Adelobotrys saxosa Wurdack

  • Authority

    Maguire, Bassett & Wurdack, John J. 1964. The botany of the Guayana Highland--Part V. Mem. New York Bot. Gard. 10: 1-278.

  • Family

    Melastomataceae

  • Scientific Name

    Adelobotrys saxosa Wurdack

  • Description

    Latin Diagnosis - A. fruticosae Wurdack affinis sed foliis subtus glabratis inflorescentia expansa hypanthio vix striguloso calycis lobis interioribus minoribus rotundatis. Arbor gracilis 2-8 m alta; rami robusti primum petiolis inflorescentiis hypanthiisque sparse strigosi (pilis debilibus gracillimis) mox glabrati. Petioli 1.5-3 cm; lamina (5-)7-15 X 3-7 cm elliptica apice obtusa et minute (ad 2 mm) mucronata basi obtusa coriacea, supra et subtus primum sparse strigulosa (pilis gracillimus) mox (nervis primariis subtus exceptis) glabrata 5- vel sub-7-nervata nervis secundariis parce distinctis tertiariis non evolutis, ad margines densissime ciliata pilis gracilibus primum ravis demum fuscis. Inflorescentia 10-20 cm longa racemiformis angusta verticillato-interrupta verticillorum singulorum floribus 4-8; pedicelli 2-5 mm longi; flores 5(-6)-meri. Hypanthium (ad torum) 8-9 mm longum; calycis tubus 2 mm longus, lobis interioribus ca. 1-1.5 X 3 mm obverse ellipticis, dentibus exterioribus anguste acutis ca. 1 mm eminentibus. Petala 22-25 X 11-15 mm asymmetrice obovata apice hebeti-obtusa. Stamina dimorphica. Stamina maiora: filamenta 10-11 mm longa; antherae 10 mm longae curvatae subulatae, connectivo basi dorsaliter dente acuto 0.7-1 mm alto et appendice adscendenti truncata 3.5-4 mm longa. Stamina minora: filamenta 11.5-12 mm longa; antherae 5.5-6.1 mm longae, connectivo basi dorsaliter dente acuto ca. 0.3 mm alto et appendice adscendenti 3-4 mm longa. Stylus 10.5-13 X 1.3-0.5 mm; stigma punctiforme; ovarium 3-loculare glabrum apice in collum 0.7 mm altum protractum.

  • Discussion

    Type. Petals pink, frequent on slopes of Piedra Arauicaua, Rio Yatua, Terr. Amazonas, Venezuela, alt. 150-500 m, 15 Jul 1959, J. J. Wurdack & L. S. Adderley 43451 (holotype U S 2342634). Paratypes. VENEZUELA, Terr. Amazonas. Rio Yatua: Piedra Arauicaua, Maguire, Wurdack dc Bunting 37473, Maguire, Wurdack & Meiguire 41610. Rio Siapa: crystalline dome on right bank of river just below Raudal Gallineta, alt. 300-700 m, Wurdack & Adderley 43543.

    A. fruticosa (now known at anthesis by the topotypical Maguire, Wurdack, & Keith 41798) has lower leaf surfaces and hypanthia densely and persistently fine-strigulose, sessile or scarcely (to 1 cm) pedunculate inflorescences, and ovate interior calyx lobes 2.5-3 mm long. A. barbata Triana, apart from the distinctive lower leaf surface malpighian hairs, has inflorescences usually trifurcate from at or near the base, as well as densely pubescent hypanthia. The Peruvian A. macrantha Gleason, described as arborescent, has thinner larger acute leaf blades with prominent secondary nerves, as well as flower verticels on lateral branchlets and non-emergent external calyx teeth. The holotype (K) oifA. rotundifolia Triana, from forests along the Rio Casiquiare, has been examined; that species apparently has a vining habit, branched inflorescences with less robust axes, finer marginal leaf hairs, and (judging from the fruit) much smaller flowers. A. saxosa is abundant on the piedra slopes at both known localities, but is definitely a rainy-season flowerer; the Arauicaua paratypes are in young (Sep 27) and old (Feb 3) fruit.