Vellozia dasypus Seub.

Vellozia dasypus Seubert

Vellozia dasypus Seubert in Martius, Fl. Bras., 3(1):81, 1847.—L. B. Smith, Contr. U.S. Nat. Herb., 35:266, 1962.—Ayensu, Smithsonian Contr. Bot., 15:20, fig. 13c–e, pls. 16a, 33d–h, 34a, 1974.

TYPE.—Jacobina, Bahia, Brazil, Blanchet 3558 (G, holotype; F, photo 25077).

DISTRIBUTION.—Brazil: Sergipe: Serra de Itabaiana. Bahia: Maraú, Mucugê (Serra de Sincorá), São Salvador.

85. Vellozia scabrosa L. B. Smith & Ayensu, new species

A V. exilis Goethart & Henrard atque V. grisea Goethart & Henrard, quibus affinis, caudice robusto, scapis elongatis differt.

Caudex branched, 2 m high (!Hatschbach), 12 mm thick at apex (including leaf-sheaths), appearing much thicker because of the short erect branches. Leaves ca. 10-ranked, glabrous; sheaths densely imbricate with apex slightly exposed; blades of uncertain duration because old leaves badly burned, linear, attenuate to an oblique obtuse apex, to 14 cm long, 8 mm wide at base, flat, the thickened margin very finely serrulate toward base, elsewhere entire.

Scapes terminal, 2–4, erect, to 8 cm long (above the leaf-sheaths), densely scabrous. Ovary obovoid, 11 mm long, densely scabrous; epigynous tube short. Tepals elliptic, 3 cm long, violet (!Hatschbach). Stamens ca. 18; phalanges lacerate-appendaged.

LEAF ANATOMY (Hatschbach 29970).—Surface View: Hairs: none observed. Epidermis: cells on both surfaces square to rectangular; thin-walled. Stomata: tetracytic, 18 × 9 μm on abaxial, slightly shorter and wider on adaxial; stomata in rows on adaxial surface and in abaxial furrows.

Transverse Section of Lamina: Dorsiventral; widely V-shaped with small median adaxial groove. Adaxial surface slightly ridged; abaxial furrowed ⅓ to ½ thickness of blade. Epidermis: cells on both surfaces square to rectangular and crescent-shaped; thin-walled. Subjacent to adaxial epidermis in some places are 1–3 layers of sclerenchyma fiber bundles; there is a layer of small, thin-walled parenchyma

below epidermis; sclerenchyma fiber bundles occur below this layer followed by another parenchyma layer subjacent to the bundles. Similar distribution of sclerenchyma and parenchyma occur on abaxial side, except that sclerenchyma is one layer thick. Cuticle: thick and slightly ridged on adaxial surface; thick and very ridged with cone-like projections on abaxial surface. Stomata: present on adaxial surface and in abaxial furrows; stomata flush with epidermal surface; small substomatal chamber present. Mesophyll: 3 or 4 layers of palisade tissue followed by compactly arranged cells. Three or four layers of large translucent cells radially arranged above furrows and tangentially on vascular bundles; mesophyll above midvein almost entirely translucent. Vascular bundles: 33; few commissural bundles observed. One or two large vessels in each bundle, mostly one. Two phloem units lying laterally in flanges of fairly thick, Y-shaped to deeply U-shaped abaxial girder. Large adaxial cap present on each bundle. Bundle sheath completely surrounding each vascular bundle. Crystals: none observed. Tannins: present.

TYPE.—Jaboticatubas: Rocky campo, Serra do Cipó, Minas Gerais, Brazil, 6 August 1972, Hatschbach 29970 (US, holotype; MBM, isotype).

DISTRIBUTION.—Known only from the type-collection.

Vellozia dasypus Seubert

SPECIMENS EXAMINED.—Belém and Pinheiro 3179; R. de Lemos Fróes 20246; Rose and Russell 19697; Blanchet 3558.

SURFACE VIEW.—Hairs: absent. Epidermis: adaxial and abaxial cells mostly of square cells, occasionally rectangular cells are observed. Stomata: paracytic, 24 × 12 μm; occur on both surfaces especially in furrows of abaxial surface.

TRANSVERSE SECTION OF LAMINA.—Dorsiventral; V-shaped to nearly inversely W-shaped with median adaxial groove. Adaxial surface ridged; abaxial surface furrowed about one-fifth to one-seventh of blade thickness. Epidermis: cells more or less square; abaxial cells almost replaced by fibers except in furrows. Distinct cuboidal sclerenchyma strands, separated from each other by three to four radial rows of parenchyma, occur subjacent to adaxial epidermis. Cuticle: uniformly thickened. Stomata: present on both surfaces, particularly in abaxial furrows. Mesophyll: adaxial palisade two to three layered; palisade separated from adaxial sclerenchyma strands by one layer of distinct translucent parenchyma cells; two to five radially oriented large translucent cells arranged adaxially on vascular bundles. Palisade cells compactly arranged and filled with chloroplast; palisade occupying about one-third of mesophyll and abruptly changing into almost tiered spongy cells. Vascular bundles: 27–33; commissural bundles present. Large veins each with one to two large vessels, mostly one. Two phloem units lying laterally in flanges of abaxial Y-shaped girder. Each vascular bundle always accompanied by adaxial inverted V-shaped sclerenchyma cap; both in turn completely surrounded by a distinct bundle sheath. Crystals: not observed. Tannin: present but few in mesophyll.

NOTE: The four specimens under study share similar histological details except that the median abaxial surface in one (R. de Lemos Froes 20246) is much broader than the others, and the adaxial inverted V-shaped sclerenchyma in one of the four specimens (Russell 19697) is much more pronounced, especially at the middle of the intercostal region.

Vellozia dasypus là một loài thực vật có hoa trong họ Velloziaceae. Loài này được Seub. miêu tả khoa học đầu tiên năm 1847.