Desmazeria pignattii
| Desmazeria pignattii | ||||||||||||
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| Scientific name | ||||||||||||
| Desmazeria pignattii | ||||||||||||
| Brullo & Pavone |
Desmazeria pignattii is a species ofthe sweet grass family (Poaceae). It is considered endemic with an extremely limited habitat and is only found in Malta and southern Sicily.
description
Desmazeria pignattii is an annual, in clumps growing grass . The hairless stalks are 2 to 6 (rarely up to 10) centimeters long, creeping to seldom erect, completely to almost completely sheathed. The hairless leaf blade is linear-pointed, 15 to 50 millimeters long and 1 to 2 millimeters wide, rolled up and often rolled up. The ligule is split, 0.5 to 1 mm long and translucent.
The leaf blade is narrow, thick and has 9 to 11 ribs. The ribs are triangular in cross-section and carry scattered bristle hairs. The leaf surface facing away from the axis has an epidermis of large cells, has a thick cuticle and is sparsely covered with stomata . Only on the edge of the leaf are the epidermal cells smaller and the cuticle thin. The palisade parenchyma is a layer of cells thick and well developed, the remaining mesophyll is formed by a dense sponge parenchyma . The axially facing leaf surface is characterized by the ribs, the surface of which is formed by large, irregular cells between which numerous stomata stand. The vascular bundles have a small diameter and are located under the ribs. Sklerenchyma is located on the edges of the ribs and on the edges of the leaves.
The inflorescence is a two-line, firm spike , 1 to 3 centimeters long and consists of six to eight (rarely four to ten) spikelets , their stalks are 0.5 to 1 millimeter long. The seven- to ten-, rarely up to twelve-flowered spikelets are ovate, laterally compressed, 5 to 7 millimeters long and 2 to 3 millimeters wide. The glumes are homogeneous, ovate, acuminate, laterally keeled, about 3 millimeters long; the lower glume pointed, 1.5 millimeters wide and five-veined with a long and strongly protruding central rib and side ribs, the other veins are extremely short and inconspicuous. The upper glume is obtuse, 2 millimeters wide, seven-veined, the midrib is long and protruding, the rest of the veins are short and inconspicuous. The hairs are cylindrical to approximately club-shaped in the spikelet axes and on the lateral attachment of the lemma , unicellular and 0.15 millimeters long. The lemmas are ovate and rounded, tapering to a point and 3 to 3.5 millimeters long and 2.5 millimeters wide, seven-veined with a long and prominent central rib, the two outer side ribs are short, the two directly to the side of the central rib are inconspicuous, the surface is leathery and translucent along the wide edge. The palea is translucent, narrowly lanceolate, 3 millimeters long, laterally double keeled and closely ciliate on the nerve. The two lodiculae are egg-shaped, blunt at the extreme end and loosely ciliate towards the edge.
The flower has three stamens , the anthers are yellow, linear and 0.7 to 0.8 millimeters long. The ovary is hairless and 0.5 millimeters long. The two styles are hairy with short down and about 2 millimeters long. The yellowish-brown caryopsis is obovate, around 1.5 millimeters long and 1 millimeter wide. It is furrowed on the side of the umbilical spot.
distribution
Desmazeria pignattii is rare. The species is a so-called Maltese-Hyblean endemic , so it is only found in Malta and southern Sicily. There it colonizes dry, calcareous soils of the littoral in almost halophilic microassociations of annual plants amid the perennial plant communities of the Crithmo-Limonietea . The similar Desmazeria rigida can be found in the same habitats in Malta , but its leaves are larger and lanceolate.
Systematics and botanical history
Desmazeria pignattii was first described in 1985 by Salvatore Brullo and Pietro Pavone , the specific epithet honors the Italian botanist Sandro Pignatti . The species is closely related to Desmazeria sicula .
proof
- ↑ a b c d e f S. Brullo, P. Pavone: Taxonomic Considerations on the Genus Desmazeria (Gramineae) with Description of a New Species: Desmazeria pignattii In: Willdenowia, Vol. 15, H. 1, 1985, p. 99 -106
- ^ Hans Christian Weber, Bernd Kendzior: Flora of the Maltese Islands - A Field Guide , 2006, ISBN 3-8236-1478-9 , p. 74