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[[NOTE: Three additional (large-sized!) images of this plant (showing more of the flowering stems, and habitus) are available in this companion post on CalPhotos. Check out the "full-size" photos there.

Also, remarks on diagnostic characters (and some descriptive morphology) for Nemacladus morefieldii appear under the this CalPhotos post. ]]

====== Variation in Characters for Nemacladus morefieldii ======

I'm struck by some of the variation in this (lovely) species.

1) Marginal "chevron" markings on upper three corolla lobes: For instance, note how narrow the reddish "chevrons" of the three upper corolla lobes are in the flowers of the plant here...vs. the much wider marginal chevrons in my CalPhotos post referenced above. Similar variation will be seen upon perusing photos of N. morefieldii on iNaturalist, CalPhotos, and CalFlora.

2) Relative sizes of "flanking" and "central" sepals: Another character that is celebrated for "good" N. morefieldii (i.e. in plants that have taken time to read & comply with the circumscription ;;-) is that the "flanking sepals" (= lateral sepals behind, and angled somewhat below, the lateral petals of the upper lip) are appreciable larger than the "central (upper) sepals" (= those alternating with the uppermost corolla lobe, and positioned behind its sinuses). Not only are those flanking sepals typically somewhat longer and (especially) wider than the upper sepals...but usually they're also distinctly more "cupped", and cradle the lateral lobes of the upper corolla lip — i.e. more so than the flanking sepals in flowers of the close congener N. orientalis (which, in addition, has its sepal of more equal size). It's best to have a "from the back" view of a flower to assess the relative sizes of the flanking & central sepals...which I didn't get here. But, in the first photo here, one can see that the flanking sepals in the withering flower at left-center are somewhat wider & longer than its central sepals. This is a nice distinctive character...though it does seem to vary quite a bit.

3) Relative size (or even absence?) of "rod-like processes": Finally, I've been wondering how much variation in size (and perhaps even presence?) occurs for the glistening, translucent, "rod-like processes" at the bases of the two adaxial stamens. In the flowers imaged here I can clearly discern the presence of these rods...whereas in my CalPhotos post here they aren't discernible. I know from experience that getting a photo with those rod-like processes in focus can be very difficult...since in most Nemacladus species these rods are exceedingly tiny, and there's very little "depth-of-field leeway" for one's focal plane at the high-magnification required to image them. But still, I'd think that even if focus is a bit off, there'd be at least a blurry intimation (or ghost-image) of the rods? But maybe not? At any rate, perusing photos of N. morefieldii, it seems like in some flowers the rods appear distinctly present, while in others they appear to be absent. It may be worth checking fresh flowers seen in the field with a hand-lens...to see if they have a fairly consistent presence & size for these rods (i.e. if their seemingly random "presence" and "absence" in photos is truly just an artifact of getting photographic focus just right).

I suppose whether the rods are visible might also be subject to phenology? How long does it take for a Nemacladus flower to fully-develop...to open and unfurl its corolla lobes, for its staminal tube to attain full length and standard position? Do the rods attain full size in bud, or perhaps continue to grow a bit after the flower opens and as it matures...passing from its "male" anther-dehiscing stage through to its "female" stage of stigma receptivity? And how many days does a given flower remain open during this process? One, two, more?

There are always more questions to ponder with these wonderful plants :-)

====== Pollination Biology in Nemacladus ======

I'm especially curious & eager for us to learn more about which groups of insects are effective pollinators of Nemacladus flowers...and details of the pollination processes that occur & their mechanisms (e.g. Campanulaceae is known for its remarkable secondary pollen presentation structures & mechanisms).

For instance, I'd speculate that species with non-resupinate flowers like N. morefieldii (and N. orientalis, N. montanus, N. interior, etc.) would tend to place pollen on the underside of a visiting insect of the appropriate size (i.e. sternotribic pollen placement). And for resupinate-flowered species, I'd guess pollen placement would more likely be on the upperside of an insect visitor's body (i.e. nototribic). But a priori speculation about pollination processes based on flower morphology has often turned out to be off-the-mark. ;-) Careful direct observation & documention of pollinator visits and behavior (and thoughtful, creative experimentation)...though very time-consuming and laborious...is probably the best avenue for making progress on this front.

I also wonder to what extent (and under what conditions) self-pollination may occur in Nemacladus?

The only other plant found growing in the immediate vicinity was a succulent shrub species of Amaranthaceae, Arthraerua leubnitziae. Heavy fog in the morning. Ten miles East, no fog. In this way Welwitschia can be seen to be a relictual species somewhat akin to coastal redwoods of California, both clinging to a narrow strip along the coast of a cold ocean where they can find what they need to survive and in the case of Welwitschia, avoid competition.

I almost can’t believe it myself, but it has to be this. We just went and saw Lewisia maguirei in the Quinn Canyon Range YESTERDAY. About 150 air miles from this location in the Spring Mountains. About 50 plants. South and west facing limestone slope near top of small ridge. We looked at the sepals of 20 flowers, 19 had 3 sepals and 1 had 4 sepals. Plants had 2-3 flowers per inflorescence. :)!

These were blooming all over the area above the Dominguez Canyon, bright spots of yellow opening for one day and then dying, ready for another set to bloom tomorrow. They don't have time for fancy smooth petals, so the wrinkled linen look is in.

A beetle resting in the shade of some petals is par for the course!