A NEW ENDEMIC SPECIES OF LOMATIUM DESCRIBED FROM NORTH-EASTERN OREGON

From: Darrach, M.E. & D.H. Wagner. 2012. Lomatium pastoralis (Apiaceae), a new narrow endemic from Northeastern Oregon. Journal of the Botanical Research Institute of Texas 5: 427-435.

A new species, Lomatium pastorale D.H.Wagner ex M.E. Darrach & D.H. Wagner, is a tap-rooted, narrow endemic growing in shallow soils over basalt bedrock on the Umatilla and Wallowa-Whitman national forests in Umatilla County of northeastern Oregon, U.S.A. The species is most easily distinguished from other members of the genus by leaf morphology, inflorescence presentation, fruit shape, and pedicel length. The two recently studied populations are confined to small areas over a several km2 area. Populations can manifest as densely clustered plants in early seral settings wherein the species tends to be ecologically dominant, or as widely scattered plants in later seral stages. The species appears to require periodic disturbances in order to persist. Examination of annual root crown scars indicates that individuals may live in excess of 60 years. These data provide a critical element in the evaluation of population dynamics and informing conservation and management decisions and is apparently of significant conservation concern.

Original collections were made by David Wagner of an unrecognized Lomatium species in June 1978, from shallow lithosol soils at 1555 m on a gentle south-facing slope on the north side of Green Mountain in Umatilla County, Oregon on the Umatilla national forest. Subsequent examination of specimens by Lincoln Constance at the Jepson Herbarium, University of California at Berkeley, confirmed the material to be an undescribed entity. It was provisionally named Lomatium pastorale by Wagner recalling the prior history of the general area as an important domestic sheep pasturing summer range. In the intervening years this species has been purportedly recognized at several other nearby sites, but these locales remain to be revisited and confirmed regarding their present status. Lomatium pastorale has been found at several localities in the same general area as the recently studied populations; these should be revisited for reevaluation of size and vigor. Initial thoughts that the species was most probably not of immediate conservation concern owing to the robust nature of the type locality population and its apparent ability to proliferate in artificially disturbed sites contributed to a delayed publication schedule. Numerous subsequent botanical survey results of the general area by several experienced field botanists on both the Umatilla and Wallowa-Whitman national forests over the last three decades now argues strongly that the species is indeed both rare and in significant need of management as a conservation interest.

The species with which Lomatium pastorale is most likely to be confused are Lomatium leptocarpum Torr. & A. Gray and Lomatium ambiguum (Nutt.) Coult. & Rose. Lomatium leptocarpum is an occasional to frequent associate. It differs in having nearly sessile, narrowly oblong fruits, a usually well-developed radial involucel, narrow and more numerous leaflets, and peduncles which are only rarely strongly decumbent at the base. Lomatium ambiguum is infrequently found scattered within the known L. pastorale populations but it is more abundant on directly adjacent scabland lithosol sites with better drainage and similar gentle, but somewhat steeper slopes. Lomatium ambiguum has long pedicels with upright fruits, lacks an involucel entirely, typically includes at least one cauline leaf on mature specimens, and does not possess decumbent peduncle bases.

["Lomatium pastoralis" was published with an improper Latin termination and according to the International Code of Botanical Nomenclature Art. 32.7 had to be changed to "Lomatium pastorale".]

BOOK REVIEW: PLANTS ON OCEANIC ISLANDS: ORIGINS AND EVOLUTION

Bramwell, David, and Juli Caujape-Castells [editors] 2011. The biology of island floras. Cambridge University Press, New York. xv + 522 p. ISBN: 978-0-521-11808-8 Price: $120.00.

In 1999 I wrote about the plants of small, inshore islands in Barkley Sound, Vancouver Island (BEN 220-222; see also Cody [2006] Plants on Islands, Univ. Calif. Press, Berkeley, CA). There, with isolation distances of a few kilometers or less and with many island areas comparable in size to suburban gardens, endemics are non-existent; they are precluded by several factors:

i. continuous and high colonization rates from mainland sources;
ii. short residence times and high extinction rates of successful immigrants, and
iii. the relative brief period of several thousand years since sea levels were lower and the islands were contiguous with an expanded Vancouver Island "mainland."

In contrast, oceanic islands might enjoy millions of years of isolation with extremely infrequent colonization events, resulting in quite different floristic combinations from mainland sources. And if the islands are large (with equitable maritime climates), populations may persist long enough to diverge from mainland ancestors and become neo-endemics. Indeed, large-island plant populations may survive long enough to outlive those erstwhile ancestors and become paleo-endemics, especially where changing environments and vigorous evolution may have relegated their mainland relatives to obsolescence and extinction.

A new book from Cambridge University Press compiles chapters on the patterns of origin and evolution on many of the world's classical oceanic island refuges for plant relicts, for bizarre novelties, and adaptive radiations (n.b. another version of this review was published by Ecology in 2012). Twenty-one chapters by four dozen contributors present recent insights and advances in studies of island plants, given both new fieldwork and new tools-molecular systematics in particular. Around two-thirds of the contributors, editors included, are affiliated with botanical gardens or institutes, and are concerned largely with the endemic plants of islands.

There are at least 50,000 of these, found prevalently on isolated, deep-water islands-the older and larger, the more endemics-and including such flagship destinations for the inquisitive botanist as New Caledonia, New Zealand, Madagascar, and the Greater Antilles, the Galapagos, Canary and Juan Fernandez Islands, the Hawaiian, Pitcairn and Socotra Archipelagoes. These names still conjure up the magic and mystery of the great voyages of scientific discovery beginning around two centuries ago; they include some of the planet's most remote landmasses, where evolution has wrought some of its strangest (and most spectacular) achievements, and all are featured in this excellent compendium.

The scope of this research was established decades ago in a series of wonderful books by Sherwin Carlquist (1965: Island life, Natural History Press, New York; 1970: Hawaii: a natural history, Natural History Press, New York; and 1974: Island biology, Columbia University Press, New York). He described a multifaceted "island syndrome" of characteristics: increased longevity; decreased dispersal ability; herbaceous weeds to woody trees; small dull-colored and open corollas; and of course adaptive radiations. On new islands arisen over submarine faults or plate hotspots and colonized by long-distance dispersal, the ancestry of novel neo-endemics may be extremely difficult to determine, while on rifting islands with ancient continental connections, relicts or paleo-endemics, long extinct on the mainland, may persist to illuminate the waning of the gymnosperms and blooming of the angiosperms some 60 MA past. Such ancestry and relatedness questions were difficult or impossible for Carlquist in the 1960s and 1970s, as they involved e.g. measuring divergence times of endemics and mainland ancestors, identifying asynchronous double invasions of the same taxon, or classifying cryptic species within a complex radiation. But armed with current molecular techniques these challenges are both tractable and practical, and numerous applications along those lines are given in this book.

A few chapters in the book take a rather narrow focus, such as Chapter 13, which analyses the relationships among Limonium (fam. Plumbaginaceae) species between the Mediterranean basin and Macaronesia (Azores, Madeira, Canaries, Cape Verde Islands), based on a new molecular phylogeny. Chapter 7 has a similar approach to palms on Madagascar, where the group is spectacularly speciose (a dozen endemic genera and three times the species numbers found in Africa), and where a single genus (Dypsis: 161 endemic species) covers a great range of growth forms, sizes, and habits, from tiny shrubs to huge trees and lianas. The latter species have grapnel-like reflexed terminal leaves, and have an obvious and common neotropical forest counterpart in Desmoncus; but whereas this latter is ferociously spiny, Madagascar species are unarmed, perhaps because of herbivore paucity on the island.

The most intriguing chapters are, in my opinion, those that take the broadest view of the island colonization process, estimate the dates and sources of the successes, and the course of their subsequent adaptation and radiation. Exemplary is Chapter 4 on the Hawaii Islands. The unique isolation of Hawaii depends on a mid-Pacific location nearly equidistant from North America, eastern Asia, Australia, and Malesia (Malayan peninsular and the Philippines through the East Indies to New Guinea), and not much farther from South America. The Hawaiian flora of >1000 vascular species is 90% endemic, and derived from definitively long-shot colonization events from all of these sources via diverse mechanisms: zoochory in bird guts, anemochory with parachuted achenes or dust-sized spores (there are 162 endemic pteridophyte species), and floating diaspores on the ocean. The picture is enriched by the existence of widely spaced but numerous stepping-stones across Polynesia and Melanesia, by the well-known geological history of Hawaii as an island chain with links rising then falling with plate progression WNW over a thin-crust hotspot, by incoming seed- and fruit-eating migrant waders sheltering from Alaskan winters, and by the dated process of human colonization of Hawaii, along with numerous commensals, animal and vegetable. Despite our accumulating broad understanding, fascinating questions remain, such as how the nine endemic Scaevola (Goodeniaceae) species were derived from three separate colonization events, one from Australia, the family's heartland, and two from pan-tropical ancestors with America ties; and how the nineteen endemic and genetically identical species of Bidens (Asteraceae) on Hawaii came to develop more morphological diversity than did their 300 congeners on five continents put together? Since many Hawaiian endemics have divergence times from known ancestors that are older than the islands (e.g., > 10 MA, the age of venerable Kauai), we have the delightful image of ancient and established plant taxa on paleo-Hawaiian islands back-hopping from older WNW islands as they submerge below sea-level onto newly emergent islands to the ESE. That sort of process presumably helps account for how one of the deepest divergences, that of the endemic genus Hesperomannia (Asteraceae; 20-17 MA), remains extant with species on three much younger Hawaiian islands, although it doesn't help with understanding why this taxon's nearest relatives are in Africa!

Similar insights emerge from other chapters with wide pan-floral approaches, including Chapter 5 on the Galapagos Islands, a plate boundary archipelago on the equator with largely South American sources, and Chapter 9 on New Caledonia, a large, relictual chunk of the old continent of Zealandia, lying on the Tropic of Capricorn, east of Australia and northwest of New Zealand. These three (with Hawaii) Pacific Basin locations make for some nice contrasts and comparisons, with respect to ancient and modern sources of colonists, and the closest extant relatives of the island plants. In the Galapagos, for example, and notwithstanding that the closest relatives of nine out of ten island plants have Andean distributions, including those of the endemic Scaevola and Opuntia species, there are surprisingly strong relationships between the Galapagos and Caribbean floras. This link is exemplified by the Caribbean ancestry of several infra-specifically endemic Darwiniothamnus spp., and is rendered more plausible by the circum-tropical ocean currents that ran east to west through the open Tropical American Seaway, until its closing by the Panamanian isthmus ca. 3.5 MA. Tropical America contributions have produced the endemic Alternanthera, while the endemic cotton Gossypium darwinii derives from a Baja Californian ancestor.

Age, isolation, and total land area all decline from Hawaii to the Galapagos, and so accordingly does the endemicity (in both level and taxon numbers; see Table 1 http://bomi.ou.edu/ben/457/table.png). Note that all three sites in Table 1 span a similar habitat gradient, from dry, lowland scrub and woodland to higher-elevation humid forest, although in Hawaii the high tops reach into the alpine zone. In New Caledonia, ca. 90% of the land mass is one large island (Grand Terre), which is about the size of all the Hawaiian Islands combined. Its present level of isolation, nearly equidistant from Australia and New Zealand, is intermediate between the Galapagos and Hawaii, but its isolation over time is very much greater, 50-60 MA (although it has been partly submerged at intervals during that time period). In terms of endemics, this is the place to see them-species, genera, and even families found nowhere else! New Caledonia's flora re-emphasizes the distinction between paleo-endemics, whose relatives were once widespread but which now survive only on the island, and neo-endemics, the sort derived from long-distance colonization and the sort that characterize both the Hawaiian and Galapagos archipelagoes, that have never had land connections with other land masses. Paleo-endemics abound on New Caledonia, especially ancient gymnosperms such as Araucariaceae and Podocarpaceae and relicts in classical Gondwanan families such as Proteaceae and Myrtaceae. To see the only parasitic gymnosperm, Parasitaxus, a shrub grafted to the roots of other podocarps via intermediary mycorrhizae, or the sole member of the Amborellaceae, a family basal to the angiosperms, this is your destination.

The last five chapters in the book have a conservation focus, particularly appropriate since an estimated 20,000 of the 50,000 island endemics are considered threatened or endangered. They address oft-cited threats such as climate change, invasive alien plants, and anthropogenic habitat degradation, among others. All, of course, have a major potential to accelerate the rate of island extinctions. But, curiously, not one mention is made of a balanced but dynamic equilibrium between colonization and extinction that leads to a natural species turnover and to ongoing extinction as a way of island life (or death). One threat that appears especially ominous is climate change, since the option to track such change by migrating across the map is hardly realistic on islands. But contributors here rank other threats ahead of climate change, especially invasive aliens and human impacts. It would be a rare island indeed that is free of the effects of human interference, although, surprisingly, in one case this may have been overestimated. Madagascar has an amazing flora approaching 14,000 species, >90% endemic (Chapter 17). Most of this diversity resides in the wet, eastern forests; presently the island is three-quarters grassland, thought to be a result of forest clearance by humans who settled there 1800 years ago. But a recent study (Bond, William J., John A. Silander, Jr., Jeannin Ranaivonasy, and Joelisoa Ratsirarson. 2008. The antiquity of Madagarcar's grasslands and the rise of C4 grassy biomes. Journal of Biogeography 35:1743-1758) pointed out that these grasslands are most unlikely to be recent, as they are composed of 88 C4 grass genera (around 5/6 of the diversity of southern African grasslands), and six of them endemic. This minor positive note notwithstanding, odds for the preservation of island floras in the face of imminent and varied threats remain slim. From botanists and botanical gardens to governments and a multitude of acronymic NGOs, our political, socio-economic, and scientific entities will need to construct a wide range of treaties and trade-offs before island conservation goals seem remotely possible.

BOOK ANNOUNCEMENT: NEW BOOK ON BRYOPHYTE FLORA OF QUEBEC

Faubert, Jean. 2012. Flore des bryophytes du Québec- Labrador. Volume 1 : Anthocérotes et hépatiques. Société québécoise de bryologie, Saint-Valérien, Québec, xvii + 356 p., illus. [hard cover] ISBN 978-2-9813260-0-3v Price: CND$80.00 + postage and handling For excerpts see: http://www.societequebecoisedebryologie.org/documents/Apercu_Flore_bryophytes_Quebec.pdf To order: www.societequebecoisedebryologie.org

Flore des bryophytes du Québec-Labrador intends to survey, describe, and provide identification means to all mosses, liverworts and hornworts known to occur naturally in Quebec and Labrador. Identification keys to genera, species and infraspecific taxa are provided, and the following information is presented for each taxon: a short description with diagnostic characters, habitat and ecological preferences, a distribution map for Quebec and Labrador, additional comments, drawings pointing out characters useful or necessary for identification, and references to other relevant publications.

Many species which are likely to occur in Quebec and/or Labrador but have not yet been collected there are discussed or described. The book also includes photographs showing the general habit of each genus, artistic drawings depicting each family, an illustrated glossary, a bibliography, and an appendix proposing French and English names.

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