Follow up from this and that. In a seasonal wetland of sorts.

The Cotula coronopifolia group or section can be a very tricky one. Two species in this group that are often confused are C. vulgaris and C. filifolia, whos differences can be rather subtle.

While C. vulgaris is generally described as larger and more robust than C. filifolia, it is also thought to flower a bit later on in the season than C. filifolia - including in localities where they co-occur. In the latest revision of the group (see below text), it is also noted that the disc ovaries and fruits of C. vulgaris are marginally ribbed, while those of C. filifolia are marginally winged.

Unfortunately this will be impossible to discern in most - if not all - iNat observations. In this observation I took to examining these plants from the Kommetjie Lighthouse under a microscope for both identification and in order to paint a clearer picture.

I added a screenshot of the ovary and fruit comparisons between the different species in the group and keyed these out as C. vulgaris for a second time (based on both "obvious" physical features and now the more subtle ones). Although I found that one can actually work out whether the ovaries and/or fruits are ribbed or winged with just the naked eye, it is much clearer with the microscope!

In the attached screenshot (image #11), C. vulgaris disciform floret = C1, C. vulgaris disc floret = C2; C. filifolia disciform floret = D1, C. filifolia disc floret = D2. C. eckloniana = B1,2,3,&4.

Reference:
Powell, R.F.; Boatwright, J.S.; & Magee, A.R. (2014) 'South African Journal of Botany' A taxonomic revision of the Cotula coronopifolia group (Asteraceae) and implications for the conservation statuses of the species. Volume 93. pp. 105-117. Available at: https://www.sciencedirect.com/science/article/pii/S0254629914000507