［概要性翻译］Echeveria juliana 朱丽安娜
First published in Haseltonia 18: 52-55, 2012
本文首次发表于Haseltonia 18: 52-55, 2012，一切权利属于原作者
转载请注明译者
作者：
JERóNIMO REYES SANTIAGO
OMAR GONZáLEZ ZORZANO
Jardín Botánico
MARTIN KRISTEN
翻译（概要性，非全文）：Qiuhan
Abstract: Echeveria juliana is described as a new species based on collections in the Rio Piaxtla Canyon, in the Sierra Madre Occidental near the border between the Mexican states of Sinaloa and Durango. This species
appears to be related to E. tobarensis from Durango. It differs in the size of the rosette, its pale pink color, shape and pruinosity, as well as corolla size, color of the carpels, and its obovate leaves. The new species grows at an uncommonly low altitude of 360 m (1080 ft) in tropical deciduous forest. It belongs into the series Urbiniae as it lacks an evident stem or tuberous roots, and by the possession of a secund inflorescence and a long urceolate corolla.
摘要：Echeveria juliana（朱丽安娜）是在Rio Piaxtla峡谷发现的新物种，这个峡谷位于Madre Occidental山脉，就在墨西哥Sinaloa州和Durango州的交界处。这个物种与来自Durango州的拓跋莲有一定亲缘关系，但莲座的大小、淡粉色的颜色、形状、被白霜的特点、花冠的大小、心皮的颜色和倒卵形的叶片都与拓跋莲不同。该新物种生长在约海拔360米的热带落叶林中，海拔罕见地低。由于没有明显的茎干或块茎，有偏向一侧的花序和长长的瓮状花冠，它应属于瓮花系。
Fieldwork and identification of Mexican Crassulaceae have occasioned the following novelty:
Echeveria juliana Reyes, González-Zorzano & Kristen sp. nov., Figs.
Echeveria juliana similis E. tobarensi sed rosulis 13?18 cm diam. (vs. 6?12 cm), foliis obovato-oblanceolatis, acuminato-caudatis, pruinosis, pallide roseis (vs. ovatis, acute acuminatis, glabris, griseo luridis), caulibus floralibus pallide roseis (vs. griseis), pedicellis 4?9 mm longis (vs. 5 mm), sepalis 2.0?2.5 mm longis, ovatis (vs. 1.0?1.2 mm, triangulari-ovatis), corolla longe urceolata (vs. urceolata), antheris ochraceis (vs. viridibus), carpellis viridibus (vs. albis), nectariis squamiformibus (vs. reniformibus) differt.
Perennial herb. Roots fibrous. Stem hardly evident, to 2.7 cm long, 1–1.3 cm thick. Rosettes 13–18 cm wide. Leaves light pink, obovate to oblanceolate, glaucous to pruinose, margin entire, slightly hyaline, apex acuminate to caudate, 4.5–8.0 cm long, 2.5–3.8 cm wide, ca. 1 cm thick at the middle. Floral stems 1–2 per rosette, erect, to about 50 cm long including cincinni, leaves lanceolate, light pink, glaucous. Inflorescence paniculate, of 2 cincinni with 17–23 flowers, bracts lanceolate, 2–4 mm long, 1–2 mm wide, pruinose, pink. Pedicels 4–9 mm long, ca. 1 mm thick, descending to slightly ascending, pink, pruinose. Flowers: Calyx discoid, 2.5–3.5 mm thick; sepals equal, adpressed, triangular-ovate, 2.0–2.5 mm long, ca. 1 mm thick, pruinose, acute. Corolla urceolate to long urceolate, somewhat pentagonal, 10?12 mm long, ca. 4 mm thick at base, pruinose and pale pink; petals connate at base, lanceolate, acute and apiculate, 10?12 mm long, ca. 2.4?2.6 mm wide in the middle. Androecium: filaments whitish, with 5 epipetalous stamens 2.8–3.0 mm long including theca, and 5 antisepalous stamens 3.0–3.2 mm long, anthers green. Gynoecium 5.0–5.2 mm long including style, ca. 3.6 mm wide, yellowish green, stigma yellowish green. Nectar scales squamiform, 2.2 mm long, 1 mm wide, white.
Type: Mexico, Sinaloa: along river banks of Rio Piaxtla west of the mining town of Tayoltita (Durango), municipality of San Ignacio, 359 m. 8 May 2010. J. Etter & M. Kristen 3056. (Holotype: MEXU.)
Phenology: Plants bloom in April and May in habitat and in the greenhouse.
Distribution and Habitat: Echeveria juliana grows in tropical deciduous forest on the banks of the Rio Piaxtla. The predominant associated species are: Bursera spp., Plumeria rubra L., Pseudobombax sp., Agave vilmoriniana Berger, A. aff. filifera, Echinocereus aff. koehresianus (G. Frank) W. Rischer, Pilosocereus alensis (F.A.C. Weber ex Roland-Gosselin) Byles & G.D. Rowley, Pachycereus pecten-aboriginum (Engelmann) Britton & Rose, and Hechtia sp.
Etymology: The name of the species honors Julia Etter for her dedication and courage in venturing into the remote back country of Mexico in search of Crassulaceae and Agavaceae. She has made significant contributions to science in searching for plants in the field and helping to enlarge the National Collection of Crassulaceae at the Botanical Garden (IB-UNAM) and the Mexican National Herbarium (MEXU) as well as maintaining the free web database www.crassulaceae.com.
描述：
多年生草本植物。
根部：须根。
茎部：不明显，长可达2.7cm，1-1.3cm粗。
莲座：13-18cm
叶：淡粉色，倒卵形-倒披针形，表面微霜或被白霜，全缘，叶缘微透明，顶部有尖，4.5-8cm长，2.5-3.8cm宽，中部约1cm厚。
花序：每个莲座可生出1-2根花序，直立，可达50cm长，上有披针状叶，淡粉色，微霜。蝎尾状聚伞花序，2根分枝，每根上17-23朵花，苞叶披针形，2-4mm长，1-2mm宽，被霜，粉色。花梗4-9mm长，约1mm厚，向下或略微向上伸展，粉色，被霜。
花：花萼平圆形，2.5-3.5mm厚；萼片等长，紧贴花瓣，三角形-卵形，2-2.5mm长，约1mm厚，被霜，有尖。花冠瓮形或长瓮形，略偏五角形，10-12mm长，基部约4mm粗，被霜，但绯色；花瓣在基部合生，披针形，微尖， 10-12mm长，中部约2.4-2.6mm宽
模式标本产自墨西哥的Sinaloa省的一条河岸上，海拔359米。
这个物种生长河岸边的在热带落叶林中，当地其他物种主要包括一些橄榄科物种、红花缅栀（好像就是一种鸡蛋花啦）、假木棉属植物、一种龙舌兰、鹿角柱属和摩天柱属的一些植物。
花期：4-5月。
这个物种的名字是为了向Julia Etter致敬，她常年在墨西哥荒僻的腹地上搜寻景天科和龙舌兰科的植物，为之付出了巨大的勇气和热情。她为植物自然栖息地方面的科学研究做出了卓越的贡献，并协助National Collection of Crassulaceae at the Botanical Garden (IB-UNAM)和墨西哥国家植物标本馆（MEXU）扩大收藏范围，还维护着一个免费的在线数据库http://www.crassulaceae.com。
DISCUSSION
详述
In 2009 the team of Julia Etter and Martin Kristen, collaborators of the Instituto de Biología, Universidad Nacional Autónoma de México (UNAM) and members of the Sociedad Mexicana de Cactología, A.C., made an exploratory field trip to the states of Durango and Sinaloa in search of species of the Crassulaceae and Agavaceae. At one of their frequent stops along the Piaxtla River they found high up on the river bank below an Agave sp. a beautifully colored Echeveria species. As very few echeverias are known to grow at such low altitudes, specimens were collected and sent back to the Botanical Garden of the Instituto de Biología, IB-UNAM, for further study and cultivation.
2009年，Julia Etter和Martin Kristen二人组和其他一些机构的人去Durango地区进行了一次田野调查，想要找些景天科和龙舌兰科的物种。在Piaxtla河边他们发现岸边高处有一棵龙舌兰和一颗颜色十分漂亮的拟石莲属物种。要知道，很少有拟石莲属物种会长在海拔这么低的地方，所以这颗标本被小心地采集并送回了Julia和Martin供职的植物园。
The plants did not produce flowers at UNAM due to infections of the flowering stems. However, the backup copy in the UNAM plant collection at the home of Julia and Martin in the Mexican state of Jalisco produced flowers and detailed close-up photos
were taken. The photographs of the inflorescence and the flower suggested that it might be Echeveria tobarensis (Rose) Berger, recently rediscovered near Tepehuanes, Durango (Etter & Kristen 2011). After other trips in 2010 to the locations of Echeveria tobarensis and Echeveria sp. in the Piaxtla river valley, and after studying the species in question closely it was concluded that the differences of the two Echeveria species justifies its recognition as a new species.
由于花序染病，这颗被带回植物园的标本并没能开花。但是，Julia和Martin家里的备份成功开花了，还留下了详尽的影像资料。照片上的花序和花朵形态证明它不是新近在Durango发现的拓跋莲（同样是Julia和Martin的功劳）。2010年再访拓跋莲和这个新物种的产地河谷时，他们又详尽地研究了这两个物种，并认为他们确实是不同的，新发现的这一株应该是一个新物种。
The new species, Echeveria juliana, is placed in series Urbiniae for its lack of an evident stem or tuberous roots and because of its secund inflorescence and urceolate corolla. It is easily distinguished from its apparently closer relative, Echeveria tobarensis, by the size of the rosette, its pruinose leaf surface, light-pinkish leaf color, size of the inflorescence and the color and shape of the flowers, and color of the anthers, nectaries and gynoecium (see Table 1).
这个新物种Echeveria juliana因为没有明显的茎部和块根、有着偏向一侧的花序和瓮状的花冠，而被归入瓮花系。它与近亲拓跋莲也有显著的不同，包括莲座的大小、叶子是否被霜、淡粉色的叶子、花序的程度和花朵的形色都可以看出区别。
Echeveria juliana is known only from the type locality in tropical deciduous forest at 359 m (1080ft) altitude, whereas its recently rediscovered closest relative, E. tobarensis, grows at more than 2020 m (6630 ft) in pine forests (Etter & Kristen 2011). Unlike E. tobarensis, E. juliana does not tolerate low temperatures in cultivation. There are only a few echeverias known so far that grow below 1500 m (4920 ft) in the mountains of the Pacific slope: E. pallida Walther at 140 m (460 ft), E. laui Moran & Meyrán at 550 m (1800 ft), and E. acutifolia Lindley usually between 200 and 1000 m (660–3280 ft). Most of the Echeveria species are therefore found in temperate zones. E. juliana is the only species known so far in northwestern Mexico growing below 400 m (1310 ft).
就目前所知，E. juliana只在模式标本产地栖息，那是一个海拔359米的热带落叶林，而它的近亲拓跋莲却生长在海拔2020米以上的针叶林中。不像拓跋莲，juliana无法忍受低温。截至目前，已知的拟石莲中只有为数不多的几种生长在海拔1500米以下面向太平洋的山坡，他们是霜之鹤（140米）、雪莲（550米）和E. acutifolia（通常200-1000米之间）。大部分拟石莲属植物其实都生长在温带环境下。E. juliana实际上是唯一已知长在墨西哥西北部海拔400米以下的物种。
The changes in geomorphology and morphoclimate are the result of various volcanic activities, products of long and intense geologic activity during the Cretaceous and Cenozoic periods. These changes caused geographic and genetic isolation in many populations of species of the Crassulaceae family. This can be seen in the richness and the endemism of different species of the Sierra Madre Occidental such as Sedum lumholtzii Robinson & Fernald, S. bellum Rose ex Praeger, S. kristenii Reyes, González-Zorzano & Etter, S. spathulisepalum Clausen, S. trichromum Clausen, S. craigii Clausen, Villadia pringlei Rose, Graptopetalum filiferum (Watson) Whitehead, G. bellum (Moran & Meyrán) D.R. Hunt, among others. This region, one of the largest zones of igneous-silicate origins in the world, covers an area of 289,000 square kilometers with altitudes varying from 200 m to up to 3000 m (Ferrusquía 1998).
这种地理分布和形态方面的差异性是火山活动造成的，剧烈的地质变化导致景天科个物种间出现了地理隔离，进而演化出了不同的基因。Madre Occidental山脉那特有的丰富物种无疑是这一观点的最佳佐证。
ACKNOWLEDGMENTS
The authors thank Myron Kimnach for valuable comments and additional data that have improved the manuscript. They also thank Pablo Carrillo Reyes for revising the manuscript and for his thoughtful suggestions helping to improve this article. Our appreciation also goes to Enriqueta Molina of SINAREFI/SAGARPA for his support of the project “Red de Echeveria” in agreement with the Instituto de Biología de la Universidad Nacional Autónoma de México, and to SEMARNAT for the official federal collecting permit SEMARNAT SGPA/DGVS/02315/10.
各种致谢。
LITERATURE CITED
Etter J, Kristen M. 2011. The rediscovery of the elusive Echeveria tobarensis. Cact. Succ. J. (US) 83: 275–283.
Ferrusquía VI. 1998. Geología de México: una sinopsis.
In: Ramamoorthy TP, Bye R, Lot A. Diversidad biológica de México: orígenes y distribución. Universidad
Nacional Autónoma de México. México. Pp. 3−108.
各种引用。
原文下载：http://www.crassulaceae.ch/index.php?TPL=113&x270_id=2988&x270_listsearch=1
本文首次发表于Haseltonia 18: 52-55, 2012，一切权利属于原作者
转载请注明译者
作者：
JERóNIMO REYES SANTIAGO
OMAR GONZáLEZ ZORZANO
Jardín Botánico
MARTIN KRISTEN
翻译（概要性，非全文）：Qiuhan
Abstract: Echeveria juliana is described as a new species based on collections in the Rio Piaxtla Canyon, in the Sierra Madre Occidental near the border between the Mexican states of Sinaloa and Durango. This species
appears to be related to E. tobarensis from Durango. It differs in the size of the rosette, its pale pink color, shape and pruinosity, as well as corolla size, color of the carpels, and its obovate leaves. The new species grows at an uncommonly low altitude of 360 m (1080 ft) in tropical deciduous forest. It belongs into the series Urbiniae as it lacks an evident stem or tuberous roots, and by the possession of a secund inflorescence and a long urceolate corolla.
摘要：Echeveria juliana（朱丽安娜）是在Rio Piaxtla峡谷发现的新物种，这个峡谷位于Madre Occidental山脉，就在墨西哥Sinaloa州和Durango州的交界处。这个物种与来自Durango州的拓跋莲有一定亲缘关系，但莲座的大小、淡粉色的颜色、形状、被白霜的特点、花冠的大小、心皮的颜色和倒卵形的叶片都与拓跋莲不同。该新物种生长在约海拔360米的热带落叶林中，海拔罕见地低。由于没有明显的茎干或块茎，有偏向一侧的花序和长长的瓮状花冠，它应属于瓮花系。
Fieldwork and identification of Mexican Crassulaceae have occasioned the following novelty:
Echeveria juliana Reyes, González-Zorzano & Kristen sp. nov., Figs.
Echeveria juliana similis E. tobarensi sed rosulis 13?18 cm diam. (vs. 6?12 cm), foliis obovato-oblanceolatis, acuminato-caudatis, pruinosis, pallide roseis (vs. ovatis, acute acuminatis, glabris, griseo luridis), caulibus floralibus pallide roseis (vs. griseis), pedicellis 4?9 mm longis (vs. 5 mm), sepalis 2.0?2.5 mm longis, ovatis (vs. 1.0?1.2 mm, triangulari-ovatis), corolla longe urceolata (vs. urceolata), antheris ochraceis (vs. viridibus), carpellis viridibus (vs. albis), nectariis squamiformibus (vs. reniformibus) differt.
Perennial herb. Roots fibrous. Stem hardly evident, to 2.7 cm long, 1–1.3 cm thick. Rosettes 13–18 cm wide. Leaves light pink, obovate to oblanceolate, glaucous to pruinose, margin entire, slightly hyaline, apex acuminate to caudate, 4.5–8.0 cm long, 2.5–3.8 cm wide, ca. 1 cm thick at the middle. Floral stems 1–2 per rosette, erect, to about 50 cm long including cincinni, leaves lanceolate, light pink, glaucous. Inflorescence paniculate, of 2 cincinni with 17–23 flowers, bracts lanceolate, 2–4 mm long, 1–2 mm wide, pruinose, pink. Pedicels 4–9 mm long, ca. 1 mm thick, descending to slightly ascending, pink, pruinose. Flowers: Calyx discoid, 2.5–3.5 mm thick; sepals equal, adpressed, triangular-ovate, 2.0–2.5 mm long, ca. 1 mm thick, pruinose, acute. Corolla urceolate to long urceolate, somewhat pentagonal, 10?12 mm long, ca. 4 mm thick at base, pruinose and pale pink; petals connate at base, lanceolate, acute and apiculate, 10?12 mm long, ca. 2.4?2.6 mm wide in the middle. Androecium: filaments whitish, with 5 epipetalous stamens 2.8–3.0 mm long including theca, and 5 antisepalous stamens 3.0–3.2 mm long, anthers green. Gynoecium 5.0–5.2 mm long including style, ca. 3.6 mm wide, yellowish green, stigma yellowish green. Nectar scales squamiform, 2.2 mm long, 1 mm wide, white.
Type: Mexico, Sinaloa: along river banks of Rio Piaxtla west of the mining town of Tayoltita (Durango), municipality of San Ignacio, 359 m. 8 May 2010. J. Etter & M. Kristen 3056. (Holotype: MEXU.)
Phenology: Plants bloom in April and May in habitat and in the greenhouse.
Distribution and Habitat: Echeveria juliana grows in tropical deciduous forest on the banks of the Rio Piaxtla. The predominant associated species are: Bursera spp., Plumeria rubra L., Pseudobombax sp., Agave vilmoriniana Berger, A. aff. filifera, Echinocereus aff. koehresianus (G. Frank) W. Rischer, Pilosocereus alensis (F.A.C. Weber ex Roland-Gosselin) Byles & G.D. Rowley, Pachycereus pecten-aboriginum (Engelmann) Britton & Rose, and Hechtia sp.
Etymology: The name of the species honors Julia Etter for her dedication and courage in venturing into the remote back country of Mexico in search of Crassulaceae and Agavaceae. She has made significant contributions to science in searching for plants in the field and helping to enlarge the National Collection of Crassulaceae at the Botanical Garden (IB-UNAM) and the Mexican National Herbarium (MEXU) as well as maintaining the free web database www.crassulaceae.com.
描述：
多年生草本植物。
根部：须根。
茎部：不明显，长可达2.7cm，1-1.3cm粗。
莲座：13-18cm
叶：淡粉色，倒卵形-倒披针形，表面微霜或被白霜，全缘，叶缘微透明，顶部有尖，4.5-8cm长，2.5-3.8cm宽，中部约1cm厚。
花序：每个莲座可生出1-2根花序，直立，可达50cm长，上有披针状叶，淡粉色，微霜。蝎尾状聚伞花序，2根分枝，每根上17-23朵花，苞叶披针形，2-4mm长，1-2mm宽，被霜，粉色。花梗4-9mm长，约1mm厚，向下或略微向上伸展，粉色，被霜。
花：花萼平圆形，2.5-3.5mm厚；萼片等长，紧贴花瓣，三角形-卵形，2-2.5mm长，约1mm厚，被霜，有尖。花冠瓮形或长瓮形，略偏五角形，10-12mm长，基部约4mm粗，被霜，但绯色；花瓣在基部合生，披针形，微尖， 10-12mm长，中部约2.4-2.6mm宽
模式标本产自墨西哥的Sinaloa省的一条河岸上，海拔359米。
这个物种生长河岸边的在热带落叶林中，当地其他物种主要包括一些橄榄科物种、红花缅栀（好像就是一种鸡蛋花啦）、假木棉属植物、一种龙舌兰、鹿角柱属和摩天柱属的一些植物。
花期：4-5月。
这个物种的名字是为了向Julia Etter致敬，她常年在墨西哥荒僻的腹地上搜寻景天科和龙舌兰科的植物，为之付出了巨大的勇气和热情。她为植物自然栖息地方面的科学研究做出了卓越的贡献，并协助National Collection of Crassulaceae at the Botanical Garden (IB-UNAM)和墨西哥国家植物标本馆（MEXU）扩大收藏范围，还维护着一个免费的在线数据库http://www.crassulaceae.com。
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自然栖息地上的朱丽安娜 |
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自然栖息地上的朱丽安娜 |
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自然栖息地上的朱丽安娜 |
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人工养殖植株的花 |
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心皮 |
DISCUSSION
详述
In 2009 the team of Julia Etter and Martin Kristen, collaborators of the Instituto de Biología, Universidad Nacional Autónoma de México (UNAM) and members of the Sociedad Mexicana de Cactología, A.C., made an exploratory field trip to the states of Durango and Sinaloa in search of species of the Crassulaceae and Agavaceae. At one of their frequent stops along the Piaxtla River they found high up on the river bank below an Agave sp. a beautifully colored Echeveria species. As very few echeverias are known to grow at such low altitudes, specimens were collected and sent back to the Botanical Garden of the Instituto de Biología, IB-UNAM, for further study and cultivation.
2009年，Julia Etter和Martin Kristen二人组和其他一些机构的人去Durango地区进行了一次田野调查，想要找些景天科和龙舌兰科的物种。在Piaxtla河边他们发现岸边高处有一棵龙舌兰和一颗颜色十分漂亮的拟石莲属物种。要知道，很少有拟石莲属物种会长在海拔这么低的地方，所以这颗标本被小心地采集并送回了Julia和Martin供职的植物园。
The plants did not produce flowers at UNAM due to infections of the flowering stems. However, the backup copy in the UNAM plant collection at the home of Julia and Martin in the Mexican state of Jalisco produced flowers and detailed close-up photos
were taken. The photographs of the inflorescence and the flower suggested that it might be Echeveria tobarensis (Rose) Berger, recently rediscovered near Tepehuanes, Durango (Etter & Kristen 2011). After other trips in 2010 to the locations of Echeveria tobarensis and Echeveria sp. in the Piaxtla river valley, and after studying the species in question closely it was concluded that the differences of the two Echeveria species justifies its recognition as a new species.
由于花序染病，这颗被带回植物园的标本并没能开花。但是，Julia和Martin家里的备份成功开花了，还留下了详尽的影像资料。照片上的花序和花朵形态证明它不是新近在Durango发现的拓跋莲（同样是Julia和Martin的功劳）。2010年再访拓跋莲和这个新物种的产地河谷时，他们又详尽地研究了这两个物种，并认为他们确实是不同的，新发现的这一株应该是一个新物种。
The new species, Echeveria juliana, is placed in series Urbiniae for its lack of an evident stem or tuberous roots and because of its secund inflorescence and urceolate corolla. It is easily distinguished from its apparently closer relative, Echeveria tobarensis, by the size of the rosette, its pruinose leaf surface, light-pinkish leaf color, size of the inflorescence and the color and shape of the flowers, and color of the anthers, nectaries and gynoecium (see Table 1).
这个新物种Echeveria juliana因为没有明显的茎部和块根、有着偏向一侧的花序和瓮状的花冠，而被归入瓮花系。它与近亲拓跋莲也有显著的不同，包括莲座的大小、叶子是否被霜、淡粉色的叶子、花序的程度和花朵的形色都可以看出区别。
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拓跋莲与朱丽安娜的异同。其实差异挺明显的，故略过不译。 |
Echeveria juliana is known only from the type locality in tropical deciduous forest at 359 m (1080ft) altitude, whereas its recently rediscovered closest relative, E. tobarensis, grows at more than 2020 m (6630 ft) in pine forests (Etter & Kristen 2011). Unlike E. tobarensis, E. juliana does not tolerate low temperatures in cultivation. There are only a few echeverias known so far that grow below 1500 m (4920 ft) in the mountains of the Pacific slope: E. pallida Walther at 140 m (460 ft), E. laui Moran & Meyrán at 550 m (1800 ft), and E. acutifolia Lindley usually between 200 and 1000 m (660–3280 ft). Most of the Echeveria species are therefore found in temperate zones. E. juliana is the only species known so far in northwestern Mexico growing below 400 m (1310 ft).
就目前所知，E. juliana只在模式标本产地栖息，那是一个海拔359米的热带落叶林，而它的近亲拓跋莲却生长在海拔2020米以上的针叶林中。不像拓跋莲，juliana无法忍受低温。截至目前，已知的拟石莲中只有为数不多的几种生长在海拔1500米以下面向太平洋的山坡，他们是霜之鹤（140米）、雪莲（550米）和E. acutifolia（通常200-1000米之间）。大部分拟石莲属植物其实都生长在温带环境下。E. juliana实际上是唯一已知长在墨西哥西北部海拔400米以下的物种。
The changes in geomorphology and morphoclimate are the result of various volcanic activities, products of long and intense geologic activity during the Cretaceous and Cenozoic periods. These changes caused geographic and genetic isolation in many populations of species of the Crassulaceae family. This can be seen in the richness and the endemism of different species of the Sierra Madre Occidental such as Sedum lumholtzii Robinson & Fernald, S. bellum Rose ex Praeger, S. kristenii Reyes, González-Zorzano & Etter, S. spathulisepalum Clausen, S. trichromum Clausen, S. craigii Clausen, Villadia pringlei Rose, Graptopetalum filiferum (Watson) Whitehead, G. bellum (Moran & Meyrán) D.R. Hunt, among others. This region, one of the largest zones of igneous-silicate origins in the world, covers an area of 289,000 square kilometers with altitudes varying from 200 m to up to 3000 m (Ferrusquía 1998).
这种地理分布和形态方面的差异性是火山活动造成的，剧烈的地质变化导致景天科个物种间出现了地理隔离，进而演化出了不同的基因。Madre Occidental山脉那特有的丰富物种无疑是这一观点的最佳佐证。
ACKNOWLEDGMENTS
The authors thank Myron Kimnach for valuable comments and additional data that have improved the manuscript. They also thank Pablo Carrillo Reyes for revising the manuscript and for his thoughtful suggestions helping to improve this article. Our appreciation also goes to Enriqueta Molina of SINAREFI/SAGARPA for his support of the project “Red de Echeveria” in agreement with the Instituto de Biología de la Universidad Nacional Autónoma de México, and to SEMARNAT for the official federal collecting permit SEMARNAT SGPA/DGVS/02315/10.
各种致谢。
LITERATURE CITED
Etter J, Kristen M. 2011. The rediscovery of the elusive Echeveria tobarensis. Cact. Succ. J. (US) 83: 275–283.
Ferrusquía VI. 1998. Geología de México: una sinopsis.
In: Ramamoorthy TP, Bye R, Lot A. Diversidad biológica de México: orígenes y distribución. Universidad
Nacional Autónoma de México. México. Pp. 3−108.
各种引用。
原文下载：http://www.crassulaceae.ch/index.php?TPL=113&x270_id=2988&x270_listsearch=1
