Brodiaea jolonensis Doesn't Exist In Southern California
Tom Chester and Wayne Armstrong
Table of Contents
Abstract (Summary of Paper)
I. Historical Background
II. Fieldwork
III. Analysis
IV. Conclusions
Authors' note on draft status of this paper
Acknowledgments
References
Abstract
The taxon Brodiaea jolonensis, defined from a type specimen found in Northern California near the town of Jolon, does not exist in Southern California. We have compared samples collected in Monterey in 2004 of true B. jolonensis with samples of "B. jolonensis" collected in Southern California in 2003 - 2005. There are at least twelve significant differences between the two sets of plants, many of them quite obvious, definitively ruling out these plants being assigned to the same taxon.
This conclusion is not surprising. The existence of problems in defining B. jolonensis and B. terrestris ssp. kernensis is apparent internally in the latest monograph on Brodiaea (Niehaus 1971), and becomes obvious in comparing the treatment in a Flora of Southern California (Munz 1974) with Niehaus (1971).
Our investigations have revealed similar problems with the taxon B. terrestris ssp. kernensis, which we are still investigating.
The incorrect assignment of Southern California plants to the name B. jolonensis appears to be historical, resulting from partial steps toward straightening out the Southern California Brodiaea identifications from the time when all the plants were known as B. coronaria. Somewhat inexplicably, Niehaus (1971) failed to properly treat B. jolonensis and B. terrestris ssp. kernensis, although he made some important steps toward doing so. Munz (1974) contributed insight into the division of Southern California Brodiaeas, but ended up defining these two taxa differently than did Niehaus!
It may well be that we have two taxa in Southern California, one called "B. jolonensis" in Munz, but that name cannot be used for them, since our Southern California plants are completely inconsistent with the type specimen for that name.
I. Historical Background
Species in the Broadiaea genus (defined in the narrow sense which excludes Dichelostemma, Triteleia, etc.) have undergone significant change with time. There were eight California species in Jepson (1923, 1925) and in Abrams (1923). Hoover (1939) had ten California species, and a total of 16 taxa. Niehaus (1971) had 15 California species, and a total of 17 taxa in California plus one additional taxon in Oregon.
No monograph on Brodiaea has been published since 1971. The Jepson Manual (1993) and the Flora of North America essentially follow Niehaus, only changing B. leptandara to B. californica var. leptrandra.
The difficulty with this genus is that the corolla is almost identical for many species. The main discriminants of the species are small details of the characteristics of the staminodes and the filaments. Unfortunately, in typical pressed voucher specimens the corolla lobes are usually erect and hide the characters needed for taxonomic study. (The lobes are typically ascending or spreading in live specimens, but quickly become erect after collection.) Only vouchers that have had the flowers split open before pressing are useful specimens for taxonomic study, and collectors rarely appreciate this fact.
Furthermore, some characteristics, such as the orientation of the staminodes, are impossible to study even with good voucher specimens, and other characteristics, such as the ovary color and the shape and length of the staminodes, sometimes change with drying. Since most botanical studies work with vouchers, it is not a surprise that most botanists simply go along with the classification du jour and don't recognize difficulties with that classification.
The rest of this paper will discuss only specimens currently determined as B. jolonensis, henceforth Bj, and B. terrestris ssp. kernensis, henceforth Btk. We will show that none of these specimens can be identified as Bj, since they are very different from Monterey County plants collected near the type locality for Bj. We come to no conclusions here as to what the proper name or names for the Southern California specimens should be; we are currently investigating that topic.
All of the Southern California plants now determined as either taxon were originally called B. coronaria.
Although Bj was published in 1938 and Btk, as B. coronaria var. kernensis, was published in 1939, Btk was recognized as existing only in Kern County until 1971. In 1971, all the B. coronaria plants in Southern California not previously classified as Bj were transferred by Niehaus to Btk.
The problems with these two taxa in Southern California probably result from the historical order in which specimens in Southern California were redetermined as being these taxa.
In particular, when Bj was defined, the short length of the filaments was used as a key characteristic. Since this was one of the few characteristics that could be reliably measured in vouchers, it was only natural that the portion of the B. coronaria population in Southern California that also had short filaments were quickly transferred to that taxon. This taxonomic change seemingly was corroborated because these were all coastal plants, matching the coastal habitat of the type specimen.
(Add in b. elegans australis from 1957. What is its range and discrimination? It apparently wasn't accepted as a valid taxon by munz, but was combined into Btk in JM.)
The transfer of the rest of the Southern California plants from B. coronaria to Btk by Niehaus is somewhat mysterious to us, since Niehaus gives no compelling reason that plants corresponding to B. coronaria var. kernensis should be moved to B. terrestris, and presents no clear evidence that these Southern California plants fit the type specimen of Btk. Worse, the Niehaus 1971 monograph is striking in that it has major errors involving the taxon Btk. Plants corresponding to Btk cannot be keyed out using the Niehaus (1971) key!
The relevant portion of the key as published in Niehaus (1971) is:
B. Flowers 24-38 mm long [leads to B. coronaria]
BB. Flowers 14-24 mm longC. Staminodia leaning inward, margin semi-involute, apex broad and slightly hooded; perianth segments campanulate.-Section Terrestres.D. Scape 0.5-5 cm high; anther connective dentate; ovary green.............. 6. B. terrestris
DD. Scape 6-15 cm high; anther connective entire; ovary light purple. .......7. B. jolonensis
The Niehaus key is only to each species as a whole, with the subspecies being distinguished only with the detailed descriptions.
Yet in the text, Niehaus gives the following properties for Btk: scape 2-20 cm; perianth tube 11-13 mm long, segments 15-20 cm long, which makes the flowers 26-33 mm long assuming the segments (corolla lobes) were erect when measured.
There are thus two major errors in this key, making it impossible to key out specimens of Btk:
- First, flowers 26-33 mm long would key under "B", which leads to B. coronaria;
- Second, scapes of 2-20 cm high clearly don't fit under the Scape 0.5-5 cm high for the key element D that gives B. terrestris.
The most likely hypothesis for the existence of these two egregious errors is that at the time Niehaus made the key, he still had the Southern California plants as B. coronaria var. kernensis. If that was true, his key was then correct. It must have only occurred to him late in the preparation of his monograph to move the Southern California plants from B. coronaria var. kernensis to Btk. After he did that, he never went back to update his key, nor did he supply any reasoning to support that change, leaving the reasons behind this change mysterious.
Almost simultaneously with Niehaus (1971), Munz was writing his Flora of Southern California (Munz 1974). Munz does not reference Niehaus (1971) for his Brodiaea section; instead he refers to Hoover (1939). Interestingly, though, Munz came to the same assignment of the Southern California plants as Niehaus, with the coastal plants with short filaments assigned to "Bj" and the montane plants with longer filaments assigned to Btk. But the two taxa as he describes them are strikingly different!
There are two striking differences between the Munz and Niehaus descriptions of Bj, the lengths of the pedicel and perianth tube. There is very little overlap in the quoted lengths!
In addition, there is no mention by Munz of a key element from Niehaus: ovary light purple. Niehaus emphasizes that Bj is the only species with a purple ovary; all other species have green ovaries. For his "Bj" plants, Munz doesn't mention anything about the ovary being a distinctive color, probably for the excellent reason that the plants in Southern California all have green ovaries. (The Southern California plants sometimes have a faint purple streak, but their overall color is clearly green, very different from plants we collected in Monterey County.)
These differences between the Niehaus "Bj" and the Munz "Bj" are summarized in the following table:
Differences Between The Niehaus "Bj" And The Munz "Bj"
| Characteristic | Niehaus | Munz |
|---|---|---|
| pedicels | 1-4 cm | 2-12 cm |
| perianth tube | 7-9 mm | 8-13 mm |
| ovary color | purple, the only species without green ovaries | not mentioned, probably because the Southern California plants have green ovaries |
These don't sound like the same taxon!
In fact, as we show below, the simple reason behind this inconsistency is that the Southern California plants described by Munz are not consistent with specimens growing near the type specimen for Bj.
II. Fieldwork
Samples were analyzed from the following locations, organized from north to south:
- Trail to Junipero Serra Peak, northwest of Jolon, Monterey County, 1 June 2004 (Photographs)
- Topanga Meadow in the lower Hondo Canyon section of the Backbone Trail, Santa Monica Mountains, coastal Los Angeles County, 17 May 2004 (abbreviated SMM on the plots below)
- Santa Rosa Plateau Ecological Reserve, Vernal Pool Trail, southwest Riverside County, 15 May 2003, 19 May 2004, and 26 May 2005 (abbreviated SRP, with the year tag, on the plots below)
- San Marcos Vernal Pool Area, coastal northern San Diego County, 13 May 2003 and various dates thereafter in both 2003 and 2004 (Photographs)
- Sunrise Highway near Garnet Peak, Laguna Mountains, eastern San Diego County, 15 June 2004 (Photographs)
- Mission Trails Regional Park, coastal southern San Diego County, 17 May 2005
- Otay Mesa, coastal southern San Diego County, 13 May 2004 and 14 May 2005 (Photographs) (called Otay Lakes in the plots below)
All of these specimens have been previously determined as "Bj" by other botanists, except for the plants at the Santa Rosa Plateau and in the Lagunas, which have been determined as "Btk".
III. Analysis
The Monterey County Plants
To us, the most striking result by far from our field work is that the Monterey County plants visually looked different from the Southern California plants, with smaller flowers. A glance inside the corolla immediately showed four striking differences. The first two listed below were features of Bj we had sought for years in Southern California plants called "Bj" and never found.
- First, the ovaries were dramatically, distinctly, and definitely purple, not the green of the Southern California plants.
- Second, the two anther sacs in each stamen are indeed close together, exactly as pictured in Niehaus (1971), unlike the widely-separated anther sacs in Southern California plants.
- A third difference was also obvious and surprised us: the tips of the anther sacs were usually elongate and hooded, unlike the blunt rounded plane tips of the anther sacs for Southern California plants.
- Finally, the anther axis tissue was indeed always entire, unlike the variably-toothed anther axis tissue for coastal Southern California plants.
In other words, there was no doubt at all that the Monterey plants were a different species from the Southern California plants, and fit well the main characteristics of the Niehaus key and drawings. Principal components analysis is not needed here to distinguish them!
Here are pix taken by Wayne that show these dramatic differences:
Bj ovaries and anthers from Monterey County
Ovaries and anthers from Southern California plants
The V-shaped, entire notch of Bj plants from Monterey County, and the close-together anther sacs, from dried anthers
The U- or W-shaped, variably-toothed notch of most coastal Southern California plants, and the widely-separated anther sacs found in all Southern California plants, from dried anthers
Detailed measurements of the Monterey plants reveal additional characters different from any Southern California plant. In total, there are twelve significant differences between the two sets of plants, definitively ruling out these plants being assigned to the same taxon. Differences between species are rarely as obvious or as numerous as the ones seen here. (One has to keep in mind that these differences are generally in small details within the flower, which is why they have escaped notice before.)
The following table summarizes the length characteristics measured from the Armstrong xxx voucher of the Monterey plants, which will be deposited TBD. All measurements are in mm. It should be kept in mind that the table gives minimum ranges for the properties of Bj. More localities should be sampled to definitively obtain the true range.
Measured Lengths Of Monterey Plant Characteristics
| Characteristic | # Measurements | Minimum | Median | Maximum |
|---|---|---|---|---|
| scape | 12 | 70 | 169 | 290 |
| bracts | 5 | 4.7 | 7.5 | 10.5 |
| pedicel | 12 | 12.0 | 51.0 | 94.0 |
| perianth tube | 14 | 5.0 | 7.0 | 9.0 |
| perianth lobes | 14 | 8.3 | 11.5 | 14.5 |
| perianth | 14 | 14.5 | 18.4 | 23.0 |
| staminodes | 10 | 4.3 | 4.6 | 5.2 |
| filament | 3 | 1.2 | 1.4 | 1.5 |
| anther | 9 | 3.2 | 4.0 | 4.1 |
| ovary | 4 | 4.5 | 5.5 | 6.0 |
| style | 4 | 4.5 | 5.0 | 5.5 |
All too commonly, it is somewhat ambiguous as to exactly how some of the measurements reported in floras were made. We made the measurements as follows:
- Scape (peduncle length): only the above-ground portion. Often, when Brodiaea scapes are gathered in the field, a portion of the scape below ground is taken as well. That portion can be distinguished in fresh samples by its white color due to lack of pigment seen in the above-ground portion, and sometimes by a shredding of the below-ground portion.
- Bracts: We measure the longest bract from the tip of the lobe to where its base first becomes distinct from the continuous membranous tissue below the lobes.
- Perianth tube and lobes: We measure the tube from the contact with the pedicel to the first point where the lobes are distinct from the tube. This is obvious in fresh flowers in full bloom, but becomes harder to discern in flowers past full bloom. We measure the lobes in an erect position, not in their typical ascending-recurved position in very fresh flowers, since soon after taking a fresh sample, the lobes become erect. Similarly, we measure the perianth total length with the lobes erect.
- Staminodia: We measure from the apex to the lowest point in the corolla tissue attached to the base of the staminodia. That lowest point is typically halfway to the neighboring stamens.
- Filament: We measured from "the lowest point in the corolla tissue attached to the back of the filament where the filament becomes free from the corolla" to where the anther axis tissue begins. This corolla tissue is often described as wings or a basal widening of the filament.
- Style and Ovary: We take the dividing point to be where the second derivative of the curve tracing the outline of the ovary / style is zero. This is where the curvature at the top of the ovary reverses from curving in toward the axis to curving up toward the style, and is a well-defined point observationally.
Comparison Of The Monterey County Plants To The Values For "Bj" Reported By Niehaus
The following table compares our measurements on the Monterey County plants to the values for "Bj" reported by Niehaus:
Comparison Of The Monterey County Plants To The Values For "Bj" Reported By Niehaus
| Characteristic | Monterey plants | "Bj" from Niehaus (1971) |
|---|---|---|
| Ovary color | purple | purple |
| Width of anther axis tissue | << anther sacs | << anther sacs (from his drawing) |
| Shape of top of anther axis tissue | V-shaped | V-shaped |
| Shape of top of anther sacs | elongate, hooded | rounded, planar (from his drawing) |
| scape | 70-290 mm | 50-150 mm |
| bracts | 4.7-10.5 mm | -- |
| pedicel | 12.0-94.0 mm | 10-40 mm |
| perianth tube | 5.0-9.0 mm | 7-9 mm |
| perianth lobes | 8.3-14.5 mm | 11-18 mm |
| perianth | 14.5-23.0 mm | 18-27 mm |
| staminodes | 4.3-5.2 mm | 5-6 mm |
| filament | 1.2-1.5 mm | 1-2 mm |
| anther | 3.2-4.1 mm | 4-5 mm |
| ovary | 4.5-6.0 mm | 5-6 mm |
| style | 4.5-5.5 mm | 5-7 mm |
In comparing these measurements, one has to remember that Niehaus supposedly included coastal Southern California plants in his summary of the properties of his "Bj". Although at first glance it would seem very surprising that he had done so, due to the obvious purple vs. green ovaries, it turns out that the green fresh ovaries sometimes turn purple when dried! (See Photographs).
With that in mind, the most surprising thing about the comparison is the fact that our measurements of just 12 inflorescences from just one locality have nine characteristics that are outside the range reported by Niehaus! Some of them are dramatically outside the Niehaus range, like a maximum scape length of 29 cm vs. one of 15 cm, and a maximum pedicel length of 9.4 cm vs. one of 4.0 cm. If we hadn't gathered plants from near the type locality, and they didn't have the key features as delineated by Niehaus, we would have been concerned that we had discovered a different species of Brodiaea!
We speculate that Niehaus probably didn't measure very many specimens to obtain his ranges, and in fact may have only measured a handful of plants from near the type locality of Bj, thereby fortunately avoiding contamination from his inclusion of Southern California plants within his Bj category.
Comparison Of The Monterey County Plants To Southern California Plants
The following plots show the comparison of all individual measurements for every flower for the Southern California plants compared to the Monterey plants. Not every Southern California population is in every plot, since some locations only have flowers without the complete inflorescence in earlier samples, obtained when we were primarily just looking for purple ovaries in Southern California.
Although it would be preferable to have samples from many locations near the type locality of true Bj, our samples from a single location are so strikingly different from any Southern California sample that further samples of Bj are not needed for this comparison. Our Southern California samples were collected from a half-normal rainfall year in several habitats, and also from a twice-normal rainfall year in several habitats. If the Southern California plants corresponded to the same taxon, we would expect at least one of our samples to approach any sample of true Bj.
Perianth Lengths
Note the very clear separation of the Monterey County plants from all of the Southern California plants, shown most dramatically in the plots using the median values. The Monterey County flowers fall precisely within the 14-24 mm range for the perianth length given in the Niehaus key for Bj; the Southern California flowers match that range quite poorly with their observed range of 20-30(36) mm. Median values for each population are plotted in the second plot below in each set:
The scatter is much less in the perianth vs lobe length plot because the lobe makes up ~60% of the perianth length, whereas the tube contribues only ~40% of the perianth length.
Ovary and Style Lengths
The ovary and style length correspond closely with the difference in perianth length. The Monterey County plants have a very clear separation from the Southern California plants in the style length, and are also separated in ovary length from all Southern California plants except the Mission Trails plants:
Filament and Anther Lengths
Finally, although some Southern California plants have the same filament lengths as the Monterey plants, the anther size range has no overlap. (This plot poorly represents the 9 anther size measurements for the Monterey population, since only 3 filaments were measured.)
Comparison Of Chromosome Counts
Another piece of evidence showing that the Southern California plants do not fit the taxon Bj comes from chromosome counts. Although we have not done chromosome counts in general, many years ago Wayne had analyzed the chromosome numbers of a hybrid population of Brodiaea in San Marcos, with staminodia that appear intermediate between Bj / Btk and B. filifolia. His results are inconsistent with the claimed chromosome numbers for Bj reported by Niehaus (1971).
Specifically, the tentative sporophyte number of the hybrid is 36 (6n), determined from microsporogenesis. It was probably derived from a cross between tetraploid and octoploid parents. B. filifolia is a tetraploid with a gametophyte number of 12. Btk is an octoploid with a gametophyte number of 24. Bj has haploid and triploid gametophyte numbers of 6 and 18, thus eliminating it as a likely parent. However, because another tetraploid (B. orcuttii) grows nearby, one cannot completely exclude it as a possible parent, even though that possibility is unlikely based on the staminodia. See Wayne's analysis.
Comparison Of Number Of Vascular Strands In The Inner Perianth Lobes
Niehaus reports that in all Brodiaea species, the central vein for the inner perianth lobes is divided into three vascular bundles. Those bundles are further divided into differing numbers of strands, depending on the species. He reports that Bj has a single strand for the outer two bundles, and two separate strands for the inner bundle, and represents this as a "1-2-1" architecture. He reports that Btk is quite different, with each bundle containing three strands, a "3-3-3" architecture.
Wayne followed the Niehaus prescription for staining the lobes, and verified:
- the Monterey County plants indeed had a 1-1-1 architecture, consistent with its Bj identification; and
- specimens from San Marcos, previously classified as "Bj", had the 3-3-3 architecture of Btk.
See 4. Vascular Strands of Btk Compared With Bj for more details.
Summary of Differences Between True Bj and Southern California Plants
The following table gives 12 independent parameters for which we have found significant differences between the Monterey plants and the Southern California plants. For convenience, the table gives additional dependent parameters, such as the total perianth (= tube + lobes) and the median values for perianth length measurements.
| Characteristic | Bj | Southern California plants |
|---|---|---|
| Ovary color | purple | green |
| Width of anther axis tissue | << anther sacs | >~ anther sacs |
| Shape of top of anther axis tissue | V-shaped | gen W-shaped, toothed for coastal plants*; gen U-shaped for montane plants |
| Shape of top of anther sacs | elongate, hooded | rounded, planar |
| Architecture of vascular bundles in inner perianth lobes | 1-1-1 | 3-3-3 |
| perianth tube | 5.0-9.0 mm | 7.0-12.0 mm |
| median perianth tube | 7.0 mm | 8.0-10.8 mm |
| perianth lobes | 8.3-14.5 mm | 10-24 mm |
| median perianth lobes | 11.5 mm | 13.5-16.5 mm |
| perianth | 14.5-23.0 mm | 19-36 mm |
| median perianth | 18.4 mm | 22-27 mm |
| staminodes | 4.3-5.2 mm | 6.2-6.9 mm (needs additional measurements and plot) |
| filament | 1.2-1.5 mm | 1.0-3.5 mm |
| anther | 3.2-4.1 mm | 4.0-5.9 mm |
| ovary | 4.5-6.0 mm | 4.4-9.0 mm |
| style | 4.5-5.5 mm | 5.5-10.5 mm |
The discrimination in perianth length is so good that usually measurements of just a few flowers will immediately reveal which population the flowers are from. Median measurements of ten or more flowers always give good separation.
In addition to the differences in the table above which come entirely from our own measurements, the chromosome number is apparently different in the Southern California plants from that of Bj. As detailed above, our measurements of the San Marcos plants is consistent with them being an octoploid with a gametophyte number of 24, and inconsistent with the haploid and triploid gametophyte numbers of 6 and 18 reported by Niehaus.
Finally, we have measured the number of veins in the outer bract subtending the inflorescence in a few bracts from the Monterey County plants and from the San Marcos and Santa Rosa Plateau plants. We find 10 veins for the Monterey County plants, consistent with the 9-10 reported by Niehaus for Bj, and 6-7 veins for San Marcos and Santa Rosa Plateau plants, consistent with the 5-8 veins reported by Niehaus for Btk.
Note on the ovary color: we confirmed that Niehaus was right about the difference in ovary color. The fresh ovaries of the Monterey County population were all distinctly purple, something never seen in any Southern California plant despite intensive searching over two years by us for any specimen with a purple ovary. The fresh ovaries of all Southern California plants are unquestionably green.
We note that a small percentage (much less than 10%) of the Southern California plants do have purplish streaks on a small percentage of their surface. We have seen similar purplish streaks in B. elegans as well, and attribute no significance to this.
VII. Conclusions
- When examined in detail, no "Bj", or any other, specimens in Southern California remotely resemble plants classified as Bj from Monterey County, growing near the type specimen for Bj. There are at least twelve significant differences between the two sets of plants, many of them quite obvious, definitively ruling out these plants being assigned to the same taxon.
- The Niehaus (1971) paper has internal inconsistencies regarding the Southern California plants he classifies as "Bj" and "Btk", including a key that does not properly key out any of the specimens he assigns to Bj and Btk from Southern California, and descriptions that don't fit the Southern California plants. In particular, the ovaries of Southern California plants he classifies as "Bj" are all green, not purple, and the anther axis tissue is generally toothed, not entire.
- A possible explanation for these problems is historical, with the Southern California populations classified as "Bj" on the basis of the filament length alone, without corroboration by the many other characteristics of true Bj. Faced with the mammoth task of producing a manuscript giving many characteristics for the entire Brodiaea genus, Niehaus may simply not have gone back one last time to verify that the Southern California plants were correctly determined.
- Munz separated the Southern California plants into two populations, one he called "Bj" and one called "Btk", but those populations are inconsistent with the properties for those taxa as given by Niehaus.
- Munz may have been correct that there are two such taxa in Southern California, but the name "Bj" cannot be used for any of them. It is also possible that the Munz distinctions are not worthy of taxonomic separation, and there is only one taxon in Southern California.
Authors' note: this paper is nearly in final form, with just a few loose ends to track down and with a few additional measurements needing to be made to make the plots more complete. None of those is likely to change any of the main conclusions, but some modification may be necessary in details. In particular, Barry Prigge has brought to our attention a voucher from the Santa Monica Mountains with short perianth lengths, much shorter than the samples we collected there in 2004. It is therefore possible that a population of true "B. jolonensis" might be found as far south as the Santa Monica Mountains, or, alternatively, some populations of B. terrestris ssp. kernensis simply have shorter perianth lengths.
Acknowledgments
We gratefully acknowledge the help of Michael Charters, in locating specimens in the Santa Monica Mountains for us to analyze; James Lightner, for locating specimens in the Laguna Mountains; and especially Vernon Yadon for locating the specimens of the true Bj in Monterey County which are key to this analysis.
References
- The Jepson Manual: Higher Plants of California, 1993, Hickman, ed.
- Hoover, R.F. 1939, A revision of the genus Brodiaea, Am. Midl. Nat. 22:551-574.
- Hoover, R.F. 1939a, A definition of the genus Brodiaea, Bull. Torrey Bot. Club 66:161-166.
- Munz, P.A. 1974, A Flora of Southern California.
- Niehaus, T. F. 1971, A biosystematic study of the genus Brodiaea (Amaryllidaceae), Univ. Calif. Publ. Bot. 60:1-66.