''Sedum lanceolatum'' is a species of flowering plant in the family

Crassulaceae The Crassulaceae (from Latin ''crassus'', thick), also known as the stonecrop family or the orpine family, are a diverse family of dicotyledon flowering plants characterized by succulent leaves and a unique form of photosynthesis, known as Cr ...

known by the common names spearleaf stonecrop and lanceleaf stonecrop. It is native to western North America and occurs in western Canada and the United States. It is distributed from

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a U.S. state, state in the Southwestern United States. It is the list of U.S. states and territories by area, 6th largest and the list of U.S. states and territories by population, 14 ...

and

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe, New Mexico, Santa Fe , LargestCity = Albuquerque, New Mexico, Albuquerque , LargestMetro = Albuquerque metropolitan area, Tiguex , Offi ...

and as far east as

South Dakota South Dakota (; Sioux language, Sioux: , ) is a U.S. state in the West North Central states, North Central region of the United States. It is also part of the Great Plains. South Dakota is named after the Lakota people, Lakota and Dakota peo ...

and

Nebraska Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the so ...

. It grows in exposed, rocky mountainous habitat at moderate and high elevations, up to 4048 meters in the

Rocky Mountains The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch in straight-line distance from the northernmost part of western Canada, to New Mexico in ...

.DeChaine, E. G. and A. P. Martin. (2005)
Marked genetic divergence among sky island populations of ''Sedum lanceolatum'' (Crassulaceae) in the Rocky Mountains.
''

American Journal of Botany The ''American Journal of Botany'' is a monthly peer-reviewed scientific journal which covers all aspects of plant biology. It has been published by the Botanical Society of America since 1914. The journal has an impact factor of 3.038, as of 201 ...

'' 92:477-486. The plant persisted and evolved on

sky island Sky islands are isolated mountains surrounded by radically different lowland environments. The term originally referred to those found on the Mexican Plateau, and has extended to similarly isolated high-elevation forests. The isolation has ...

s and nunataks in these ranges during glaciation events during the

Pleistocene epoch The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

. This is a

succulent plant In botany, succulent plants, also known as succulents, are plants with parts that are thickened, fleshy, and engorged, usually to retain water in arid climates or soil conditions. The word ''succulent'' comes from the Latin word ''sucus'', meani ...

forming basal rosettes of knobby or pointed leaves up to 3 centimeters long. Smaller leaves occur farther up the stem and often fall away by the time the plant blooms. The stems are about tall. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed ...

is made up of one or more erect arrays of several flowers. The flowers have yellow petals sometimes tinged with red, each lance-shaped petal just under a centimeter long. The

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filam ...

s are tipped with yellow anthers. The plant reproduces sexually by its tiny, lightweight seeds, or

vegetatively Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is any form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or spec ...

when sections of its stem break off and root.

Ecology

''Sedum lanceolatum'' is the host plant of the butterfly species ''

Parnassius smintheus ''Parnassius smintheus'', the Rocky Mountain parnassianJim P. Brock and K. Kaufman. Kaufman Field Guide to Butterflies of North America, New York, NY:Houghton Mifflin, 2003. or Rocky Mountain apollo, is a high-altitude butterfly found in the Rock ...

''. ''Sedum lanceolatum'' produces a deterrent cyanoglycoside, sarmentosin, so that herbivores do not feed on it. The larvae of ''Parnassius smintheus'' sequester sarmentosin from the plant for their own defense. However, it has been found that if the ''S. lanceolatum'' plant becomes physically damaged by mechanical means, the larvae feeding on it have reduced growth rates, possibly due to an induced defense by the plant itself. While damage by insects does not cause defense by ''Sedum lanceolatum'', damage from feeding by the larvae does induce defense by the plant. Consequently, the larvae often hurry to feed, then switch to another plant within the time window offering highest nutritional quality. Larvae will typically feed and leave a plant in less than half an hour. From November to February, the leaves of their foodplant are fatally toxic to the larvae, but for the rest of the year, the larvae feed and develop normally. If the snow melts before March, the eggs hatch while the larval foodplant is still

toxic Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a subs ...

, and the larvae perish.

References

External links

Jepson Manual TreatmentUSDA Plants ProfileWashington Burke MuseumPhoto gallery
{{Taxonbar, from=Q7445431 lanceolatum Flora of the Western United States Flora of the North-Central United States Flora of California Flora of Colorado Flora of the Sierra Nevada (United States) Flora of the Rocky Mountains Flora without expected TNC conservation status