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A new cliff dwelling species of Espostoa Br. & R.(Cactaceae) from northern Peru Paul Hoxey 34 Stonehill Road, Great Shelford, Cambridge CB22 5JL, England (email:
[email protected]) Summary: Espostoa cremnophila is described as a new species of cactus from Peru. It grows exclusively on vertical cliff faces in a side valley of the Río Marañón in the northern part of the Department of La Libertad, Peru. It is likely that the most closely related taxa are Espostoa calva F. Ritter and Espostoa utcubambensis G.J.Charles with which it is compared.
Zusammenfassung: Espostoa cremnophila wird als neue Art aus Peru beschrieben. Sie wächst ausschleisslich an vertikalen Felsklippenflächen in einem Seitental des Río Marañón im nördlichen Teil des Departments La Libertad, Peru. Es scheint wahrscheinlich, dass Espostoa calva F. Ritter and Espostoa utcubambensis G.J.Charles die am nächsten verwandten Arten sind, und mit diesen wird sie verglichen.
Photographs by the author except where stated
Introduction In November 2013 Graham Charles, Chris Pugh and myself undertook a three week expedition to Peru visiting the Departments of Cajamarca, La Libertad and Ancash in the northern part of the country. We paid particular attention to the Río Marañón and its tributaries. The terrain is especially rugged with deep valleys surrounded by high Andean mountains which help to isolate populations and allow speciation to occur. Within the valleys a warm and arid micro climate has allowed an extensive cactus flora to develop. The German cactus explorer Friedrich Ritter, during his South American explorations in the 1950's and 60's, did more than anyone else to study the cacti of this region and he described many new species of cacti. More recently, as the region has becomes increasingly accessible due to
Figure 1. E. cremnophila showing the bent cephalium bearing stems. Photograph: Graham Charles
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Figure 3. E. cremnophila. Section of the flower from the type specimen.
Figure 2. E. cremnophila. The type specimen flowering prior to preservation.
the improvements in the road network, additions to the Marañón flora have been published including Borzicactus hutchisonii, Espostoa utcubambensis, Matucana rebutiiflora and Matucana hoxeyi, all plants endemic to valleys within the drainage basin of the Río Marañón. A rather fortuitous set of circumstances allows me to introduce another new species. We planned to visit a hill called Carrizal, a place visited by Lau and described by him in the NCSS journal (Lau 1972). It is an important historical cactus locality because it is the type location of two matucana species; M. weberbaueri and M myriacantha; discovered by August Weberbauer and described by Friedrich Vaupel near 100 years ago. However, the road that climbs up from Balsas on the eastern side of the Río Marañón was blocked by a digger preparing a trench to lay a drainage pipe under the road. We were told by the workers that the road would be closed all the next day but would open again the day after. That left us with a spare day in our itinerary. That night we stayed in the village of San Vicente south of the Río Marañón river crossing at Balsas so we decided to explore in the vicinity. The next day we planned to visit the nearby village of Chuquibamba and with directions from
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Figure 4. E. cremnophila. Stem cross section of the type specimen prior to preservation.
the proprietor of the hotel attempted to find it. However, after crossing a small bridge on the outskirts of San Vicente, we failed to take the correct track and started to follow a road up a side valley away from the Río Marañón. We encountered a few Espostoa lanata growing on well vegetated slopes with small trees and bushes but little else until we encountered vertical conglomerate cliffs above the river near the village of San Francisco. The cliffs were home to a species of Espostoa with a distinctive bent stem and a downward-facing cephalium, somewhat reminiscent of Espostoa (Thrixanthocereus) senilis when observed from a distance. We could not immediately identify the plant but it was clearly an espostoa with a true lateral cephalium. The espostoa occurred on several more cliff faces, scattered throughout the valley always with a very consistent appearance. We dedicated the rest of the day to trying to study the plant, a far from easy task due to the inaccessibility of the habitat. With difficulty we approached three or four plants and we managed to examine one specimen in detail and decided it was a new species. I compare it here with Espostoa calva and Espostoa utcubambensis which are likely to be the closest relatives.
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Figure 5. E. cremnophila growing on steep cliffs in the valley of the Rio Chivane, La Libertad, Peru Espostoa cremnophila P. Hoxey spec. nov.
Diagnosis Cliff dwelling espostoa compared with and presumed related to Espostoa calva F. Ritter and Espostoa utcubambensis G.J.Charles but with white hairs and thin flexible yellow coloured spination. Cephalium of dense hairs, mainly brown but some white. Wide, covering nearly half the stem, but short, rarely exceeding 50cm in length. Often on a sloping stem section facing downwards. Flower small, cream coloured and nocturnal with a musty odour, presumably pollinated by bats.
Type Peru, Depto. La Libertad, valley of the Río Chivane, east of San Vicente, between San Francisco and Uchumarca, on the road to Bolivar; 2390m; Hoxey (PH)1045.01; collected on the 10th November 2013 by Paul Hoxey, Graham Charles and Chris Pugh (Holotype HUSA, Herbarium Arequipense)
Etymology The epithet 'cremnophila' derives from the Greek 'kremnos” for cliff and “-philus” for friend. This alludes to the exclusive cliff dwelling habitat preference of this taxon.
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Description Habit: Tree-like to 5m tall, branching from a woody trunk 1–1.5m high. Fastigiate with 5–15, sometimes less, vertical growing and parallel branches. Stems: 70mm in diameter, epidermis greygreen and slightly glossy. Ribs: About 20, 8–10mm across and 8mm high. Hemispherical rounded shape with v-shaped notch above the areole. Areoles: 4mm in diameter, reddish-brown felt when young (a similar colour to the cephalium wool) fading to grey later. 9–10mm spacing midpoint to midpoint of areoles. Spination: Central spines; 1, rarely 2, thin straight, flexible, yellow to 15mm long, occasionally to 20mm. Radial spines about 20, light yellow through to white or light grey, thin straight, flexible to 5mm long, radiating equally Hairs: Persistent white hairs to 20mm in length. Densest on young seedlings or at the apex on mature plants. Cephalium: rarely exceeding 50cm in length. Composed of dense hairs to 15mm long, predominately brown with some white. Covering approximately 10 ribs and nearly the full stem diameter. In age the cephalium causes the host stem to bend over from the vertical by up to 45 degrees, sometimes a little more, leaving the cephalium facing in a downwards direction.
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Features Body Stems Epidermis Ribs
Espostoa calva F. Ritter
Espostoa utcubambensis G. Charles
Espostoa cremnophila P. Hoxey
Parallel, vertical 3–6m long 60–90mm in diam.
Closely spaced, erect 90mm in diam.
Vertical and closely spaced 70mm in diam. Prominently curved towards the cephalium
19–23, 5–7mm high
25–30, 7mm across and 5mm high
20, rounded, 8–10mm across and 8mm high
4–9m tall
Glossy, bright green
5–7m tall
Dull matt grey-green
to 5m tall
Grey-green
Dark reddish brown felt felt 2mm diam. 2–2.5mm in diam. 4–5mm White 8–9mm apart apart
Reddish brown felt 4mm diam. 9–10mm apart
Radial spines
Central and radial spines not well differentiated 11–12 short to 5mm long 12–18, golden yellow, nee- red-brown becoming dle-shaped, 4–8(–15)mm whitish long
About 20, light yellow through to white or light grey, thin straight, flexible, to 5mm long
Areole Hair
Completely absent
A little on new areoles at the apex
Cephalium
To 2–3m long tufty yellowish wool, covering 6–8 ribs
Greater than 1m long dark Dense brown hairs, grey wool, covering 8 to 12 covering about 10 ribs up ribs up to 70mm across to 70mm across
Red?/White? *
White
Unknown
Valley of the Río Utcubamba, Dept. Amazonas, Peru
Valley of the Río Chivane, east of San Vicente. Dept. La Libertad, Peru
Steep rocky hills or cliffs, among trees.
Steep conglomerate or grey limestone cliffs.
Areoles
Sporadic but when 1(–2), thin straight, flexipresent 2(–6) initially red- ble, yellow to 15 brown becoming whitish, to (–20)mm long 20mm(–40mm) long
Central Spines
35mm diameter and 52mm 30mm diameter 40mm long creamy-white musty long, creamy-white musty smell smell
Flower
40mm diameter, creamywhite
Seed
Oval, 1.9 x 1.1 mm, glossy, black-brown
Oval, 1.8 x 1.1mm, glossy, black-brown
1800 to 2400m
1350 to 1950m
Fruit
Location Altitude Range Habitat
Valley of the Río Marañón, east of Balsas, Dept. Amazonas, Peru Growing on steep slopes among trees as a forest emergent.
Persistent white hairs, especially on seedlings and at the apex of mature stems
Unknown
2100 to 2800m
Table 1. A comparison of characters between Espostoa calva, E. utcubambensis & E. cremnophila * Ritter reports the fruit of Espostoa calva to be red but mature fruits found on the plants in January 2000 were white [see Figure 7 in Charles & Woodgyer (2003)].
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Jaén
Bagua
6°S
Moyobamba Chachapoyas
Bambamarca Chiclayo
Leimebamba Balsas Celendín
7°S Cajamarca 79°W
Bolívar 78°W
78°W
Map 1 Geographic distribution of Espostoa cremnophila (green dots), Espostoa calva (red dots) and EsM postoa utcubambensis (yellow dots) in northern Peru. Departmental boundaries (black lines) and some Departmental boundaries (black place names are included. l
Flowers: nocturnal, emerging from the cephalium and opening at dusk. Creamy-white with a musty smell. 40mm long and 30mm across. The flower tube is 3mm thick, naked with small pale pink scales, progressively increasing in size from the bottom to the top. Outer perianth segments creamy coloured with a pale pink tip, 10mm long by 3mm wide. Inner perianth segments creamywhite, and slightly larger; 12mm long and 5mm wide. Stigma 30mm long with 2mm long stigma lobes. Nectar-chamber 10mm long and 6mm wide. Ovary 3mm long and 4mm wide. Stamens very numerous, white about 20mm long, pollen very pale yellow. As with all espostoa species most likely pollinated by bats (chiropterophily). Fruit and seeds: unknown Habitat & Distribution: Growing exclusively on vertical cliff faces of either a light coloured and easily eroded conglomerate rock or a hard grey limestone. Only known from the river valley of the Río Chivane, east of San Vicente in the northern -most part of the department of La Libertad close to the border with the department of Amazonas. An extensive survey has not been conducted but Espostoa cremnophila grows in an altitude range from 2100m to 2800m along approximately 10 to 12km of the valley.
Figure 6. Espostoa cremnophila whole plant
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Associated vegetation The vertical habitats are only lightly vegetated but are home to several Bromeliad species. Except
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Figure 7. Espostoa utcubambensis GC1063.02 in the Rio Utcubamba Valley, Amazonas, Peru. Photograph: G. Charles
Figure 8. Espostoa utcubambensis GC1063.02 in the Rio Utcubamba Valley, Amazonas, Peru. Photograph: G. Charles
Figure 9. Espostoa calva GC609.01 below Chanchillo, Amazonas, Peru. Photograph: G. Charles
Figure10. Espostoa calva PH207.01 below Chanchillo, Amazonas, Peru.
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Figure 11. Comparison of stems and spination of Espostoa calva PH207.01 (left), Espostoa utcubambensis PH206.01 (centre) and Espostoa cremnophila PH1045.01 (right)
for a small population of Matucana haynei ssp. myriacantha we failed to find any other cacti growing in close association with Espostoa cremnophila. Lower down the valley, below an altitude of approximately 2000m, Espostoa lanata grows in small numbers on well vegetated slopes and rocky places.
Conservation status Espostoa cremnophila has a specialised ecological niche and a small range which restricts the number of possible places it can inhabit. Even suitable habitats are not densely populated, so the plants are not numerous. However, the population appears stable and reproducing. It is not in danger on inaccessible cliffs that are totally unsuitable for agriculture and hence unaffected by man's activities. An IUCN Red List conservation rating of Vulnerable (VU – Criterion D2) is appropriate due to the restricted area of occupancy and relatively small population.
Discussion The obvious taxa to compare with Espostoa cremnophila are E. calva and E. utcubambensis. Espostoa calva grows approximately 20km away further downstream in the Río Marañón valley, in a small restricted range on the east side of the river. Espostoa utcubambensis grows a little further afield in the Río Utcubamba where it is widespread and common. It is isolated from Espostoa
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cremnophila by a high mountain range but nevertheless is only about 80km distant. It is remarkable that all three large growing cereoid species have only been recently described. Espostoa calva, the earliest to be named in 1981 (Ritter 1981) and Espostoa utcubambensis in 2003 (Charles & Woodgyer 2003) although the latter was collected back in the 1950's by the American botanist Paul Hutchison. Espostoa lanata, a widespread species in northern Peru, is not considered closely related because it grows in quite close association with both Espostoa calva and Espostoa cremnophila. Espostoa lanata also has a much larger flower (40–80mm compared to 40mm maximum for the other three species) and much more significant areole hair. Table 1 is adapted and extended from the one published by Charles & Woodgyer (2003) and compares characters of the three taxa. Data for Espostoa calva and Espostoa utcubambensis are from the original descriptions and expanded by personal observations in habitat and from seed raised plants in cultivation. Espostoa cremnophila shares features with both E. calva and E. utcubambensis but can be distinguished from both quite easily. It is rather less likely to branch than the other two species and perhaps most distinctively, at least from a distance, is the relatively short but wide cephalium that tends to face downwards on sloping stems.
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Figure 12. Seedling of Espostoa cremnophila showing the areole hair.
Close up, the stems of Espostoa cremnophila have similar spination to E. calva but it is less intensely yellow. The areoles are also less deep reddish brown but the most obvious difference is the persistent white hairs of Espostoa cremnophila which are always absent in E. calva. Espostoa utcubambensis is equally distinct and with a dull mat grey-green epidermis that immediately differentiates it from all other taxa in the genus. The spination is also distinct with short radials and sporadic and randomly emerging central spines. It has a little hair towards the apex but it is never as extensive as that found on Espostoa cremnophila. However it is more like Espostoa cremnophila in its habitat preference, favouring steep rocky habitats. All three species have restricted distributions, geographically close yet isolated sufficiently to prevent gene interchange. Perhaps they are isolated relics of a once more widespread taxon.
Acknowledgements I thank Graham Charles and Chris Pugh for being wonderful travelling companions and for help and support in writing this article. Thanks also go to Fátima Cáceres at the Universidad Nacional de San Agustín de Arequipa for accepting the type specimen.
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Figure 13. Espostoa lanata PH1045B.01 near the Río Chivane, La Libertad, Peru at 1770m
References CHARLES, G., & WOODGYER, E. (2003). A new species of Espostoa from Peru. Brit. Cact. Succ. J., 21(2): 69–74. HUNT, D.R., TAYLOR, N.P., & CHARLES, G. (2006). The New Cactus Lexicon. dh books. LAU, A. (1972). In Search of Cacti. Nat. Cact. & Succ. J. 27(2):43–46 RITTER, F. (1981). Kakteen in Südamerika: Band 4. Peru. Spangenberg, Friedrich Ritter Selbstverlag: 1239–1692.
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