Herbarium specimens - gbif

What is GBIF—the Global Biodiversity Information Facility—is an international network and research infrastructure funded by the world’s governments and aimed at providing anyone, anywhere, open access to data about all types of life on Earth. See: https://www.gbif.org/what-is-gbif

An example of a high resolution image of a herbarium specimen of a high-altitude species:

I trust examination of this close-up, shows you the detail of what can be observed from such pressed specimens - which greatly increases knowledge and understanding of individual species and helps towards reliable plant identification. By comparison, a quick look at a small, single image of a species within a book, does not provide the close-up detail of diagnostic characteristics, often making it impossible to identify with confidence species belonging to difficult-to-identify species, which includes Arenaria.  Yes, it is possible to identify distinctive, common species by 'matching' with poor images but even then, the potential for mistakes is high. 'Flowers of the Himalaya' e.g. is poorly used by both amateur plant enthusiasts and Indian botanists - who falsely treat it as a flora, when in fact, only about 1/10th of the total flora known from the regions of the Himalaya covered, are included as descriptions, line-drawings or photos, so 'matching' with a picture in this book (the content is of a high standard being 99.9% accurate) neglects to consider the missing species. My informal research has shown that most floras, check-lists, articles etc. on flora of the Indian Himalaya are riddled with misidentifications, errors and omissions!

The above image is from 'Flowers of the Himalaya' (Polunin & Stainton, 1984) - whilst showing the typical habit (of an older specimen) well, one cannot distinguish between this and similar species on the basis of this photo; the authors say A.densissima is found on overhanging rock faces (though not exclusively) but it is not straightforward to differentiate this species from A.polytrichoides or A.bryophylla, both which also form mounds at high altitudes - though the latter two may be restricted to the borderlands of and Tibet proper, from Ladakh eastwards whereas A.densissima has only been found from Nepal to Bhutan, presumably in higher rainfall areas, with the smallest flowers.  The main 'Flowers of the Himalaya' has no photo of A.polytrichoides but the Supplement (which few have a copy of) does - its flowers are minute.