| BEN |
| BOTANICAL ELECTRONIC NEWS |
|---|
| ISSN 1188-603X |
| No. 493 July 9, 2015 | aceska@telus.net | Victoria, B.C. |
|---|
From: P.M. Catling paul.catling@agr.gc.ca The following responds to questions from British Columbia botanists, regarding changes to Amelanchier alnifolia var. semiintegrifolia in the most recent taxonomic treatment of North American Amelanchier (Campbell et al. 2014). There are two considerations: Part 1 - Circumscription and Part 2 - Nomenclature.
A general pattern
Treatments of Amelanchier in British Columbia have generally followed Jones (1946) recognizing five taxa in two groups : Three of these have relatively short petals less than 12 mm long; (1) the widespread and often stoloniferous Amelanchier alnifolia var. alnifolia, (2) the uniquely entirely glabrous Amelanchier alnifolia var. pumila of higher elevation in the mountains, and (3) the dwarf Amelanchier alnifolia var. humptulipensis endemic to the southern Georgia Basin (most recently placed in synonymy with A. alnifolia var. alnifolia, see Catling 2013). The other two have larger petals over 12 mm long including (4) Amelanchier alnifolia var. semiintegrifolia (=_A. florida Lindley), the tall shrub or small tree resembling A. alnifolia var. alnifolia initially associated with the coast (in and west of the Cascades), - but actually much more widely distributed to the east and in the Rocky Mountains), and (5) the very distinctive deliquescent shrub or small tree with large flowers that occupies the dry interior valleys from southern British Columbia in the Rockies and east of the Cascades south to northern Utah.
A different concept
The key point here is that number 4, Amelanchier alnifolia var. semiintegrifolia, was accepted as a large-flowered relative of A. alnifolia and this was so in numerous treatments (e.g. Jones 1946, Hitchcock et al. 1961, Scoggan 1978, Pojar 1999, Catling 2012). However, Nielsen (1937) described A. florida as having relatively small flowers and in Campbell et al. (2014), the flowers of var. alnifolia and var. semiintegrifolia are considered to be roughly the same size: petals 9-14 mm long and sepals 2.6-3.6 mm long for var. alnifolia; and petals 9.9-13.9 mm long and sepals 2.2-3.2 mm long for var. semiintegrifolia. With the flowers being the same size, the question is: how are they distinguished by Campbell et al. (2014)? The answer is by the inflorescence and basal pedicels: inflorescence 26-43 mm long and basal pedicels 8-16 mm long for var. alnifolia; inflorescence 14-26 mm long and basal pedicels 3-8 mm long for var. semiintegrifolia. To simplify the situation, Campbell et al. (2014) have var. semiintegrifolia as a tall plant (a tree or a shrub) like other authors, but with relatively small flowers, shorter inflorescences, and short pedicels unlike other authors where the tall plant has large petals and long pedicels.
There are two reasons why the changed concept of Amelanchier semiintegrifolia appears not to represent a taxon on the landscape. Firstly a recent study (Catling 2013) on southwestern Vancouver Island found that the best character other than height for separating ecologically based taxa was petal length, the one used by all recent authors except Campbell et al. (2014). Secondly, this recent study found the characters with the highest (and highly significant) correlations with petal length were pedicel length and height. In general, larger taxa of Amelanchier have larger flowers.
History of a large-flowered taxon
Botanists circumscribed a large-flowered taxon and Hitchcock (in Hitchcock et al. 1961, p. 94). found a name for it at varietal level evidently based on the synonymy of Jones (1946) and on account of its close similarity to Amelanchier alnifolia. The tall, large-flowered Amelanchier with a hairy ovary which occurs in the Pacific Northwest was long called A. florida. Hitchcock (1961) reduced it to varietal rank using the first available varietal name, Amelanchier ovalis var. B semiintegrifolia Hooker (1832) which was indicated in the synonymy of Jones (1946, p. 73). Subsequent authors have accepted the taxon at this rank and name and its circumscription as briefly described above. Regardless of whether or not Hitchcock's choice of the name was a good one, i.e. whether or not it applied to the large-flowered plant as he intended with "petals well over 12 mm long", the name has long and widely been used in this sense of the large flowered plant and there is no need to change it. However, the following notes are of interest.
(1) Amelanchier florida was the large-flowered taxon Jones (1946) applied the name correctly, although he restricted it too much geographically. Hitchcock et al. (1961, p. 95) correctly noted that "the material from east of the Cascades is often arbitrarily referred to other taxa".
Lindley's Amelanchier florida had large flowers "with petals over ¾ inch long" (19 mm) (Lindley 1833) and "ovary summit woolly" (Nielsen 1937), and originated in "North-West America". Consequently, it could only be the plant generally recognized as A. florida or A. alnifolia var. semiintegrifolia sensu recent authors. Nielsen (1937) developed a broader circumscription based on examination of specimens from Williamette University in Oregon and the University of Washington. Here (Nielsen 1937) the petals were listed as 8-13(16) mm long. This was probably a result of Nielsen not understanding A. alnifolia and its occurrence on the coast, but in a more extensive study by Jones (1946), the petals of A. florida were described as 12-15 mm long.
Since Lindley noted the long petals they should be apparent in his type. The type in the Botany School at Cambridge, has two specimens on the sheet (described in Nielsen 1937), one on the left and one on the right. In the lower right is written "Amelanchier florida" in Lindley's hand (confirmed by Christine Bartram at Herb. Lindley) with a reference to the Bot. Reg. description. Lindley commonly placed two or more collections on a sheet, sometimes different collectors and locations on a single sheet and in these cases he usually wrote the name of one of the collectors/dates/locations at bottom left and labelled the other collections on the sheet closer to the actual specimen (Christine Bartram pers. comm.). Thus the writing in the lower right would likely refer to the right hand specimen while the writing in the lower left would likely refer to the left hand plant which is mounted on part of a sheet that was cut out and glued on. This lower left writing reads "N W America Douglas 1826". This also appears to be in Lindley's hand (confirmed by Christine Bartram). The left hand plant does have writing definitely associated with it and that is the writing between the branches: "N.W. Am. Douglas". Again this is in Lindley's hand (confirmed by Christine Bartram). Larger petals on this specimen are 16-19 mm long compared to larger petals 11-14 mm long in the right hand specimen. An important point here is that the report in Nielsen (1937) of petals 8-11 mm long in this type is not accurate. With the associated writing corresponding to "A native of North-west America" in Lindley's text accompanying plate 1589 and his specific reference to petals ¾ of an inch (19 mm) long, the left hand plant appears to be an appropriate choice of lectotype. A photo of a flower from this left hand plant (kindly provided by Christine Bartram) shows an ovary that is densely pubescent on the top. This latter observation eliminates the possibility of the left hand plant being A. cusickii Fernald which is either glabrous or with sparse hair on the top of the ovary.
(2) Amelanchier alnifolia var. semiintegrifolia Jones' placement of Amelanchier ovalis (Willdenow) Persoon var. B semiintegrifolia Hooker in synonymy under A. florida was apparently based on the fact that it was described from Fort Vancouver on the Columbia River and Jones thought that the only Amelanchier on that part the Pacific coast was his large-flowered (petals 12-15 mm long) A. florida (see his map, Jones 1946, Map 10, p. 75). Jones implemented this idea although he had A. alnifolia, a major food item transported by native people, mapped 30 km to the east (and A. alnifolia would almost certainly have been native to the region as a result of introduction along this major transport route, if not naturally occurring. Thus Amelanchier ovalis var. B semiintegrifolia may actually be a synonym of var. alnifolia (Aronia alnifolia Nuttall, 1818), especially with Hooker associating it with the putataive A. parviflora. Interestingly Hooker's semiintegrifolia was published in 1832 in part 4 of volume 1 of Flora boreali-americana, whereas A. florida was published a year later in 1833.
A specimen which is appropriately considered as Hooker's type of semiintegrifolia is at KEW ( http://specimens.kew.org/herbarium/K000758511 ) in Herbarium Hookerianum (1867). The left hand branch on the sheet is the one with the larger flowers and is associated with the text on a label which corresponds to Hooker's description: "Plentiful around Fort Vancouver and at the Grand Rapids and on the high ground of the Multomah River". The label also bears the name "A. parviflora" given by Hooker as a synonym. The flowers are 7-9 mm long so it is not the large-flowered plant. A specimen at HUH (00026127, also with relatively small petals) is apparently a Douglas collection that Hooker may have sent to Asa Gray. http://kiki.huh.harvard.edu/databases/specimen_search.php?fragmentid=129506
(3) Amelanchier florida var. parvifolia Amelanchier florida var. parvifolia Hort. ex Loudon (Arb. & Fruit Brit. 2: 877. 1838) applies to a dwarf shrub (perhaps corresponding to A. florida Lindley var. humptulipensis G.N. Jones) most recently placed in synonymy with A. alnifolia var. alnifolia (Catling 2013) and thus clearly not embracing the concept of the large-flowered plant.
(4) Amelanchier alnifolia var. florida The first available and most correctly applied name for this large-flowered plant at varietal rank appears to be Amelanchier alnifolia var. florida (Lindl.) Schneider, Illustr. Handb. Laubh. 1: 739. Fig. 411 (1906). Although Schneider may have accidentally confused the long sepals of florida with the short petals of A. alnifolia (perhaps with a mistake in scale of his illustration) his new combination is clearly defined through his reference to Lindley's publication of A. florida in Bot Reg.
The varieties of Amelanchier alnifolia can be separated using petal length as done by recent authors (e.g. Jones 1946, Hitchcock et al. 1961, Scoggan 1978, Pojar 1999, Catling 2012) except Campbell et al. (2014). The name A. alnifolia var. semiintegrifolia can be applied to the large-flowered, few-stemmed (or at least fastigiate) Amelanchier taxon with a hairy ovary. It appears that the first available name for the large flowered plant at varietal rank was Schneider's var. florida, but Hitchcock trusted the synonymy of Jones and applied semiintegrifolia (which should have been a synonym of var. alnifolia). Regardless there is no urgent need to replace the widely used and familiar name which until recently had a clear circumscription for botantists in the Pacific Northwest and will hopefully continue to be used in its historic sense.
Spribille, T., P. Resl, T. Ahti, S. Pérez-Ortega, T. Tønsberg, H. Mayerhofer and H. T. Lumbsch. 2014. Molecular systematics of the wood-inhabiting, lichen-forming genus Xylographa (Baeomycetales, Ostropomycetidae) with eight new species. Acta Universitatis Upsaliensis, Symbolae Botanicae Upsalienses 37(1): 1-87.
Throughout North America, but especially in the Pacific Northwest and western mountains, one frequently encounters decorticate logs and snags spotted or streaked with tiny brownish to black ascomata often with piles of brownish granules ranging into soredia. Although a few of these represent non-lichenized fungi (e.g., Agyrium rufum), most belong to the lichenized genus Xylographa, a genus notorious for its variability and taxonomic issues. Thanks to Toby Spribille and his collaborators, we now have a monograph of the genus covering the Northern Hemisphere and South America. The authors recognize 20 species including eight described as new in this work. There are very useable keys, full descriptions, excellent colour photographs, genetic analyses and phylogenetic trees to show species and generic relationships, and other features that might be expected in a full monographic treatment. The publication is part of the series, Symbolae Botanicae Upsalienses, long known for its high quality monographic treatments of plants and fungi, but especially lichens.
Editorial Note: There are eight species described here as new, among them Xylographa bjoerkii and X. schofieldii named after the prominent Pacific Northwest botanists, and X. lagoi, the new taxon named in memory of Manuel Lago 'Chiquito', a ranger for the forest service in the Muniellos Nature Reserve who was murdered by poachers in 1980 while working in the Reserve.
Kauffmann, Michael (Edward); Parker, (V. Thomas) Tom; Vasey, Michael (C.) (text) & Bisbee, Jeff (photos). May 2015. Field guide to manzanitas: California, North America, Mexico. Backcountry Press, Kneeland (http://www.backcountrypress.com/). 170 p., ISBN 9781941624029 [soft cover], Price US$27.95
In the October and December 2013 issues of Taxon (62: 1092, 1372-1373) I enthusiastically reviewed Michael Kauffmann's two guides to conifers of the Pacific Slope. When this talented field guide-meister asked me if I would like a review copy of his just published Field guide to manzanitas, I responded "absolutely, "fully knowing that the spectacular excellence of a Kauffmann guide would demand immediate treatment in the RevNot column. The book arrived in yesterday's post just as I was closing the June RevNot. I figure that a relatively brief review appearing in June is preferable to a longer, perhaps more critical review appearing in August. A longer review may yet materialize. Hope always springs eternal.
Arctostaphylos (manzanita) has one circumpolar species, A. uva-ursi (bearberry, kinnikinnik), with nine forms, including five in California, and subsp. cratericola "found on top of several high-elevation volcanoes in Guatemala, thousands of miles from the closest A. uva-ursi in New Mexico, and nowhere in between"(p. 192); "this is the only taxon not treated herein" (p. 10). Most (98) of the 105 species and subspecies of manzanita are native to the California Floristic Province in a variety of habitats, including coastal bluffs and montane forests plus the stereotypical chaparral. There are 62 narrow endemics; 49 are coastal (p. 10). Arctostaphylos occurs in 54 of the 58 counties of California, with at least 20 taxa in Monterey County; four counties in the Central Valley (Kings, Merced, Sacramento, and San Joaquin Counties) lack manzanitas. Many famous taxonomists have worked on Arctostaphylos, which despite their collective efforts, has often been regarded as one of those groups easy to identify to genus, but hard to species.
Field guide to manzanitas might well demolish that notion, not only because of its many identificatory aids and spectacular color photos, maps, and graphics, but also because of the all-star cast generating and interpreting them: Kauffmann, Parker & Vasey for text, with Bisbee for most photos. After all, it was Parker, Vasey & Jon E. Keeley who treated Arctostaphylos in both the print The Jepson Manual (2012; Philip V. Wells did the genus in the 1993 edition) and the online Jepson eFlora (2013-).
Field guide to manzanitas has five sections: Section 1: A 14-page"discussion" includes a 1-page preface, a 1-page quick guide, a 12-page, 4-part "introduction" to Arctostaphylos treating: the California Floristic Province (CFP); origin, ecology, and diversification; conservation; and "beyond" the CFP. Section 2: The 20 pages titled "regional keys to species and subspecies" characterizes the genus (5 pages) and then gives keys to 7 regions: Klamath Mountain[s]; San Francisco Bay area; coastal CenCal; Sierra Nevada; SoCal; Baja California; and outside the CFP. Section 3: The 98-page descriptive part treats 67 species and 53 subspecies (104 taxa) of manzanita that are alphabetically arranged. Each taxon has a distribution map, several superb color photos, and synoptic description for, as relevant, "form," "stem," "leaves," "flowers," "fruit," "habitat," "observations," "identification,"and "remarks." Section 4: The 16-page fourth section ("destinations") describes 4 sites for each of the 7 regions: northwestern NoCal; central Sierra Nevada; San Francisco Bay area; Monterey Bay area; coastal CenCal; SoCal; and Baja California. Section 5: Other than the lists of taxa of Arctostaphylos by region (58 counties of Alta California; Baja California; outside California), the back matter is fairly standard (a 2-page unillustrated glossary, a 2-page bibliography, bionotes, but no index). The website (http://www.backcountrypress.com ) highlights the main features of this grand synthesis. A superb guide for all manzanita lovers
Subscriptions: http://victoria.tc.ca/mailman/listinfo/ben-l.
Send submissions to aceska@telus.net
BEN is archived at http://www.ou.edu/cas/botany-micro/ben/