NEVADA NATIVE PLANT SOCIETY
Rare Plant Committee Meeting
NEVADA RARE PLANT WORKSHOP
Thursday, 6 April 2006, Reno

2006 MEMBER COMMENTS
http://heritage.nv.gov/nrpw/commnt06.htm

The following comments on 2006 agenda items were offered by participants and/or non-participants prior to the 2006 Workshop, and were made available at the workshop as a handout to participants. Those unable to attend but with thoughts or information to contribute are especially encouraged to submit them!

Member: James Morefield
Date: 5 April 2006
Comments: Cymopterus ripleyi was discussed at a Workshop 8 or 9 years ago, along with the subspecies of Penstemon bicolor and Glossopetalon pungens, which have very similar taxonomic issues. At the time, I believe we decided to continue recognizing the subspecies of each of these species because 1) most known populations (with a few notable exceptions) contained only one form or the other, not both, and 2) because the subspecies showed different (though overlapping) geographic and ecologic ranges.

For those reasons, the subspecies were considered to be significant genetic components of each species that merited individual conservation concern. In each case, the subspecies are not fully distinct from one another morphologically, geographically, and ecologically; if they were, we might instead be debating whether they are full species, rather than subspecies (which, in my book, are allowed to overlap and intermix somewhat).

The situation for each of these species is certainly a far cry from something like Amsonia tomentosa, in which the two pubescence forms intermix in every population on an individual by individual basis. That sort of variation almost certainly represents alternate alleles of a single gene being expressed, and does not merit any sort of taxonomic recognition. There seems to be something more going on in Cymopterus ripleyi, Glossopetalon pungens, and Penstemon bicolor.

The data we have on Cymopterus ripleyi continues to indicate that populations of var. ripleyi are concentrated in northern Nye County and/or at higher elevations, while those of var. saniculoides are concentrated in central Nye County and/or at lower elevations. And there are certainly some areas and even populations where the two forms overlap.

If the color forms of Cymopterus ripleyi could be shown to occur mixed in the majority of populations of the species, then the Nevada Natural Heritage Program could certainly be convinced to discontinue recognizing the two varieties. Otherwise, we tend to take the conservative road, and assume that such forms are genetically significant to the species for conservation purposes, until it can be shown otherwise.

When debating these sorts of issues, I ask myself the following: would it be possible to nearly or completely eradicate one or the other of the forms involved? And if so, and such an event were imminent, would I be concerned for the survival and genetic integrity of the species as a whole?

In the case of Amsonia tomentosa, I believe the answer would be no on both counts. When the answer to both questions is yes, however, as I believe it would be for Cymopterus ripleyi, Glossopetalon pungens, and Penstemon bicolor, then I want to continue giving taxonomic recognition to such forms, so that they will remain on the conservation radar screen, thereby helping to prevent any such crisis.

Member: Arnold Tiehm
Date: 4 March 2005
Comments: I have seen both collections of Cryptantha insolita and it sure looks like a good taxon to me. The type was collected by Goodding in 1905 and the label is just "Las Vegas". The 1942 collection was by Ripley and Barneby and again just says "Las Vegas". I once asked Rupert about the location. He told me that Las Vegas was just a wide spot in the road in 1942. They stayed at the Sal Sagev (anagram of Las Vegas) Motel and out behind the motel were springs. The Cryptantha was on the deposits from the springs. They also got Calochortus striatus at the same site. I would imagine that a little detective work could turn up a location for the old motel and then a search of the immediate area would tell if the plant is in existence.

Member: Dana York
Date: 17 March 2004
Comments (in part): Sisyrinchium funereum--I question that this species occurs at Ash Meadows. There are no other rare plant correlations between Ash Meadows and Death Valley. This plant only occurs in the springs surrounding the (Death) valley. The populations vary in size (some >100 plants) and seem to be stable, but threats include exotic plants, water extraction, cattle, and burros.

Member: Jason Alexander
Date: 27 April 2003
Comments: With a taxon as complicated as Astragalus lentiginosus, we do not yet know if these small [Nevada var. stramineus] populations with unique morphology are significantly differentiated from the rest of the complex or are they fully intergradient with neighboring varieties. Untested hypotheses abound (including, so far, mine) but no concrete data has ever been researched. It is important to protect the diversity in this variety in either scenario in a population biology context.

If var. stramineus is a full hybrid, or the Nevada populations are hybrids with var. fremontii, these hybrids swarms are an important conduit for genetic diversity of typical var. stramineus. It is likely that var. stramineus will become genetically depauperate and potentially go extinct if this conduit for genetic diversity is severed. In this case, a conservation plan would encompass populations from Toquop Wash (which are distinguishable from typical stramineus only in having slightly smaller flowers) east to the Beaver Dam Wash. These putative hybrids should be considered var. stramineus until genetic data show otherwise.

If var. stramineus is distinct from other varieties of this complex, the population in Toquop Wash is likely the main source for dispersal in Nevada, having the largest and most widespread extant populations. The others around Mesquite are heavily impacted. In addition, the populations around Beaver Dam are also heavily impacted by past and current development. The remote sandy pockets in washes between Toquop Wash and Beaver Dam Wash are important small populations that promote gene flow and the maintenance of diversity in this species. If this hypothesis is correct, loosing these small populations could cause a loss of genetic diversity and the possible extinction of this variety. In any case, var. stramineus is a taxon in need of some mitigation from habitat loss.

Member: Anita Cholewa
Date: 18 March 2003
Comments: For starters, this genus is not an easy one to separate and is fraught with danger for inexperienced botanists. Here's some additional information that might be of help. In the area where these plants occur (southern NV, UT) there aren't too many other species. In fact, Sisyrinchium demissum is the only other one that overlaps in range. (S. bellum is further west and S. halophilum is further northwest -- we've searched extensively and never found these closer). Sisyrinchium demissum, S. funereum, and S. radicatum are all branched species but can be distinguished on the basis of additional bract and floral characters (see table below). The characters are subtle but real. I have done a fair amount of crossing among these [species] and barriers exist. I don't have flowering dates but generally these are all spring to early summer for the particular region.

The Sisyrinchium funereum populations are mostly within Death Valley and thus protected (Furnace Creek near Inn, Sand Springs at north end of Death Valley and the Ash Meadows border area both within -Devils Hole- and outside Death Valley -McGill Ranch and Jackrabbit Springs [maybe this is inside I don't remember]). Populations contain lots of individuals.

The Sisyrinchium radicatum populations are a bit more dispersed, in Clark, Nye, and Lincoln cos. with some also in Washington Co. in UT. Clark: Charleston Mts - Pine Canyon, Charleston Mts - Ash Spring, Spring Mts - Pine Creek, Red Rock Canyon - Calico Basin. Nye: Big Springs (aka Deep Springs) in Ash Meadows, Pahrump Valley. Lincoln: Pahranagat Lakes, Pahranagat Valley - Ash Springs. I can't assess the threats to these populations.

I would be happy to look at your materials [in Nevada herbaria] but I cannot promise a speedy return if more than just a few specimens.

(last updated 24 April 2006) 

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