Last year during my Death Valley trip, Cryptanthas drove me crazy. There are something like 120 different species, many of which can only be reliably distinguished by examining the minute nutlets.
I saw plenty of Cryptanthas in Anza-Borrego, too, and decided not to bother much with them. Neat little flowers, but I would just have to accept that I wouldn’t be able to identify them fully.
Then there were the Phacelias. I saw plenty of them, too. Turns out there are about 170 species of Phacelia in North America. Not all of them are found in the Sonoran Desert, of course, but enough of them are.
Like Cryptanthas, the Phacelias are notoriously tricky to identify. I spent hours poring over botanical descriptions but my pictures contain only so much information, and often not the right sort. I didn’t get very far.
I gave up when I discovered that there’s a species named Phacelia cryptantha.
While researching these plants, I tripped across another issue. Seems that authorities don’t quite agree on which family to place the genus Phacelia in. At one time, there were two separate but closely related families, Boraginaceae (borage) and Hydrophyllaceae (water-leaf).

Pholistoma membranaceum, Hydrophyllaceae. Unless it’s Boraginaceae. Or the Hydrophylloideae subfamily of Boraginaceae.
Recent research has resulted in the Hydrophyllaceae being considered a subfamily of the Boraginaceae, called Hydrophylloideae. Not all authorities recognize this distinction, though, and research is ongoing. It’s another one of those areas of taxonomic uncertainty.
In an attempt to make sense of all this, I went through several books* to get good technical descriptions of the two families’ characteristics, and came up with this chart:
Boraginaceae | Hydrophyllaceae | |
form: | forbs; rarely shrubs or trees | forbs; rarely subshrubs |
overall rough textured, hairy | overall small, hairy | |
leaves: | alternate | alternate; rarely opposite |
simple | simple, sometimes compound | |
no stipules | no stipules | |
often entire | mostly lobed, rarely entire | |
coarsely hairy | often hairy or stiff-hairy | |
inflorescence: | helicoid or scorpioid cyme | scorpioid cymes or flowers borne singly |
flowers: | often blue or white | mostly blue, purple, white |
regular (radially symmetrical) | regular (radially symmetrical) | |
bisexual | bisexual | |
5 sepals, separate | 5 sepals, separate or fused | |
or deeply cleft to appear separate | or deeply cleft to appear separate | |
5 petals, fused | 5 petals, fused, often w/ appendages inside | |
5 stamens fused to corolla, alternate with petals | 5 stamens fused to corolla, alternate with petals | |
? | nectary disk present | |
anthers w/ longitudinal slits | anthers w/ longitudinal slits | |
2 carpels, united, often 2 lobed | 2 carpels, usually united | |
locules 4, usually | 1-2 locules | |
ovules 1 per locule | ovules 2 – many | |
ovary superior | ovary superior | |
style 4-lobed | style 2-lobed | |
stigma 2 lobed | stigma capitate | |
fruit | drupe or nutlets | capsule |
I’m not sure it helped, but it was an interesting exercise.
Speaking of Phacelias, three of them are native to the Maryland Piedmont. Yesterday I found one blooming profusely and one of the others budding up. More on them in a few days.
*Botany in a Day, Thomas J. Elpel
Contemporary Plant Systematics, 3rd. ed., Dennis W. Woodland
How to Identify the Flowering Plant Families, John Philip Baumgardt
Photographic Atlas of Botany and Guide to Plant Identification, James L. Castner
Nice job.
This sounds like a botanist paradise.
Ambiguity between species is always a problem. Sometimes it may be impossible to tell the difference between different species at certain phenological stages.
It is a botanist’s paradise – for a few weeks at a time, every ten years or so.
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