Dudleya pachyphytum

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Cedros Island liveforever
Dudleya pachyphytum in the garden.jpg
A cultivated plant with emerging floral stems
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Order: Saxifragales
Family: Crassulaceae
Genus: Dudleya
Species:
D. pachyphytum
Binomial name
Dudleya pachyphytum
Moran & M.Benedict

Dudleya pachyphytum is an insular succulent plant known by the common name Cedros Island liveforever. It is a member of the genus Dudleya, in the family Crassulaceae. Characterized by thick, blunt leaves covered in a white, powdery wax and adorned by white flowers in bloom, it is regarded as one of the most attractive and charismatic members of its genus. It is endemic to the foggy northern end of Mexico's Cedros Island, occupying an ecological niche shared with the Cedros Island Pine. [2] [3]

Contents

The plant is endangered due to poaching from organized criminals supplying succulent collectors, many of whom are located in Asia. [4] [5] The poachers include South Korean nationals and criminal gangs operating under the Mexican cartels. The demand from succulent collectors has led to overexploitation of the plant in the wild, and armed confrontations between competing poachers has contributed to several killings. [6] [7] [8]

Description

This plant is characterized by its distinctive appearance that stands in stark contrast to other Dudleya, as it has extremely thick, blunt, turgid leaves and a pale, desaturated inflorescence. The leaves of this species are the thickest in the genus, making it easily recognizable among the other members. [9] It bears resemblance in the rosette, epicuticular wax and thick leaves to other maritime Dudleya, like D. caespitosa of the central Californian coast, D. candida of the Coronado Islands, and D. farinosa of the northern coast of California, and D. greenei of the Channel Islands. [10]

Vegetative morphology

An image of the characteristic rosettes of Dudleya pachyphytum in the garden. Dudleya - Vince Scheidt.jpg
An image of the characteristic rosettes of Dudleya pachyphytum in the garden.

Dudleya pachyphytum plants can be up to 7 decimeters (dm) wide, with 10 to 50 clusters of rosettes. Caudices are 4 dm or more long, decumbent in age, and 2 to 5 centimeters thick. Dead and dry leaves around 10 cm thick clothe the caudex. [10]

Rosettes are compact, 12 to 22 cm. wide, with 12 to 25 leaves but up to 55 in cultivated specimens. Leaves are farinose, thick and turgid, ovate to oblong and broadest near the base, rounded to broadly obtuse, and apiculate. The dimensions of the leaf are 5 to 10 cm. long, 3 to 5 cm. wide, and 1.5 to 2.5 cm. thick. Ventrally, the leaves are flattish, with prominent low ridges corresponding to the edges of adjacent leaves in bud. Dorsally, the leaves are rounded and asymmetrically low-keeled, with the margins obtuse near the base to rounded above. [10]

Reproductive morphology

The nascent inflorescence of Dudleya pachyphytum. Dudleya pachyphytum in the garden 3.jpg
The nascent inflorescence of Dudleya pachyphytum.

Floral stems are erect or spreading, 2 to 5 dm long, 5 to 15 mm thick to 18 mm wide at the base, farinose, and colored a pale pink that becomes red lower on. 20 to 35 bracts are present on the floral stem. The bracts are cordate-ovate, clasping, and broadly acute, about 1 to 2.5 cm long and wide, and 3 to 13 mm thick. [10]

The inflorescence is cernuous in bud, but it later becomes erect and rather dense. Inflorescence is 8 to 14 cm wide, with 3 to 6 close-set bifurcate [lower-alpha 1] branches. The cincinnus is circinate (unfurling like a fern's frond, see circinate vernation), with 5 to 12 flowers. The pedicels are erect, about 2 to 6 mm long, and 1 to 2.5 mm thick at the base, thickening upward. [12]

On the flower, the calyx is rounded below, 5 to 9 mm long, and 4.5 to 7 mm wide, with appressed segments. Calyx segments are triangular-lanceolate, acute, and 4 to 7 mm long, 2.5 to 4 mm wide. Corolla is white, 8 to 11 mm long, 4 to 5 mm thick, with the petals connate 2 to 3 mm and erect with the tips slightly outcurved, elliptic to oblong, acute, 2 to 3mm wide. Inside the flower, the filaments are white. Epipetalous stamens are 5 to 8 mm long, whilst the antesepalous stamens are 6.5 to 9 mm long. Before dehiscence, anthers are red, 1.2 to 1.4 mm long. The nectaries are white and 0.9 to 1.2 mm wide. Gynoecium is 7 to 10 mm high, 2 to 3 mm thick, with the pistils erect, appressed, and connate around 2 mm ventrally, tapering into styles about 1.5 to 2mm long. There are 25 to 45 ovules, 0.4 to 0.5 mm long. [13]

Seeds are about 0.6 mm long, with around 15 longitudinal striations. [13]

Taxonomy

Taxonomic history

Dudleya pachyphytum was discovered by Michael Benedict, a research associate at the Santa Barbara Botanic Garden, during a trip to Cedros Island in 1971. Benedict found an uprooted rosette in a ravine known as Cañada de la Mina, [lower-alpha 2] near the Punta Norte lighthouse on the northern end of the island. Presumably, the rosette had tumbled down the cliffs and into the ravine, where Benedict found it. Excited about his new discovery, Benedict hiked about attempting to find another plant, but his efforts were fruitless. [15]

Benedict returned in 1977, bringing some back to flower in Santa Barbara. Towards the end of the decade, natural history tours of Cedros Island, particularly in the northern half, brought more attention to this then undescribed species. [2] The unknown species was further propelled into the limelight after Alfred B. Lau of the Cactus and Succulent Society of America returned with colored pictures and analysis of the species. [16] Finally, after the suggestion of Lau, Benedict, Reid Moran, and their colleagues returned to Cedros Island in 1980, describing and publishing the species Dudleya pachyphytum in Phytologia. This plant was named pachyphytum owing to the resemblance of its thick leaves to another genus in the stonecrop family, Pachyphytum , also native to Mexico. [17]

Phylogeny

Phylogenetic analysis of the genus Dudleya places D. pachyphytum in a clade with D. linearis, the San Benito Islands liveforever, a relative that is endemic to the San Benito Islands, and D. brittonii , Britton's liveforever, endemic to the northern coastal cliffs of Baja California. [18]

Distribution, habitat and ecology

Distribution

Cedros Island and surrounding geographical features. Cedros.jpg
Cedros Island and surrounding geographical features.

Dudleya pachyphytum exists on the northern end of Cedros Island, the largest of the Baja California's islands on the Pacific coast. In the fog zone, near groves of Pinus radiata , it occurs at an elevation about 100 to 500 m (328 to 984 ft), often with north to northwest-facing exposure. From the Punta Norte, its distribution continues at least 3 km south on the western flank of the island, down to 100 m (328 ft). The southern limit on the species is near the ridges of Cañada de la Mina, and explorations by botanists indicate that the species is probably expanding southwards. [2] It coexists on the island with other species of Dudleya, including D. acuminata , D. albiflora , and D. cochimiana . [3]

Habitat

Detail of the bracts on the developing floral stems and some of the rosette leaves of Dudleya pachyphytum. Dudleya pachyphytum in the garden 2.jpg
Detail of the bracts on the developing floral stems and some of the rosette leaves of Dudleya pachyphytum.

The succulent occupies an ecological niche at the northern end of Cedros Island, where the predominantly arid foliage gives away to pines, lichen, and D. pachyphytum, fed by the moisture brought by the marine fog. The seaward slopes are often so saturated by cool marine winds that the temperature often remains close to the dew point. It is primarily an occupant of rocky slopes and cliffs, albeit occasional specimens grow in the duff of the pine forest, and those that do often grow vigorously, with 5 to 10 seedlings emerging from the clearings in the forest floor. Below the pine forest, in the sea cliffs and weathered slopes, among the scree of frequent rockfall, D. pachyphytum forms an association with Bahiopsis lanata, a member of the family Asteraceae. As noted by one of the describers of the species, Reid Moran, one of the reasons D. pachyphytum may be so successful on the talus slopes is because of their ability to roll in the event of disturbance, eventually re-rooting after they land in a suitable position. [2] [19]

Analysis of the vegetation communities on Cedros Island places D. pachyphytum in its own community, the Northern Bluff Succulent Community, wherein D. pachyphytum makes up 15 to 20% of the plant cover. [20]

Associated species of the Northern Bluff Succulent Community [20]

Pests and diseases

Several animals feed on D. pachyphytum. Larvae of the Sonoran blue butterfly feed on the inflorescence, and many of the developing floral stems are presumably eaten by the Cedros Island black-tailed deer. [2]

Conservation and poaching

Although in the late 20th century the population of Dudleya pachyphytum was thought to be growing, as the range was expanding towards the south, [2] anthropogenic factors, primarily owing to poaching and demand from foreign succulent collectors, have been detrimental for the future of the plant. Since Alfred B. Lau's pictures of the plant appeared in the Cactus and Succulent Journal of America in the 1980s, poachers have been stealing the plant from Cedros Island and botanical gardens, including one of the original collections from before the species description. [2] However, the scale of poaching has drastically increased in the 20th century to an unprecedented level.

One plant grown for six years in Santa Barbara had a rosette of about 55 leaves—when a thief interrupted the study.

Reid Moran and Michael Benedict, in reference to the theft of a plant used for research, [2]

Accessing the habitat D. pachyphytum grows in is difficult, as the northern part of the island consists of steep, narrow mountains with peaks up to 3,400 ft (1,000 m) high, with the slopes covered in spiny cacti and agaves. In addition to accessing the island in the first place, once at the northern part of the island, it takes a 2 mi (3.2 km) hike with an elevation gain of 2,000 ft (610 m) in a landscape with no trails just to reach the plants. To circumvent this difficulty, it has been reported that poachers have utilized a helicopter to land on a ridge and take the plants. [21]

Owing to the difficulty of collecting this plant in the wild, combined with crackdowns on its poaching by the Mexican government, some poachers have instead focused on stealing a related plant, Dudleya farinosa , native to the west coast of the United States, labeled by Dudleya expert and botanist Stephen W. McCabe as "a poor man's pachyphytum." Although D. farinosa is much more widespread, the level of poaching can devastate local populations. [15] [21]

Demand for D. pachyphytum is primarily motivated by international consumers, often succulent collectors and enthusiasts, mostly based in East Asia, particularly South Korea and China. [22] [4] In 2016, South Korean nationals began moving to Bahía Tortugas, on the coast of Baja California Sur, to facilitate the poaching of the plants via a network of paid operatives. [5]

2017 seizure of Dudleya pachyphytum in Baja California

In 2017, Mexican authorities from the Secretariat of National Defense (SEDENA), and the Federal Attorney for Environmental Protection (PROFEPA) stopped a theft of nearly 4,756 rosettes of D. pachyphytum. At a military checkpoint "Chula Vista" in the vicinity of the Baja California and Baja California Sur border, members of the SEDENA discovered a 55-ft long Freightliner tractor trailer loaded with 64 boxes of the poached succulent. 3 South Korean nationals and 1 Mexican national were apprehended. The succulents were discovered in poor condition, and were moved to the mainland to be rehabilitated. [8] [23]

2018 seizure of Dudleya pachyphytum in La Paz

In June 2018, customs officials at La Paz International Airport discovered 30 boxes of D. pachyphytum being shipped to Cuautla, Morelos. 493 specimens of the plant were destined to be shipped to a nursery in Morelos, from which they were allegedly to be sold in South Korea. [24]

2018 murders of Bahía Tortugas fishermen

In November 2018, seven fishermen from Bahía Tortugas in Baja California Sur were reported missing, after a trip to Cedros Island, 36 mi (58 km) away. The Mexican Navy initiated a search and rescue operation after the Mulegé delegate relayed the case of the missing fishermen, sending a patrol and a King Air 350 surveillance aircraft. [25] Soon after, a member of the Guardia Estatal de Seguridad e Investigación of Baja California discovered the injured 29 year-old Cristóbal Emmanuel Arce Carranza, with gunshot wounds to his arms, who stated he had arrived at Punta Norte to poach D. pachyphytum for sale in the Asian market. [26] That same day, one of the fishermen, Antonio Herrera, was discovered unharmed, stating that the group had been attacked by armed, hooded men. Within a few hours, the body of the next victim, Fidencio Aguilar Espinoza, was discovered with gunshot wounds to the back and head. [6]

On December 5, two of the lost fishermen were rescued. Six days later, the corpse of the final member of the group, 32 year-old Iván Josué García Guzmán, was discovered in an advanced state of decomposition with his hands tied. The status of the seventh fisherman remained unknown. [27]

Some of the fishermen had links to members of criminal gangs operating in the area, and coupled with the fact that Cedros Island serves as a strategic link for transporting narcotics to the United States, investigators suspect the involvement of the Arellano-Félix Cartel, the Sinaloa Cartel, and possibly the Jalisco New Generation Cartel. [6] The commander of the Second Naval Region, Admiral Jorge Luis Cruz Ballado, concluded that the deaths were not the result of a shipwreck, but of an attack of the men collecting the plant by armed assailants. [28] The assailants were likely a cell of the Sinaloa Cartel known as "Los Venados," who targeted the fishermen owing to their links to an antagonistic group "Los Querreques." [7]

Notes

  1. In botanical terms, bifurcation means having two branches or divisions arise from a common point. One example would be the prongs of a fork. [11]
  2. Named after a copper mine established on Cedros Island by an American, George P. Brown. [14]

See also

Other maritime Dudleya species:

Dudleya of Cedros Island:

Related Research Articles

<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, 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 candelabrum</i> Species of succulent plant from the U.S.

Dudleya candelabrum is a species of succulent plant known by the common names candleholder liveforever or candleholder dudleya. Endemic to California, this species grows wild only on the northern Channel Islands, where it is found in open rocky places and north-facing slopes. It is characterized by thin, spade-shaped green leaves and an inflorescence covered in long, reflexed bracts, with pale yellow flowers. It has been threatened by poachers shipping plants to South Korea.

<i>Dudleya pulverulenta</i> Species of succulent plant found in the U.S. and Mexico

Dudleya pulverulenta is a species of perennial succulent plant known by the common names chalk lettuce, chalk dudleya, and chalk liveforever. It is one of the largest Dudleya, with a silvery, waxy rosette that may greatly contrast with its habitat. It is also regarded as one of the most distinctive members of the Dudleya, with the most advanced inflorescence in the genus, consisting of pendant, hummingbird pollinated flowers, the longest corolla, and the highest nectar output, along with the largest range of all the Dudleya, over 1,000 kilometres (620 mi), being found from southern Monterey County in California to the Sierra de San Borja in southern Baja California.

<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 variegata</i> Species of succulent

Dudleya variegata is a deciduous succulent plant in the family Crassulaceae known by the common names variegated liveforever, variegated dudleya or rarely San Diego Hasseanthus. A cryptic plant that survives part of the year dormant underground from starch reserves in a corm, after sufficient rainfall, leaves will emerge, soon giving way to small inflorescences with yellow star-shaped flowers. It is native to Baja California and adjacent San Diego County in California, where it grows in several habitat types, including chaparral and vernal pools.

<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 ingens</i> Species of succulent

Dudleya ingens is a species of perennial succulent plant in the family Crassulaceae commonly known as the rock liveforever or Baja liveforever. A relatively large member of the genus Dudleya, this species has long green succulent leaves, and in April to June is characterized by pale yellow to white pink-tinged flowers topping tall, reddish inflorescences. It has a stem clothed densely with old, leathery leaves, and the inflorescence may be nodding, with the floral branches bearing the flowers tending to unfurl like the fronds of a fern. It is similar in appearance to Dudleya brittonii, but differs in range and chromosome number. This species is endemic to the state of Baja California in Mexico, being found from Santo Tomás to the southern coast of the state.

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

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 anomala</i> Species of plant

Dudleya anomala is a rare species of succulent plant in the family Crassulaceae commonly known as the Todos Santos liveforever. With a dense, cushion-forming habit, this leaf succulent is characterized by elongated stems, slightly sticky leaves, and bell-shaped flowers with white, spreading petals. This species is native to Baja California, Mexico, and is found primarily on islands and one coastal locality.

<i>Dudleya gatesii</i> Species of succulent plant

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<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.

<i>Dudleya linearis</i> Species of succulent plant

Dudleya linearis is an insular succulent plant known by common name as the San Benitos Liveforever. It is endemic to the San Benito Islands, a small group of Mexican islands in the Pacific Ocean, west of Cedros Island. The population was almost wiped out by rabbits introduced to the island.

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 cultrata</i> Species of succulent

Dudleya cultrata is a species of perennial succulent in the family Crassulaceae commonly known as the knife-leaved liveforever or the maritime succulent liveforever. This species is characterized by oblong, narrow green leaves and flowers with pale yellow petals that bloom from April to June. Although similar to Dudleya ingens, this species is most often seen growing sympatric with the larger, wax-covered Dudleya anthonyi. It is native to Baja California, occurring on the coast from Punta Colonet and San Quintin to El Rosario.

<i>Dudleya arizonica</i> Species of perennial

Dudleya arizonica is a species of perennial succulent plant commonly known as the Arizona chalk dudleya and the Arizona liveforever. A member of the genus Dudleya, this species is characterized by long, red flowers that adorn a waxy rosette of succulent leaves. It resembles a reduced desert form of the more coastal chalk dudleya, Dudleya pulverulenta, but differs in its smaller stature, lower number of leaves, and orientation of the flowers. Native to the southwestern United States and northwestern Mexico, it is widespread in range, but is primarily found in scattered, widely separated localities. It can be found as far west as coastal Ensenada to the desolate desert ranges of Nevada. It is one of two species of Dudleya that occur in Arizona, the other being Dudleya saxosa subsp. collomiae, and is the only species on mainland Mexico and in Utah.

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

Dudleya acuminata is a species of succulent perennial plant in the family Crassulaceae known by common name as the Vizcaino liveforever. A rosette-forming leaf succulent, it has reddish yellow flowers that emerge from April to May. It is native to the Pacific coast of the Vizcaino Desert on the Baja California Peninsula, and on neighboring islands.

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

Dudleya cochimiana, commonly known as the Cochimíliveforever, is a species of succulent plant in the family Crassulaceae endemic to Cedros Island, a large island off of the coast of Baja California, Mexico. It is a rosette-forming leaf succulent characterized by broad, green to white leaves, and flowers with white to pink petals. It can be found on rocky slopes and canyons along the island.

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

Dudleya albiflora, known by the common name white-flower liveforever, is a species of succulent perennial plant in the family Crassulaceae. It is native to the Baja California Peninsula. This species represents numerous populations with varying chromosome numbers scattered around the peninsula, but all share broad, common morphological traits such as white flowers and narrow leaves.

Dudleya virens subsp. extima is a subspecies of succulent plant in the family Crassulaceae commonly known as the Guadalupe green liveforever. 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. It closely resembles a miniature version of Dudleya virens subsp. virens, but it may be more nearly related to the local Dudleya guadalupensis.

References

Citations

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  • 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: 133.
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  • Margulies, Jared D. (2020). "Korean 'Housewives' and 'Hipsters' Are Not Driving a New Illicit Plant Trade: Complicating Consumer Motivations Behind an Emergent Wildlife Trade in Dudleya farinosa". Frontiers in Ecology and Evolution. 8. doi: 10.3389/fevo.2020.604921 . ISSN   2296-701X.

News articles:

Governmental documents and articles: