Horticultural Wednesday I

Phalaenopsis is a very popular orchid genus originating from southeast Asia, with several horticultural varieties. The fine specimen above was photographed in Puerto de la Cruz, in Tenerife.

Death of a Phoenix

Palms are a common sight in Malta, with the warm temperatures affecting the islands throughout most of the year being a perfect catalyst for their growth and proliferation. This said, indigenous species amount to just one - the low-growing, bushy Chamaerops humilis L., now practically extinct in the wild.

Chamaerops humilis L., photographed by Aron Tanti

The recent invasion of the red palm weevil Rhynchophorus ferrugineus (Olivier, 1790) has affected several of the ornamental palms of the genus Phoenix.

Rhynchophorus ferrugineus (Olivier, 1790) from www.cm-oaz.pt

 
The date palm, Phoenix dactylifera L., is a historically important North African species that may be distinguished by leaves arranged in wide silvery fronds. The picture beneath shows this species of palm affected by the Rhynchophorus beetle.

Phoenix dactylifera L. affected by the red palm weevil in Santa Venera, Malta

Phoenix sp. in Rome, Italy, with the one on the right showing symptoms of red palm weevil infestation

Phoenix canariensis Chabaud is a Canarian endemic which is frequently planted around the Mediterranean, not least in Malta. Unfortunately it is also affected by the weevil in question and several stately specimens from around the island have been destroyed.

Phoenix canariensis Chabaud in the main road of Floriana, Malta

The inhabitants of Tenerife certainly make excellent use of their endemic palm species!

Phillumenic conundrum

Prior to this event I had never heard of the obscure hobby of phillumeny, but what should have been a casual glance inside an antiques shop in Santa Cruz necessitated some brushing up on the matter. I could not resist leaving this singular item to gather dust on a shelf unless that shelf was mine.

this is all I know about this set

A defunct (?) match factory in Las Palmas (capital city of Gran Canaria), Fosforera Canariense, produced this nice set of 24 matchboxes sometime last century after its foundation in 1935. Information regarding such items is hard to come by, on-and-offline, therefore not much more is known at this stage.

click on image for large version

The set is called Caracolas Marinas (marine snails) and features 24 species of molluscs (inexplicably consisting of one bivalve and 23 predominantly tropical, not-all-marine, gastropods) heavily inked onto a pale blue background. The way they are packaged makes it impossible to see what is on the hidden side of each matchbox, and where, presumably, the species identifications are printed.

click on image for large version

Now, I am sorely tempted to tear open the polythene covering holding the set together in order to read them; on the other hand, doing so will detract from the neatness and value of the boxed set. I'm a stickler for 'accurate' identification (as opposed to mere Cypraea, Murex, Lambis, Harpa, Conus, Architectonica, Mitra, Cymatium etc.) but these cardboard versions will have to remain a mystery, at least until curiosity gets the upper hand.

In trouble

Butterfly pupa, with parasitic wasps. Aguamansa, Tenerife 2011.

Flowers on the volcano

Following yesterday's journey we have now arrived close to the summit of El Teide. The landscape is a vast expanse of bleak volcanic rock, including obsidian, phonolite and trachyte, which form when lava solidifies according to different physico-chemical criteria.

El Teide volcano

Teide's most recent eruption dates back to 1909, and some tremors have been recorded in 2004, indicating a dormant volcano may become active in a few years' time.

El Teide's 1909 eruption, live (photo stolen from here)

In any case, the plants seem quite happy about their choice of habitat. A large number of endemic species characterize Tenerife and many of these species are abundant high above the pine forest. The southern side of the Teide, in the Las Cañadas caldera, is a habitat known as subalpine scrub, dominated by shrubs of the legume Spartocystus supranubius L., together with bushes of the beautiful Pterocephalus lasiospermum Link.

dark green shrubs of Spartocystus supranubius L., with Pterocephalus lasiospermus Link in the foreground

Spartocystus supranubius L. with seed-pods

Pterocephalus lasiospermus Link

flowers of Pterocephalus lasiospermus Link

Amongst these one can also find the very interesting Cheirolophus teydis (C.Sm.) G.López, an endemic plant of Teide that is a very close relation of Malta's national (and also endemic) plant, Cheirolophus crassifolius (Bertoloni). Unfortunately all plants were only on the verge of flowering during this visit. Flowers of C. teydis are pale yellowish.

Cheirolophus teydis (C.Sm.) G.López

Adenocarpus viscosus (Willd.) Webb & Berthel. and several species of Echium are also very characteristic inhabitants of El Teide, characterizing landscapes with their yellow flowers and tall spikes respectively.

Adenocarpus viscosus (Willd.) Webb & Berthel.

Echium sp.

Echium sp. flowers

lycaenid butterfly resting on Echium sp.

Above the clouds of El Teide

The third largest volcano on earth (according to some sources, but not to others - it depends on how you go about measuring volcanoes) is found off West Africa, on Tenerife.

To see the majestic peak of this volcano, El Teide, one must traverse a height of about two kilometres of pine forest, dominated by the endemic Canarian pine Pinus canariensis C.Sm. This pine has developed an extraordinary way of utilizing the water available in the mist enveloping these forests - its leaves are tall and thin, allowing condensation of water droplets on their large surface area. This water trickles down, dropping into the soil and providing roots with much-needed hydration.

Pinus canariensis C.Sm., 2.5km up east El Teide

In some places, violent storms some years back have ripped the trees down, the trunks of which together with the flowing clouds produce an eerie atmosphere reminiscent of any horror film worth its salt:

wind-battered pine forest, c. 2km up east El Teide

After the ascent of about another kilometre one can see the forest spread below and a wide swathe of cloud enveloping it:

About 3km up El Teide, the volcano in the background

Coming up next: some local flora.

My first encounter with a Canarian dinosaur

As soon as one starts travelling around Tenerife one starts becoming aware of a particular species of reptile populating much of its landscapes. The first things that struck me about this animal are its fairly large size (about 30cm in males) and its bold colouration, which are features by all means not unheard of in lizards (see here for an extinct Maltese giant lizard); however, being more accustomed to the smaller and much more agile Maltese Podarcis, I was surprised.

The lizards are also fearless and will venture very close to their human observers, especially if food is involved. They are endemic to Tenerife and belong to the species Gallotia galloti Oudart, 1839, which has differentiated into four subspecies around the same island and its neighbours. The ones in the following pictures are from the northern population of Gallotia galloti eisentrauti Bischoff, 1982 in Puerto de la Cruz, Tenerife.

It can be seen here that males are characterized by the larger size and a neon-blue throat, together with several other markings not found in females, which on the other hand are smaller and covered in brown patterns.

male specimen of Gallotia galloti eisentrauti Bischoff, 1982 basking in the sun

male Gallotia galloti eisentrauti Bischoff, 1982

female Gallotia galloti eisentrauti Bischoff, 1982 on the alert

The other subspecies are Gallotia galloti galloti (Oudart, 1839) from southern Tenerife, Gallotia galloti insulanagae Martin, 1985, from the isolated and inaccessible island northeast of Tenerife (Roque de Fuera de Anaga), and Gallotia galloti palmae (Boettger & Müller, 1914) from the island of La Palma.

The lizards are also an icon of the Guanche (aboriginal/ pre-Hispanic) culture on Tenerife, with several depictions and rock carvings still existing and on show in museums. They also ensure a steady income from tourists, their (highly non-realistic) outlines being featured on everything from ashtrays to t-shirts (though I must admit I had to buy one of the latter).

Los Gigantes cliffs in Tenerife

The highest cliffs in the volcanic island of Tenerife, in the Atlantic Ocean, are found on its western side. These majestic geological features are known as 'Los Gigantes' (the Giants), a term which perfectly befits their massive presence.

Acantilados de Los Gigantes, Tenerife

The cliffs are (like much of the island) composed of 'alkali' basalt, a volcanic rock which contains high proportions minerals like feldspar, olivine and iron oxides. These mineral accretions are sometimes large enough to be seen with the naked eye:

feldspar (white crystals) and iron oxides (brown aggregate) in basalt

feldspar (white crystals) and iron oxides (brown aggregate) in basalt

olivine (greenish crystals) in basalt

The basalt is found in layers which are texturally highly varied, each layer indicating a different episode or process in the island's violent volcanic history. For example, the breccia-like ignimbrite forms when a stream of lava partly melts the substrate upon which it is flowing and drags the pieces of hot rock along, subsequently welding the fragments together into a pudding-like composition, in this case containing fragments of widely disparate size:

ignimbrite

Another rock which stands out visually is red ochre, which forms when hot lava passes over well-developed soils. It can be seen as a thin reddish line in the following photograph:

red ochre stratum

Over millions of years, boulders of basalt tumble down the cliffs and are rounded by wave and wind action.

boulders on the shore

As a rough habitat largely characterized by strong currents and abrasive basalt gravel, the interface between the sea and land is largely devoid of macrofauna, though some usual suspects make an appearance. Most notable of these are two Macaronesian endemics - the limpet Patella piperata Gould, 1846 and the periwinkle Littorina striata King & Broderip, 1832. Closer to mean sea level, Patella tenuis crenata d'Orbigny, 1840 makes an appearance. The third species of limpet that may be encountered on Tenerife is Patella ulyssiponensis Gmelin, 1791, though none of these were seen during this trip. 

Littorina striata King & Broderip, 1832

Littorina striata King & Broderip, 1832

Patella piperata Gould, 1846

Patella piperata Gould, 1846

Specimens of Osilinus sauciatus (Koch, 1845) were found in small clusters, mostly using deep cracks as shelter.

Osilinus sauciatus (Koch, 1845)

Waiter, there's a snail in my paella

While spending a few days in València, Spain, I was surprised at the general lack of snails and slugs even in the grassiest of places along the riverbanks. A cursory search in the huge public park resulted in the finding of just three Cochlicella barbara (L., 1758) specimens on a nightly 'romp', but then, the well-maintained and intensely cultivated area was perhaps not the optimum environment for worthwhile molluscan discoveries.

Part of Valencia from above

The Valencians have many exquisite traditional dishes, frequently making ample use of seafood and landsnails. In a particular market, I was surprised to see that three species of the latter are farmed and packaged separately for consumption. These are Theba pisana (Müller, 1774), Otala punctata (Müller, 1774) and Cantareus aspersus (Müller, 1774) (pictured beneath in respective order). All three species are also present in Malta, yet here only the latter is consumed.

I later found a sub-adult Otala punctata in my Valencian paella take-away.