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Mills County, Texas; Timberlake Biological Field Station bioblitz
6/24/2023
Aphanostephus skirrhobasis

Large patch of plants. Annuals. Under magnification (40x), at least some achene hairs appear coiled apically, indicating A. skirrhobasis over A. ramosissimus. It is unclear if all achene hairs are coiled this way as even at 40x, it is not always easy to see. In the field, with a 30x pocket scope, I could only tell that some hairs might be apically thickened or possibly hooked and I was unable to capture any of these hairs well via macro lens in the field. Turner's work on Aphanostephus (Taxonomy of the Genus Aphanostephus (Asteraceae-Astereae) - 1984) makes it sound as if this morphology should be clear at 30x magnification, but that was not my experience (though I don't have the best scope). He apparently originally discovered the difference in hair morphology when examining chromosome numbers via meiotic squashes, so it is possible that he was used to seeing them under higher magnification. There is a line drawing in his work which shows the difference in hair morphology, and it shows some differences which I think would only be visible under higher magnification. On the specimens I examined, the achene hairs were on the order of .1mm long.

Turner also mentioned sometimes finding up to three Aphanostephus species "cohabitating" or even "intermixing" in the case of A. skirrohobasis and A. ramosissimus, so while this observation indicates the presence A. skirrhobasis at this particular spot at Timberlake, it does not rule out the possibility of A. ramosissimus elsewhere. It does cast doubt on observations that have been identified to species where the achene hairs have not been examined, which is probably all of them.

I find it curious that the Flora of North Central Texas, which cites Turner's work, does not reference the difference in achene hair morphology, instead using other features which seem difficult to use. The pappus however did seem scaly rather than hairy, though the scales seemed numerous rather than limited to 5 as suggested for A. skirrhobasis.

Mills County, Texas; Timberlake Biological Field Station bioblitz
6/23/2023
Lindernia sp.

Common around this particular seasonal pond.

While I suspect that this might in some way qualify as L. anagallidea, I did not take a close look at all the features, particularly the lower leaves. There has apparently been some disagreement on how to treat forms fitting L. anagallidea. The Flora of North Central Texas treats it as L. dubia var. anagallidea, while noting that some authors recommend lumping it with L. dubia var. dubia. Weakley (2023) lists it as a species, but notes under L. dubia var. dubia that some authors apparently treat them as forms of the same species.

Kerr County, Texas; Kerr WMA
6/13/2023
Zeltnera calycosa

Nice sized patch on north side of road across from one of the informational kiosks. One of a multitude of Z. calycosa specimens I observed throughout the day. This specimen was single stemmed with corolla lobes about 7.5x3.5mm, the tube about 12 mm, and calyx about 10.5mm. The largest leaf, towards the base, was about 15x4.5mm. This specimen was one of the most robust at this spot. Most at this spot were single stemmed from what I could tell, but I definitely saw other spots where the specimens appeared multi-stemmed and some spots where single stemmed plants were growing so close together as to appear to be multi-stemmed.

Bastrop County, Texas; McKinney Roughs
4/19/2023
Linum imbricatum

Patch of plants in light colored sandy soil which seems to have accumulated on a flat part of the mostly downhill Bluff Trail Loop. Distinguished from L. hudsonioides (which occurs in the nearby uplands of the park) by the ciliate margins found on some upper leaves. It was quite difficult to see the ciliate margins. With a 10x loop I could only see what might have been ciliate margins, but also could have been hairs on the adjacent stem. With a 30x pocket microscope, I could see that there were ciliate margins on at least some of the upper leaves (midstem and upwards), but it did not appear that all the margins were ciliate. Photography of these minute cilia was also difficult since I could never tell if they were in focus and they did not respond well to the direct light of the onboard flash.

I arrived at these plants early in the afternoon and within about 45 minutes almost all of the petals had fallen (or popped off in a ring), as they tend to do in these species.

Plants were up to about 11cm. Petal lobes (measured from top center in flower) were about 8mm.

Found this patch based on this recent observation:
https://www.inaturalist.org/observations/155017445

A last note. Although all the plants within about a 5 meter radius appeared to be L. imbricatum, there was an isolated individual in the taller vegetation about 20-30m away which appeared to be L. hudsonioides.