Notes on Boraginaceae Identification

This page last modified on 25 March, 2006

Of all the Families shown on this website, several genera in the Boraginaceae are probably the most difficult (if not impossible) to identify using only photographs taken entirely in the field.  See my Notes attached to the first photograph in the series for each of the species regarding rationale for marking the species in this photo key.

In this respect, the greatest problems associate with the "Popcornflowers", of which we have numerous examples in the following genera:

• Cryptantha - 20 species in the SDNHM Checklist by Simpson & Rebman (3rd edition)
• Plagiobothrys - 11 species in the Checklist, one of those having 4 subspecies.
• Pectocarya - 7 species in the Checklist.

To identify these, one requires closeup images of the fruit, known by botanists as nutlets, which range in size from 1 to just a few millimeters along their maximum dimension. In many cases, it's the surface markings of the nutlets that are cited in the botanist's keys as the essential distinguishing features. Generally, botanists use a low powered microscope in making their identifications. In his instructions to the SDNHM PlantAtlas project parabotanists, Jon Rebman emphasizes that in collecting samples of the popcornflower plants for identification (hence inclusion in the PlantAtlas database) samples of the mature fruit are essential.

Until now, having been intimidated by this requirement AND by the small size of the nutlets, I've not been able to get enough photographic evidence to be certain about my photos of the popcornflower plants. That's the reason why I've not yet collected very many photographs of these plants, though they are among the most common wildflowers one sees in the wild throughout San Diego County!!  With a slightly higher quality camera now in hand, I hope soon to get sample photos of the nutlets for inclusion in these pages. Because of the large number of candidate species, it remains to be seen whether it will be worthwhile to build a Multiple-Entry Key for analyzing the species, similar to the one I've included on this website for the Asteraceae.

-- Ken Bowles.