and similar species may be able to make further suggestions.

The plant behind is the rosette of a ragwort, rather green compared with others nearby. I'll add a picture of the location to give a better feel of scale etc, once I've downloaded them.

The flower is growing in a short width of grass which surrounds ditches or moats of buildings. The ditches form part of a heat-pump system and were deliberately planted with a pretty good selection of native plants (e.g., plenty of Pondweed, Marsh Marigold, Greater Spearwort, Water Cress, Water Mint etc). I don't examine these verges as frequently as I should as they seem to sustain a number of plants I associate with lime-rich habitats, such as Kidney Vetch, Wild Marjoram, and Bee Orchids. Most of the time they are mown too frequently to see plants in flower.

Other planting in the area is mainly ornamental shrubs and trees, so unlikely to be a straight garden throw-out. The estate staff work at other sites which do have formal plantings,so they are one possible source. However, the buildings do have green roofs, and this may be another source (P. saxifraga being listed by one supplier)

Posch

[Dorts]

Posch, that's an interest suggestion; Tunic Flower -Petrorhagia saxifraga.
From your discription of the site there is certainly a possibility of a 'garden-plant' of that ilk finding its way there.
I just thought that if the leaves behind were Acanthus rather than Ragwort, it may have helped answer a question.
I certainly think you could be on the right track with Carophyllaceae.
I'll keep looking at possible candidates.
Dorts.

[Hedera]

Found something like it in my Rock garden book - Saxifrage pink, grows about 10 cms high and makes a mat of foliage, flowers pink or white.

[Tiggrx]

I did consider Petrorhagia saxifraga but it's not right. Other than size it usually has paler pink flowers with narrower, notched petals.