Mortoniodendron uxpanapense Dorr & T. Wendt
Descripción
TREE to 10-12 m tall, spreading, low branched. TRUNK to 40-45 cm diam. near base (below branching); BARK ashy-brown to dull reddish-brown, general aspect :±: smooth, fine aspect irregularly finely undulate to asperous, with scattered to crowded lenticellar warts; SLASH of bark with no prominent odor, the very thin outer layer reddish-brown, the rest light yellowish-brown, the sapwood cream-colored to almost white. Ultimate BRANCHLETS 2-3 mm thick, completely covered by a dense layer of flat stellate trichomes mostly 0.07-0.15 mm in diam. (with or without quite scattered larger trichomes of similar form), this indumentum so fine, uniform, and appressed that branchlets may appear glabrous without sufficient magnification, each trichome with ca. 8-20 rays all spreading and :±: parallel to surface, the rays :±: fused irregularly near bases. LEAF BLADES thick but not coriaceous, elliptic to slightly obovate, mostly 15-24 cm long by 5.3-9.2 cm wide when mature, 2.4-3.4 times as long as wide, finely but distinctly pellucid-punctate due to mostly circular to oblong internal mucilage cells variable in size, the blade apex gradually to abruptly acuminate, the acumen ca. 1-2 cm long, the base broadly acute to rounded, very slightly oblique; VENATION actinodromous in lower portion, :±: brochidodromous distally, with 5-8 lateral veins per side, the lowest pair arising 1-3 mm above the blade base and most often at a narrower angle (25--40°) to the midrib than the distal ones ( 45-65° in distal half blade), this near-basal lateral pair giving a slightly triplinerved aspect to many leaves but these veins the same size as the other laterals and not obviously further spaced than the others, a smaller pair of thinner lateral veins (tertiary venation size) arising with or just below the near-basal pair and paralleling the basal portion of the blade margin, the tertiary venation strongly scalariform, the finer venation subscalariform to coarsely reticulate, the midvein slightly sunken to plane above, all other veins finely raised above, all veins raised beneath, the midvein and laterals prominently so; VESTITURE of blade adaxially lacking or essentially so, abaxially the midvein sparsely to moderately beset, especially toward the base, with minute stellate hairs like those of stem, such hairs otherwise very scattered on finer venation and leaf surface, the axils of the lateral veins each usually with an extremely inconspicuous concentration of minute appressed stellate hairs like those of rest of blade, the rays of these only occasionally elongated (to 0.5 mm) and erect to form a still rather inconspicuous axillary tuft. PETIOLES of mature leaves 11-22 mm long, slightly thickened-pulvinate distally, with dense stellate indumentum like stem. STIPULES linear, dark (at least when dry), ca. 4-8 mm long, fugaceous, with scattered stellate hairs. CYMES mostly 1--4 flowered, solitary in upper 1-3 leaf axils and/or terminal and. then sometimes paired, to 8 cm long, the branches and pedicels divergent, the axes and pedicels with indumentum like that of the branchlets but also with abundant larger (0.2-0.3 mm diam.), less appressed and more reddish stellate hairs mixed in; PEDUNCLE 2-20 mm long; BRACTS ca. 1-1.5 mm long, fugaceous; PEDICELS 19--40 mm long, distally thickened, not articulate. FLOWERS ± nutant; SEPALS 5 (or 6, fide A. Rodriguez), spreading, very thick, white, each one ovate, with sharply acute apex, 11-18 mm long, 4-6 mm wide, eventually caducous, abaxially densely stellate-tomentose like the pedicels, adaxially with much less dense covering of tiny unkempt weak-rayed stellate hairs, this very dense near tip; PETALS 5 (or 6, fide A. Rodriguez), spreading, thin, white (apparently becoming purplish after anthesis, dark brown when dry), each one ± narrowly rhombic or somewhat clawed with a trullate blade, 7-12 mm long, 2.5-3 mm wide, with a long narrowly acute apex, quickly caducous after anthesis, abaxially rather densely beset with minute stellate hairs in center, adaxially only distally and very lightly so; STAMENS ca. 72, some seemingly short-connate at filament bases but definitely not forming a set number of distinct fascicles of connate stamens, all lightly coherent and inflexed around style at anthesis, the outer stamens much longer than the inner ones due mostly to longer filaments, the filaments white, broad, those of the outer stamens to 6 mm long and 0.6-0.9 mm broad, those of the inner stamens as short as 2 mm, the anthers orange-brown, linear-lanceolate, the same width as the filaments, 4-6 mm long, narrowly acute, each with a terminal narrowly conical appendage 0.2- 0.5 mm long; OVARY ca. 5-6 mm long, ovoid, 4-5-angled, externally densely stellate-tomentulose, the locules 4-5, glabrous within, with ca. 10-12 ovules/locule, these biseriate, the style ca. 4 mm long, tomentulose in basal one-fifth to three-fourths, distally glabrous. FRUIT a loculicidally dehiscent woody capsule, subglobose with 3- 5 flattened sides in cross-section and slightly ribbed along sutures, ca. 25-30 mm long, ca. 25-35 mm wide (before dehiscence), externally very finely and densely stellate-tomentose, greenish brown, the outer walls thick, woody, ca. 5 mm thick at mid-fruit; FERTILE LOCULES 3-5, glabrous within, each with 1-3 seeds. SEEDS brown, subglobose to ellipsoid (often irregularly so by compression), ca. 8-10 mm long; TESTA smooth to minutely verruculate, the hilum conspicuous, 2.0-2.5 mm long; ARIL thin, orange, ± completely covering seed.A
Distribución
México (país) EndémicoA
Elevación
200 – 250 mA
Tipo de vegetación
Selva altaA
Categoría IUCN
En peligro crítico (CR)B
Categoría NOM-059-SEMARNAT-2010
No incluidaC