A trip on the Ruta 5 in

Argentina, along the

bolivian border

Thomas Guerry

© March 2020

There is a huge diversity

of cacti in Argentina, and

many areas allow

travellers to contemplate

a wide variety of species

in a few days only.

The province of Jujuy is

one of them, and in

particular the Ruta 5

along the bolivian

border, around the city

of La Quiaca which is

one of the main crossing

points between

Argentina and Bolivia.

While going up to the

north along the Ruta 9,

connecting Buenos Aires

to the bolivian border,

one can come across

many species of dwarf

Opuntias near the city of

La Quiaca.

One of them is

Tephrocactus nigrispinus,

one of the smallest

species of the genus

Tephrocactus.

This species makes small

clusters of around 20

centimeters in diameter,

and makes bright red

flowers, and fruits of the

same color.

The landscape seems

barren, but this is only a

feeling…

Another very common

species in the province of

Jujuy is Maihueniopsis

molfinoi, also called

M. hypogaea or M.

glomerata ssp

hypogaea.

With M. camachoi and

M. conoidea in Chile, this

is one of the

northernmost species of

Maihueniopsis.

Most plants have spines

with a white basis and a

dark tip, only located at

the uppermost areolas of

the segments, but a few

plants have no spines at

all, only glochids.

But a few species are far

more difficult to spot,

because they are much

more discreet and

growing in specific

environments.

This is the case of

Cumulopuntia

subterranea (formerly

Puna subterranea),

whose segments do not

exceed the ground level

from one or two

centimeters.

During the dry season,

this plant is very difficult

to spot in this very arid

landscape, however they

are here !

There is another

Cumulopuntia in this

area, which is probably

closely related to

Cumulopuntia boliviana,

making bigger clusters

than C. subterranea, but

smaller than the ones of

the typical form of C.

boliviana.

Once arrived in La

Quiaca, we turned to the

east, along the bolivian

border, until arriving to a

place that some call

« the Oreocereus forest ».

Many species of cacti

grow in this place, but

the first ones that we can

see, because of their size

and density, are

Oreocereus.

Two species grow there :

O. celsianus and O. trollii.

Oreocereus celsianus are

plants with eretec stems,

up to two meters high.

Flowers are long and

narrow, therefore they

are adapted to be

fecundated by

hummingbirds. When

mature, the fruits are

bright yellow and contain

several hundred of seeds

each.

Oreocereus trollii are

smaller plants, with

crawling stems instead of

erected ones, and with

colorful spines visible

through the layer of silks,

similar to hairs, typical

from th genus

Oreocereus.

Smaller but nevertheless

easily visible, Lobivia

ferox is a globular cactus

making big flowers,

which are most of the

time white.

In rare cases, hybrids of

Oreocereus celsianus

and Lobivia ferox are

created by the

fecundation thanks to

insects.

Those plants are smaller

than Oreocereus

celsianus, with spines and

a green epidermis

inherited from Lobivia

ferox.

Another omnipresent

species along the slopes

of the hills coverd by

Oreocereus is

Cumulopuntia boliviana,

with particularly big

segments and strong

spines.

There are two other

species in this place, that

are growing on the top of

the hills and not on the

slopes.

The first is Rebutia

pygmaea, making very

small heads barely

exceeding 1 centimeter

in height and diameter.

Two varieties of Rebutia

pygmaea grow there,

one with orange/salmon

flowers, the other with

pink flowers.

Excepted during

flowering time, it is

extremely difficult to spot

these tiny heads on the

ground.

The other plant, difficult

to find because hardly

exceeding the ground, is

Neowerdermannia

vorwerkii.

After leaving the

Oreocereus forest and

going to the west of La

Quiaca, we spotted

some eye-catching

patches of colour along

the road.

This was a wonderful field

of flowering Lobiva ferox,

and all of these flowers

had different colours,

which is quite surprising

for this species.

A little further on the

road, one can find some

other species typical

from this area.

Among them, Parodia

maassii is a superb

species of the genus

Parodia, with long gold

hooked spines.

This species makes

beautiful dark orange

flowers.

There are few Austrocylindropuntia species in Argentina,

but there is in this area Austrocylindropuntia shaferi, that

makes long stems with pink to red flowers, and fruits

containing a few big seeds only.

There are again a few

plants of

Neowerdermannia

vorwerkii, but this time

hidden under bushes.

A few Rebutia are

hidden under the bushes

as well, but without

flowers they are difficult

to identify !

There are many forms of

Tunilla in north-west

Argentina, to such extent

that it is very difficult to

distinguish different

species.

This one is one of the

most common ones, and

is probably close to

Tunilla soherensii.

But the treasure growing

in this north-west end of

Argentina is the tiny and

rare Yavia cryptocarpa.

This species, very

appreciated by cacti

lovers, is endangered

because of its scarcity

and of the lootings that

happened on some

localities.

This plant grow in cracks,

and is only

distinguishable by its

round shape in the

middle of the sharp-

edged stones.

The biggest plants are

only 3 centimeters in

diameter.

Five Yavia are hidden on

this picture, it is your turn

to find them !

At the far end of the Ruta

5, before turning to the

south, the northernmost

village of Argentina

stands there : Santa

Catalina.

Slightly over 300

inhabitants live there, at

around 3800 meters in

altitude.

Santa Catalina is the

type locality of

Maihueniopsis molfinoi,

that we have already

seen previously.

Surprisingly, the fruits, that

are small and red when

ripe usually, are here a

little bigger and rather

yellowish, with only a

reddish end.

There is also an atypical

Cumulopuntia, with fine

black spines. This is

probably one of the

numerous forms of

Cumulopuntia boliviana.

The road along the

bolivian border ends

here, with these few

flamingos.