Machado&Charles2004

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ust occasionally, a truly individual new cactus species

is discovered. A recent example is P. bohlei whichwas described in 2001 in KuaS, the journal of the

German Cactus and Succulent Society (Hofacker

2001). It was discovered in 2000 in the northern part

of the state of Bahia in Brazil, during a field trip

undertaken by Andreas Hofacker, Graham Charles,

Konrad Herm and Bernhard Bohle. The trip was led

by Kurt Ingo Horst, son of the eminent cactus explor-

er, Leopoldo Horst. The species was found near the

small hamlet of Minas do Mimoso growing on a hill-

side which differed from the surrounding woodland

because of its white sandstone rocks and quartz sand.

A few kilometres away is the type locality of

Discocactus zehntneri subsp. horstiorum (P.J.Braun)

P.J.Braun & Esteves Pereira, another little known plant

from the eastern part of the Serra So Francisco. The

habitat is composed of outcrops of white sandstone

rock with the plants of P. bohleigrowing in the white

quartz sand in between. Other cactus species found at

the habitat are Micranthocereus flaviflorus Buining &

Brederoo, Pilosocereus pachycladus F.Ritter, Melocactus

zehntneri(Britton & Rose) Ltzelburg, Leocereus bahiensis

Britton & Rose, Tacinga inamoena (Schumann)

N.P.Taylor & Stuppy and Cereus albicaulis (Britton &

Rose) Ltzelburg.

P. bohlei grows to just over two metres in height,branches from the base and has a bluish epidermis,characteristics often seen in other Brazilian species ofthe genus Pilosocereus. However, there are a number ofcharacters which make this new species remarkable.Firstly, it possesses dimorphic stems, that is, it has dif-ferent morphologies in the juvenile and mature por-

tions of the stem. In the juvenile phase the stem is

thick and club-shaped, with a straight valley betweenthe ribs, the close-set areoles bearing short spines.Then, when the stem reaches a certain size, it changesits morphology, becoming mature and capable of flow-ering. The stem tapers and becomes thinner, whilst theribs become shallower with a wavy valley between,and transverse folds develop above the areoles. Thespination grows longer and stronger, and the floweringareoles develop tuffs of long silky hairs which encirclethe flower buds. On older stems the epidermis devel-ops paler patches of light grey-green.

This dimorphism between juvenile and mature portionsof the stem with the swollen stem bases and narrowerfertile apex confers to P. bohleia bottle-shape which isreminiscent of the bottle-cactus, Stephanocereus luetzel-burgii(Vaupel) N.P.Taylor & Eggli. The morphology ofthe mature portion of the stem with its wavy valleysbetween the ribs and tuffs of wool are also very sim-ilar to the stem morphology of Pilosocereus gounellei(F.A.C.Weber) Byles & Rowley. In the originaldescription of P. bohlei it is compared to bothP. gounelleiand S. luetzelburgii which in the article isconsidered to be a species of Pilosocereus: P. luetzelburgii(Vaupel) Byles & Rowley. P. bohlei is regarded byHofacker as a link between the subgenera Gounellea

Zappi (to which P. gounellei belongs) and Lagenopsis(F.Buxbaum) P.J.Braun (to which P. luetzelburgiibelongs). Opinions vary about the correct placementof S. luetzelburgii; the opinion of the authors is that thistaxon is not closely related to either Pilosocereus orStephanocereus, and should instead be in a genus of its

Pilosocereus bohleiHofacker

a remarkable new species

from BrazilMarlon Machado1 and Graham Charles2 discuss a recently described new species of

Pilosocereus from Bahia in Brazil. Photography by the authors.

1Departamento de Cincias Biolgicas, Universidade Estadual de Feira de Santana, Rodovia BR 116, km 03,

Feira de Santana, Bahia, CEP 44031-460, Brazil. Email: [email protected]

2Briars Bank, Fosters Bridge, Ketton, Stamford, PE9 3UU, England. Email: [email protected]

Figure 1 (facing page) A view of part of the extensive new

habitat near Delfino, Bahia, Brazil

PiloBohlei.qxd 02/02/2005 23:48 Page 1


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own. The similarity between P. bohlei and S. luetzel-burgii relies solely on the dimorphic stems that bothspecies develop; this is, however, likely to be an exam-ple of convergence and not indicative of a close relat-ionship.

In spite of the similar stem morphology of P. bohleiand P. gounellei, the first does not have subapicallybranching stems a diagnostic feature of subgenusGounellea, which confers to the species in this subgenusa typical candelabra shape. The other diagnostic feat-ure of subgenus Gounellea is the fruit morphologywhere floral remnants are frequently erect and notsunken into the apex of the pericarp. The situationcould not be verified for P. bohleibecause at the time ofits discovery the plants were not in fruit and thus adescription of the fruit was not provided in the orig-inal description. Taylor (2004), however, reports thatHofacker has more recently described the perianth

remains as deeply inserted so ruling out a close rela-tionship with subgenus Gounellea. A conclusion whichTaylor says is supported by the flower which is shortand S-shaped, suggesting a relationship with theAurisetus Group of Pilosocereus.

For some time P. bohleiwas known only from its typelocality and another small place nearby, the type local-ity of a form of Discocactus zehntneri subsp. boomianus(Buining & Brederoo) N.P.Taylor & Zappi which wasdescribed as Discocactus araneispinus. Although P. bohleiwas seen by Bnecker, Buining and Heimen at thislocality, none of them realized that it was an unde-

scribed species.In March of 2004 the first author found a second,much larger population near the small town ofDelfino, a few tens of kilometres from the originalfinding place. At this second habitat the plants growin an environment similar to the type locality, fields ofwhite quartz sand amongst outcrops of white sand-stone rock. The new population consists of thousandsof plants, and the habitat is much more extensive thanthe original. This was a completely chance finding,since the botanical expedition at the time had theobjective of finding new populations of a species of

everlasting flower, Syngonanthus curralensis Moldenke(Eriocaulaceae). Other cactus species found growing atthe new habitat are Micranthocereus flaviflorus,Pilosocereus pachycladus,Melocactus paucispinusG.Heimen& R.Paul, M. concinnus Buining & Brederoo, andTacinga inamoena (Schumann) N.P.Taylor & Stuppy.

This habitat also represents a northern extension to thegeographic range of M. paucispinus; a species whichwas first discovered near the town of Seabra in thecentral region of Bahia, then more to the south nearthe towns of Rio de Contas and Abara, and later stillby the first author further north near the town of

Morro do Chapu (Machado 1999).

Some plants of P. bohleibore near ripe fruits at the timeof the discovery of the second habitat, and cutting afruit in half showed that it had the typical morphologyof subgenus Pilosocereus, with floral remnants sunkeninto the apex of the pericarp, thus supporting theobservation of Hofacker and interpretation of Taylor.The similar stem morphology of P. bohlei andP. gounelleiis most likely to be another example of con-vergence and not indicative of a close relationship.

Another remarkable feature of P. bohleicame to light

when a plant was dug up in order to prepare a herbar-ium specimen; it had a number of large root tubers! No

Figure 2 (facing page)

A mature plant ofPilosocereus bohlei at the new habitatFigure 3 A young plant ofP. bohlei showing an example

of its root tubers



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other Pilosocereusspecies is known to develop tuberousroots, a feature rarely found in Brazilian Cactaceae.Similar underground storage organs can be seen inCereus subgenus Mirabella (F.Ritter) N.P.Taylor [Cereusalbicaulis (Britton & Rose) Ltzelburg and CereusmirabellaN.P.Taylor]; Cipocereus crassisepalus(Buining &Brederoo) Zappi & N.P.Taylor; Discocactus bahiensis

Britton & Rose and Arrojadoa eriocaulis Buining &Brederoo and perhaps forms of A. dinae Buining &Brederoo (although in the Arrojadoaspecies the tubersare in fact swollen subterranean stems, not roots).None of these species belongs to genera closely relat-ed to Pilosocereus.

During a second visit to the Delfino population, thetwo authors together with Chris Pugh and Ivor Crookin July of 2004, observed the final remarkable feature.The plants were again found in fruit and it wasobserved that the ripe fruits do not split open in thesame manner all the other Pilosocereus species, but

instead they fall to the ground intact, with a basalopening at the point of attachment of the fruit to thestem. This feature is only known from Stephanocereusleucostele(Grke) A.Berger, whose fruits exhibit similarbehaviour, but which is a completely unrelated species.

P. bohleiis indeed a unique, remarkable new species. Ithas features not found in any other Pilosocereus, and

similarities with a number of species from other gen-era not close to Pilosocereus. It may be related toP. machrisii (E.Y.Dawson) Backeberg considering thesimilar morphology of the juvenile stems, the flowershape, and to the habit of branching from the base, butat the moment there is little available information to

reach any conclusions about the true affinities ofP. bohlei. It is certainly a species that deserves morestudy.

Readers will have the chance to cultivate this beautifulplant when the BCSS offers seeds of this and otherdesirable Brazilian species in a special distribution tobe announced in the March 2005 journal.

ACKNOWLEDGEMENTS:The authors would like to thank Bernhard Bohle for his assistance incompiling this article

REFERENCES:HOFACKER, A. (2001). Pilosocereus bohlei Hofacker spec. nov. eine

neue Art aus Bahia. Kakt. u. a. Sukk. 52(10): 253-257.MACHADO, M. (1999). The cacti of Morro do Chapu, Bahia, Brazil.

Brit. Cact. Succ. J. 17(4): 201-213.TAYLOR, N.P. & ZAPPI, D.C. (2004) The Cacti of Eastern Brazil. RBG,

Kew.ZAPPI, D.C. (1994) Pilosocereus (Cactaceae) The genus in Brazil. Succulent

Plant Research Vol.3.Figure 4 P. bohlei with developing fruit

Figure 4 P. bohlei with developing flower bud


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