Neblinaria Maguire
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Authority
Maguire, Bassett. 1972. The botany of the Guayana Highland--part IX. Mem. New York Bot. Gard. 23: 1-832.
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Family
Theaceae
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Scientific Name
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Description
Latin Diagnosis - Flores solitarii, grandi, roseo-albi; bracteis subfoliaceis, pedicellis subtendentibus; pedunculis valde ancipitis; sepalis quincuncialibus; staminibus numerosis, liberis, antheris 4-thecatis; pollinibus tricolporatis, oblatis, crasso-exineis; ovario 3-loculari, placentatione axillari, gemina; capsula septicidali; seminibus glabris, oblongis. Arbor parva, pachyderma; foliis multi-parallelo-venatis.
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Discussion
Type. Neblinaria celiae Maguire. Unispecific.
Neblinaria is strongly marked, having strongly compressed, conspicuously whorled-bracted peduncles, and coriaceous sessile multi-parallel-veined naviculoid conferted leaves. In its bizarre candelabraform habit, Neblinaria forms a conspicuous element of open savanna habitats on the summit of Neblina.
Young Stems.
The nodal anatomy and that of the young shoot of Neblinaria would be very difficult to interpret because of the highly conferted, rosette leaf disposition at the short grossly thick ends of the pachydermic terminal shoots. This, coupled with the probability of a polylacunar node, as reflected by the entry of some seven vascular strands into the leaf base, would of necessity create an enormously complicated plexus of stelar branching at any given nodal level. Leaf scars show a crescent of 5-7 distinct vascular strands.
Leaves.
Sections of the broad sessile leaves reveal just above the point of juncture the large open nearly circular central trace and five or more lateral traces on either side, the small ones apparently not visible in leaf scars. At the first level that a complete section may be obtained, there are at least six pairs of lateral traces and evidence of considerable trace branching.
Soon the central trace opens into a broad V with the lateral recurved ventral portions becoming separated as distinct, ventrally placed strands. Still farther upwards, the central strand becomes diminished and finally loses identity. In this region the parallel venation of the leaf is established.
The blade presents an almost monocotyledonous aspect. Cuticle is more prominent on the dorsal side, with even rectangular epidermal cells 60-70 X 20 µ in section. A prominent 2-celled hypodermis consists of considerably larger cells. The lower epidermis consists of a thin cuticle, smaller epidermal cells, also with a 2-layered hypodermis of smaller cells. Hypoderm cells are without cloroplastids. Stomata are provided with two ledges, the guard cells dorsiventrally partially enclosed by the two nearly enveloping supporting cells.
The palisade mesophyll occupies the middle portion of the leaf, and is six or eight or more cells in depth. Spongy mesophyll is scanty.
The numerous discrete, dorsiventrally oblong (in section) veins are immersed in the palisade mesophyll. Each vein is provided with a single-celled layer dark-staining pericycle and an inner zone of mechanical cells.