Nomenclature

Species name:

Triglochin bulbosa subsp. laxiflora   Gussone

Author(s):

Giovanni Gussone;
   Italy, 1787-1866

Georges C.Chr. Rouy;
   France, 1851-1924

Common names:

Lesser Arrow-grass, Lax-flowered Bulbous Arrow-grass

Maltese name:

ħaxixa tal-Baħar tal-ħarifa

Plant Family:

Juncaginaceae   (Arrow-grass Family)

Name Derivation:

Triglochin = From the Greek treis (three) and glochis (pointed), alluding to the projections on the carpel (Greek)
bulbosa subsp. laxiflora = bulbous, having an underground bulb (Latin)
laxiflora refers to the well-spaced, lax flowers of the inflorescence; not in a dense cluster. (Latin)

Synonyms:

Triglochin laxiflorum

Remarks:

In Malta there is another subspecies, that is Triglochin bulbosa subsp. barrelieri which has larger inflorescences and rarer. -

Morphology

Specifications & Description

Life Cycle:

Perennial.

Growth Form:

GEOPHYTE (Bulbous/Rhizomous plants)

Habitat:

Rock water pools on garigues and valley sides. Also reported in damp sites in cultivated sites.

Frequency:

Frequent Although frequent in certain locations, it can be totally absent or very rare in others.

Localities in Malta:

Uncommon, but locally frequent in certain sites in Malta and Gozo, for example Mosta (Wied il-Ghasel), Melliha, Birzebbugia and Xlendi (Gozo).

Plant Height:

5-25cm.

Flowering Period:

Oct - Nov

Protection in Malta:

Not Protected by Law (LN200/2011 or LN311/2006)

Red List 1989:

This species has a threatened status and is listed in the Flora section of the National Red Data Book (Lanfranco, 1989)

Poison:

Data not available

A perennial, herbaceous delicate plant which grows from small beige bulbs, about 1-2cm long, and often some 3-5cm above soil level. It forms long, fibrous roots a small tuft of leaves, and later an erect scape (flowering stem) that grows about 12cm in length, but some describe it to reach even 25-30cm.

The leaves are formed after the first rains in Autumn. These are flexible with a narrow linear shape ranging from few centimetres to 20cm long, and not more than 3mm wide. Young leaves are found ascending from a common point in the soil, but then they curve down and lie on the ground when they grow longer. They have a shallow longitudinal furrow on both surfaces. Leaves are glabrous, shiny, and with a smooth margin.

In October, the plant forms an erect scape giving rise to 3-15 flowers, markedly spaced from each other, and held by a short pedicel. Each flower is made up of 2 whorls of 3 tepals each, one situated over the other by 1mm apart. The lower 3 tepals are found spreading out into 3 distinct structures, in contrast to the upper whorl where its 3 tepals are found erect, and overlapping each other forming a closed cup shaped structure. The lower tepals are pale green, often but not always with an apex flushed in maroon while the upper ones are green.

At the base of the lower tepals there are the 6 stamens, a pair at each tepal. They have a very short or no filament. The anthers produce large amounts of pale yellow pollen which can be clearly seen escaping away as 'sulphur dust' if the flower is gently flicked.

The upper tepals are found surrounding and partially enclosing the superior ovary which is longer from them. At the top of the ovary there are 3 stigmas which when mature and dry, they are visibly seen as triangular feathery white structures. After fertilisation, the tepals fall down and the ovary lengthens to a 3-carpel fruit.

The green, glabrous fruit are held by a shorter pedicel in an erect position, not appressed to the stem. It measures between 5-10mm long and is very slender, less than 2mm across. It consists of 3 carpels joined longitudinally to a common central axis. The apex is not joined, resulting in 3 tiny pointed projections. The seeds (3 per fruit) are liberated when the fruit splits open along the carpel length. They are very thin structures, linear and slightly curvet at the ends.

Information and Details

Nativity and distribution

According to  [383] , the countries of origin are Europe, South Africa and Asia Minor but  [332] only mentions that the plant is found in Italy and Algerie. The list of European sites that the plant is found by Flora Europaea is: Albania, Balareas Islands, Corsica, Crete, France, Greece, Spain, Italy, ex-Jugoslavia, Portugal, Sardegna and Sicily.  [WWW-158] . T. bulbosa (s.l) is found in the nature reserve of Fernkloof (Cape Town) [ref] and Perth, Australia as an alien [ref]

Toxic effects

According to  [399] , the related species - Marsh arrow-grass (Triglochin palustre) a native plant that is found sporadically across Canada in damp brackish or calcareous places contain a cyanogenic glycoside - triglochinin. This chemical becomes more abundant during times of moisture depletion within the plants. Occasional poisoning occurs with cattle and sheep in the lower Cariboo district of British Columbia. Similarly, Triglochin maritima is poisonous due to the same glycosid  [WWW-24] Hence it is possible that the toxin Triglochinin is also found in T. bulbosa s.l.  [SM]

Notes on the Nomenclature of Triglochin

When publishing the name Triglochin Linnaeus (1753) treated it as of neuter gender (T. palustre, T. maritimum). Bentham (1878) treated it as feminine, presumably on the basis that glochin is feminine, and he was followed by most subsequent Australian authors. Since the 1990s, however, there has been a general consensus to accept Linnaeus' original choice of neuter. However, the ICBN (Art. 62.2 (d.) Ex. 5 mandates a feminine gender for Triglochin, which is adopted in recent flora.

Personal Observations

Triglochin species on the Maltese islands
There are only 2 species from the Juncaginaceae family in Malta, and both are subspecies of the Triglochin bulbosa. Apart from T. bulbosa subsp. laxiflora, there is also present T. bulbosa subsp. barrelieri, which can be distinguished from the former by having more dense racemes, fruiting pedicels as long or longer than the fruit (never shorter) and flowers in Spring. This species is less common, and is locally frequent in few sites.  [SM]

Photo Gallery   (37 Images)

IMAGE: TGCLX-01
Photo of the small and rather inconspicuous flowers, which are about 4mm across.

IMAGE: TGCLX-02
Photo of flowers which have a 3-parted symmetry. It consists of 2 whorls of 3 tepals each, one over and apart the other. The tepals can be green, or flushed in purple-maroon.

IMAGE: TGCLX-03
Photo of flowers, which is often seen to have this white feather-like structure at the top. This is the stigma. The tepals of this specimen are more maroon than green.

IMAGE: TGCLX-04
Close up photo of 3 young flowers showing in detail the feathery stigma. There are three stigmas (one per carpel) and the feather-like structure makes it more efficient to capture pollen grains. This photo also demonstrates that when the stigma are mature, the anthers are still unripe (seen as closed pockets under the lower tepals.

IMAGE: TGCLX-05
Close up photo of adult (old) flowers where the pistil is already enlarged and the upper set of tepals fell off.

IMAGE: TGCLX-06
Photo of more mature flowers. They are held to the flowering stem by a short pedicel (seen in the lower flower) and hence the inflorescence is described as a lax (not dense) raceme.

IMAGE: TGCLX-07
Close up photo of a typical flower. One can observe that the lower tepals are spread out, and separate, while the upper ones are erect and overlap to form a cup-shaped structure around the ovary. The stamens are found in pairs just above each of the lower tepal.

IMAGE: TGCLX-08
Close up photo of flower (lateral view) showing the feathery stigma at the apex of the ovary. The style is not present in this species.

IMAGE: TGCLX-09
Photo of lateral view of two mature flowers with ovary developing into the fruit pod.

IMAGE: TGCLX-10
Close up photo showing the plumose white stigma - the female part of the flower to which pollen attaches itself for fertilisation.

IMAGE: TGCLX-11
Photo of flowering stalk bearing 4 flowers that are well spaced from each other, hence the epithet 'laxiflora'.

IMAGE: TGCLX-12
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IMAGE: TGCLX-13
Close up photo of a mature flower. Note the stamens placed at the base and above the lower tepals. As seen, the stamens do not have a filament. A pair of stamens is found at each tepal, hence making 6 stamens per flower.

IMAGE: TGCLX-14
Another close up image of one flower. The 3-merous symmetry is well shown in this photo.

IMAGE: TGCLX-15
Scanned image of the inflorescence. Flowers are arranged as a lax raceme.

IMAGE: TGCLX-16
Scanned image of the flowering scape.

IMAGE: TGCLX-17
Scanned image of 3 flowers.

IMAGE: TGCLX-18
Magnified scanned image of the flower to show in detail their morphology.

IMAGE: TGCLX-19
Scanned image of the inflorescence showing the 2 whorls of 3 tepals each, and the 3-parted pistil.

IMAGE: TGCLX-20
Magnified scanned imaged of lateral view of flower. The upper tepals have a terminal bristle like projection. They are almost always green, while the colour of the lower tepals vary from pale green, cream or mauve-maroon.

IMAGE: TGCLX-21
Photo of young plants showing the linear slender leaves.

IMAGE: TGCLX-22
Photo of leaves of a young plant. When small they are ascending to erect, but when they get taller (up to 20cm) the curve down and becomes prostrate to the ground. They are glabrous, bright green, and with an entire margin.

IMAGE: TGCLX-23
Leaves are very narrow (2mm c.) and long. The lamina is flat and is slightly furrowed at both upper and lower surfaces.

IMAGE: TGCLX-24
Scanned image of the plant showing the leaves and the inflorescence.

IMAGE: TGCLX-25
Photo of the preferred habitat of the plant - a shallow rockpool with moist soil. It can also be found in muddy soil in cultivated areas and in damp sand by the coast.

IMAGE: TGCLX-26
Photo of few plants in a rockpool.

IMAGE: TGCLX-27
Photo of plants with flowers. and fruit.

IMAGE: TGCLX-28
Photo of a flowering plant from Xlendi, Gozo.

IMAGE: TGCLX-29
Photo of a fruiting plant.

IMAGE: TGCLX-30
Scanned image of plant. A tuft of leaves and a single scape grows from underground bulb of the plant.

IMAGE: TGCLX-31
Scanned image of a small plant with few leaves and a few-flowered scape.

IMAGE: TGCLX-32
Scanned image of bulb which forms long fibrous roots.

IMAGE: TGCLX-33
Scanned image of a bulb, beige in colour and in this case, about 1cm long.

IMAGE: TGCLX-34
Photos of fruit in situ. They are slender structures between 5-8mm long, and around 1mm wide.

IMAGE: TGCLX-35
The fruit of this species consists of 3 carpels joined together longitudinally. The apex is not joined to a common point but instead it has a a 3-pointed apex.

IMAGE: TGCLX-36
Scanned image of the fruit. The pedicels are shorter than the fruit and keeps it erect but not appressed to the stem.

IMAGE: TGCLX-37
Magnified scanned imaged of the 3-carpel fruit. The fruit breaks open along the length of the carpel, each holding 1 long and slender seed.

IMAGE: TGCLX-38
Photo of the inflorescence and fruit capsules in situ.

IMAGE: TGCLX-39

IMAGE: TGCLX-40

Links & Further info