Dudleya virens subsp. extima

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Dudleya virens subsp. extima
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Saxifragales
Family: Crassulaceae
Genus: Dudleya
Species:
Subspecies:
D. v. subsp. extima
Trinomial name
Dudleya virens subsp. extima
Moran (1995)
Synonyms [1]
  • Stylophyllum virens subsp. extima Moran

Dudleya virens subsp. extima is a subspecies of succulent plant in the family Crassulaceae commonly known as the Guadalupe green liveforever. [2] It is a rosette-forming leaf succulent, with both green and white waxy foliage. It has white flowers with spreading petals that bloom from May to June. It is a somewhat small plant, continuing a southward trend of decreasing size relative to other Dudleya virens subspecies. This plant is endemic to Guadalupe Island in the eastern Pacific Ocean, which is 241 kilometers off of the Baja California coast. It is very rare, with this plant only surviving on sheer cliff faces and canyons, out of the reach of the former feral goat population rampant on the island. [3] It closely resembles a miniature version of Dudleya virens subsp. virens, [4] but it may be more nearly related to the local Dudleya guadalupensis . [5]

Contents

Description

Like most other Dudleya, it grows rosettes with succulent leaves on the tips of stems (which are variably referred to as a caudex). The caudex is 1 to 2.5 cm thick, either branching into clumps of up to 15 rosettes or elongating up to 30 cm. The rosettes are 5 to 15 cm wide, containing 15 to 55 crowded leaves. [4]

The leaves are bright green or covered with white epicuticular wax (known as a farina). The leaf shape is linear to oblong-oblanceolate. The dimensions of the leaf range from 4 to 7 or rarely up to 17 cm long, 6 to 10 mm wide above when linear-shaped, but up to 15 mm wide above when oblanceolate, 8 to 15 mm wide at the base, and 2 to 4 mm thick. [4]

The peduncle 5 to 20 cm tall, 2 to 5 mm thick, and often rather weak. The peduncle is bare of bracts in the lower 2 to 7 cm, but it has 12 to 35 ascending bracts above, which are shaped triangular to lanceolate. The inflorescence is 2 to 7 cm wide, composed of 2 to 4 ascending branches. The cincinni (terminal branches) bear 3 to 10 flowers, which are suspended on pedicels 1 to 6 mm long. Flowers are white with petals 7 to 10 mm long. [4]

Taxonomy

Taxonomic history

In 1892, Dr. Francescho Franceschi, a horticulturist from Santa Barbara, visited Guadalupe Island. He published an account of the trip and the plants he found, and among them, he reported a " Cotyledon sp." on a rock by a trail not far from the landing. No other expeditions found or mentioned Dudleya until 1948, when Reid Moran and George Lindsay visited the island. The island had been decimated by feral goats that had been introduced by European sailors, which caused significant damage to the flora and left many plants only extant in areas where the goats could not reach. On the far northern portion of the island, where the Guadalupe pine grows, Moran and Lindsay found a clump of Dudleya growing on a north-facing cliff around 3,500 ft (1,100 m) above the sea, out of reach of the goats. Moran noted this plant's similarity to the Dudleya caespitosa found on the Californian coast. [6]

Moran and Lindsay continued returning to the island, eventually gathering more information on the Dudleya species that occurred on the northern cliffs and canyons. The first plant Moran noticed in 1948 was on what he called Hemizonia Cliff, and he later found more examples similar to it. The plants on Hemizonia Cliff have oblong to oblanceolate leaves covered in a white farina, and clustered, subsessile rosettes. Initially, the first plant collected on Hemizonia Cliff was a tetraploid, so Moran placed it with Dudleya virens subsp. hassei. Green, diploid plants with narrower and sharply acute leaves were discovered in the cliffs and canyons farther south, which Moran thought might make it feasible to distinguish these two taxa on the island. However, the second plant collected on Hemizonia Cliff turned out to be a diploid as well, so Moran kept all the plants under one subspecies, published and described in 1995. [3] [4]

Etymology

The subspecies name extima, means remote, with this subspecies of Dudleya virens growing the furthest from the North American continent. The true furthest out of the Dudleya is the closely related and nearby Dudleya guadalupensis , which occurs at the farther end of the island. [4]

Phylogeny

Phylogenetic analyses have placed this plant as a probable sister taxon to Dudleya guadalupensis, which occurs on the southern end of Guadalupe Island and its islets. [5]

Distribution and habitat

It is endemic to Guadalupe Island, [2] a volcanic island in the eastern Pacific Ocean belonging to Mexico. It is not on the continental shelf of North America, and is over 241 kilometers from the coast of Baja California. Plants are only found on the north and northeast half of the island, on steep, north-facing cliffs and canyons, and under rocks in the forest of Quercus tomentella . It is found in what Reid Moran called Hemizonia Cliff at 800 m (2,600 ft), the oak forest at 700 m (2,300 ft), Barracks Canyon at 450 to 420 m (1,480 to 1,380 ft), and Esparsa Canyon at 250 m (820 ft). It is scarce, but out of reach of the former goats, the plant appears to be surviving. [3]

Related Research Articles

<i>Dudleya virens</i> Species of succulent

Dudleya virens, the green liveforever or bright green dudleya, is an uncommon species of perennial, succulent plant in the family Crassulaceae, native to several coastal southern California and Baja California locations.

<i>Dudleya</i> North American succulent genus

Dudleya, commonly known as liveforevers is a genus of rosette-forming succulent plants in the stonecrop family, Crassulaceae, consisting of about 68 taxa in southwestern North America and Guadalupe Island. The species come in many forms, with some large and evergreen, others geophytic and deciduous. Yet, despite their dramatic variations in appearance, most species readily hybridize. The flowers of Dudleya have parts numbered in fives, with the petals arranged in tubular, star-shaped, and bell-shaped forms and, when fruiting, are filled with tiny, ovoid-crescent-shaped seeds.

<i>Dudleya abramsii <span style="font-style:normal;">subsp.</span> setchellii</i> Species of succulent

Dudleya abramsiisubsp. setchellii, known by common name as the Santa Clara Valley dudleya or Santa Clara Valley liveforever, is a member of the Dudleya genus of succulent perennials, members of the family Crassulaceae. The Santa Clara Valley dudleya, endemic to the Santa Clara Valley region in the southern San Francisco Bay Area, was listed on 3 February 1995, as an endangered species. It is considered to be a subspecies of Dudleya abramsii, but its taxonomic status is still unclear. Its closest relative is Dudleya cymosa subsp. paniculata, which is a morphologically similar sister taxon.

<i>Dudleya traskiae</i> Species of succulent

Dudleya traskiae is a rare succulent plant known by the common name Santa Barbara Island liveforever. This Dudleya is endemic to Santa Barbara Island, one of the Channel Islands of California, where it grows on rocky bluffs. The plant has a basal rosette of flat, spade-shaped fleshy leaves up to 15 centimeters long, which are pale green to yellowish. It erects tall stems bearing dense, rounded inflorescences of many bright yellow flowers.

<i>Dudleya greenei</i> Species of succulent

Dudleya greenei is a perennial species of succulent plant known by the common names Greene's liveforever, or Greene's dudleya. It is endemic to the Channel Islands of California, where it grows along the cliffs of four of the eight islands. It is a highly variable plant, presenting with multiple forms and varying levels of ploidy. Taxonomically, this species is an insular segregate of Dudleya caespitosa, and was placed as a stopgap taxon by Reid Moran in his 1951 thesis on the genus. It is characterized by white or green leaf rosettes, loomed over by inflorescences bearing pale yellow to white flowers. It is a member of the subgenus Dudleya, as it cannot be propagated from leaf cuttings, does not grow from a corm, and has tight petals.

<i>Dudleya attenuata</i> Species of succulent

Dudleya attenuata is a species of perennial succulent plant known by the common name taper-tip liveforever, native to Baja California and a small portion of California. A rosette-forming leaf succulent, it has narrow pencil shaped leaves that can often be found covered in a white epicuticular wax. The thin, sprawling stems branch to form the clusters of rosettes, with plants creating a "clump" up to 40 cm wide. The small flowers are white or yellow, with 5 spreading petals. It is a diverse, variable species that extends from the southernmost coast of San Diego County to an area slightly north of the Vizcaino Desert, hybridizing with many other species of Dudleya in its range. Some plants with white or pinkish flowers were referred to as Orcutt's liveforever, referring to a former subspecies split on the basis of the flower color.

<i>Dudleya guadalupensis</i>

Dudleya guadalupensis is a very rare species of succulent perennial plant in the family Crassulaceae commonly known as the Guadalupe liveforever. It is a rosette-forming leaf succulent, with foliage that is variously colored light green, green, and a waxy white. It is characterized by dense leaves that fold over the center in dormancy, a curving, sinuous flower stalk, and white, cup-shaped flowers. It is endemic to the rocks and islets off of Guadalupe Island, an isolated volcanic island in the Pacific Ocean located 241 kilometers off of the coast of Baja California.

<i>Dudleya rigida</i> Species of flowering plant in the family Crassulaceae

Dudleya rigida is a species of succulent perennial plant in the family Crassulaceae known commonly as the La Laguna liveforever. Characterized by a tall inflorescence with pendant yellowish-red flowers, it is a very rare plant whose existence was doubtful until botanist Reid Moran accidentally re-discovered it. It is endemic to the Sierra de la Laguna in Baja California Sur, Mexico.

<i>Dudleya pauciflora</i> Species of succulent

Dudleya pauciflora is a species of succulent plant in the stonecrop family known by the common name few-flower liveforever. It is characterized by its small crowded rosettes of narrow leaves and its colorful inflorescence with red-yellow flowers. Found growing on rocky outcrops and cliffs in the high elevation mountains of the Sierra de San Pedro Martir and the Sierra de San Borja, it is endemic to the state of Baja California, Mexico.

<i>Dudleya campanulata</i> Succulent plant native to Baja California, Mexico

Dudleya campanulata is a species of perennial succulent plant known by the common name as the Punta Banda liveforever, native to Baja California and endemic to the Punta Banda peninsula, a promontory south of Ensenada that encloses the southern limit of the Bahía de Todos Santos, a deepwater bay. One of many species of Dudleya native to the peninsula and surrounding islands, it is distinguished by its campanulate flowers and its occupation of a narrow habitat that consists of ocean bluffs on the southern end of the Punta Banda, near the well-known blowhole La Bufadora.

Dudleya formosa, known by the common name La Misión liveforever, is a species of perennial succulent plant endemic to the Guadalupe Valley in Baja California. It is characterized by bright green leaves, red floral stems, and pink flowers.

<i>Dudleya saxosa <span style="font-style:normal;">subsp.</span> collomiae</i>

Dudleya saxosa subsp. collomiae, known by the common name Gila County liveforever, is a subspecies of perennial succulent plant within the genus Dudleya native to central Arizona. It is characterized by showy bright-yellow flowers on an upright inflorescence colored pink, red or orange. The leaves are green or covered in a white, powdery wax. This species is found growing in rocky slopes, canyons, and crevices, and often on Sonoran Desert sky islands.

<i>Dudleya nubigena</i> Species of succulent plant from Mexico

Dudleya nubigena is a species of succulent plants in the family Crassulaceae. It is a rosette forming perennial with flattish leaves. Endemic to southern Baja California Sur, the species is found in the Sierra de la Laguna and the surrounding lowlands, and on Cerralvo Island.

<i>Dudleya abramsii <span style="font-style:normal;">subsp.</span> affinis</i> Subspecies of plant

Dudleya abramsii subsp. affinis, commonly known as the San Bernardino Mountains Dudleya, is a subspecies of succulent plant endemic to a portion of the San Bernardino Mountains in California. It is a plant with an unbranching stem and elliptical leaves occurring in Green Canyon and the nearby plateaus.

<i>Dudleya cymosa <span style="font-style:normal;">subsp.</span> paniculata</i> Species of succulent plant

Dudleya cymosa subsp. paniculata, known by the common name Diablo Range dudleya, is a species of perennial succulent plant in the family Crassulaceae native to the Inner South Coast Range of California. It is characterized by pale yellowish flowers, oblong to oblanceolate leaves and a growth habit not limited to a single substrate. It is closely related to Dudleya abramsii subsp. setchellii.

Dudleya cymosasubsp. costatifolia, known commonly as the Pierpoint Springs dudleya or the Pierpoint Springs liveforever, is a species of succulent plant in the family Crassulaceae, narrowly endemic to a locality in Tulare County, California, United States. It is a clumping plant with small rosettes and bright yellow flowers, resembling alpine cushion plants.

<i>Dudleya cymosa <span style="font-style:normal;">subsp.</span> pumila</i> Subspecies of plant

Dudleya cymosasubsp. pumila, most commonly known as the low canyon dudleya, chalky canyon dudleya or California live-forever, is a species of perennial succulent plant. It has diamond to spoon shaped leaves, sometimes coated with a fine white powder, and in May through July, bright red, orange or yellow flowers adorn the short inflorescence. A leaf succulent primarily found growing in rocky cliffs and slopes, it is endemic to California, and grows in the Transverse Ranges and South Coast Ranges, with some outlying populations. A variable plant, in some localities it is difficult to distinguish from other plants in the genus.

<i>Dudleya saxosa <span style="font-style:normal;">subsp.</span> aloides</i> Subspecies of perennial succulent plant

Dudleya saxosasubsp. aloides is a species of perennial succulent plant in the family Crassulaceae known by the common names desert dudleya or desert savior. It is a rosette-forming species widely distributed throughout the Peninsular Ranges and desert mountains of California in the United States. It is characterized by bright-yellow or greenish-yellow flowers, and can be found in shaded crevices and slopes. Plants in western half of the range may grade into Dudleya lanceolata.

<i>Dudleya cymosa <span style="font-style:normal;">subsp.</span> cymosa</i> Subspecies of succulent perennial plant

Dudleya cymosasubsp. cymosa is a species of succulent perennial plant in the family Crassulaceae native to California. It is the autonymous subspecies for Dudleya cymosa, and is known by the common name canyon liveforever. It is native to the California Coast Ranges, the Sierra Nevada and the Santa Monica Mountains. It is characterized by bright-yellow, orange or red flowers and broad, wide leaves. This plant is commonly found growing on rocky outcrops, talus slopes, and in shaded canyons.

<i>Dudleya saxosa <span style="font-style:normal;">subsp.</span> saxosa</i> Plant species

Dudleya saxosasubsp. saxosa is a species of succulent perennial plant endemic only to the western Panamint Range of California. It is known commonly as the Panamint liveforever or Panamint dudleya. It is found on north-facing, granitic or limestone slopes and grows up to 20 cm wide. It is characterized by bright yellow, red tinged flowers, which bloom from May to June.

References

  1. "Dudleya virens subsp. extima". Plants of the World Online . Royal Botanic Gardens, Kew . Retrieved 15 February 2022.
  2. 1 2 Rebman, J. P.; Gibson, J.; Rich, K. (2016). "Annotated checklist of the vascular plants of Baja California, Mexico" (PDF). San Diego Society of Natural History. 45: 134.
  3. 1 2 3 Moran, Reid (1996). The Flora of Guadalupe Island. California Academy of Sciences. pp. 100–101. ISBN   0-940228-40-8.
  4. 1 2 3 4 5 6 Moran, Reid (1995). "The Subspecies of Dudleya virens (Crassulaceae)". Haseltonia. 3: 1–9.
  5. 1 2 Yost, Jenn M.; Bontrager, Megan; McCabe, Stephen Ward; Burton, Darren; Simpson, Michael G.; Kay, Kathleen M.; Ritter, Matt (2013-12-01). "Phylogenetic Relationships and Evolution in Dudleya (Crassulaceae)". Systematic Botany. 38 (4): 1096–1104. doi:10.1600/036364413X674760. S2CID   15715233. Dudleya virens subsp. insularis (Rose) Moran and D. v. subsp. virens (Rose) Moran are strongly supported as sister taxa (1.0 BI PP; Fig. 1) but are not allied with D. v. subsp. extima Moran. Instead, D. guadalupensis Moran and D. v. subsp. extima are strongly supported as sister taxa (1.00 BI PP; Fig. 1).The same relationship is recovered in the nrDNA tree (Fig. 2).The cpDNA tree shows moderate support (0.88 BI PP)for a paraphyletic D. virens, with D. guadalupens is embedded within D. virens (Fig. 3).
  6. Moran, Reid; Lindsay, George (January 1950). "Guadalupe Island". Desert Plant Life. 22: 3–9 via archive.org.