Myrcia gonini McVaugh
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Authority
Maguire, Bassett. 1969. The botany of the Guayana Highland-part VIII. Mem. New York Bot. Gard. 18: 1-290.
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Family
Myrtaceae
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Scientific Name
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Description
Species Description - Arbor fulvo-velutinus, foliis supra ab initio fere glabris, subtus strigosis; folia late ovata, 6-10 cm longa, 3.5-6.5 cm lata, 1.25-1.6-plo longiora quam latiora, apice rotundata vel obtusa, basi late rotundata vel subcordata; petioli crassi, 5-8 mm longi; nervus medius supra impressus; venae laterales utrinque 10-15, supra paullo impressae, subtus prominentes, elevatae, venulis supra valde reticulatis, subtus nullis; nervus marginalis tenuis, a margine 1-1.5 mm remotus; inflorescentiae 6-9 cm longae, 15-25-florae, floribus magnis, pedicellatis vel terminalibus sessilibus; pedunculus 2-3 cm longus compressus; bracteae mox deciduae; alabastra 6-7 mm longa pyriformia, basi campanulata vel turbinata, hypanthio 3 mm longo, intus hirsuto, in siccitate supra germen 1.5 mm producto; discus 6 mm latus, hirsutus, annulo staminali 1.5 mm lato; stylus 7 mm longus; calycis lobi rotundati, inaequales, maiores 3.5 mm longi, 5-8 mm lati, utrinque minute tomentosi, omnes e margine hypanthii partim secedentes; petala 5-6 mm longa; ovarium biloculare, loculis biovulatis. A small tree (according to Amshoff), velutinous with yellowish-brown hairs, the leaves glabrous above almost from the first, persistently but thinly strigose beneath, especially on the veins; leaves broadly ovate, 6-10 cm long, 3.5-6.5 cm wide, 1.25-1.6 times as long as wide, rounded or obtusely pointed at apex, broadly rounded to subcordate at base, the margins abruptly decurrent on the inner angles of the deeply channeled stout petiole 5-8 mm long; midvein impressed above; lateral veins 10-15 on each side, mostly slightly impressed above, prominent and elevated beneath, the intermediate ones hardly any; veinlets strongly reticulate above, not or scarcely visible beneath; marginal vein weaker than the lateral ones, 1-1.5 mm from the margin; leaves lustrous above, paler beneath; inflorescence 6-9 cm long, 2-3-times compound, with relatively few (15-25) large flowers, these often solitary and pedicellate along the branchlets, or the terminal ones sessile; peduncles 2-3 cm long, compressed; buds 6-7 mm long, pyriform, campanulate or turbinate at base; hypanthium 3 mm long, hirsute within; disk 6 mm wide, hirsute, the staminal ring 1.5 mm wide, the whole nearly flat and the center merely concave in soaked (and fresh?) flowers, but the ring in dried flowers elevated 1.5 mm above the base of the style; style 7 mm long, glabrous or nearly so; calyx-lobes broadly rounded, unequal, finely tomentose on both sides, at anthesis separated by short fractures at the edges, and partly deciduous from the hypanthium; larger lobes 3.5 mm long, 5-8 mm wide, the smaller 2 mm long, 3 mm wide; petals 5-6 mm long; stamens 200 or more; fruit unknown; ovary bilocular, with two ascending ovules in each locule.
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Discussion
This, the only known specimen of this species, was referred by Amshoff to Aulomvrcia grandiflora Berg, and well described by her under that name (Fl. Suriname 3(2): 71. 1951). The true A. grandiflora, based on a collection by Sellow from Minas Gerais, is apparently quite a different thing. I have seen what I suppose to be isotypes at C G E and at U (the latter annotated by Berg). The species is definitely an Aulomvrcia in the sense of Berg; the hypanthium in a soaked flower forms a cuplike structure about the summit of the ovary, nearly glabrous within, more than 1 m m high; the calyx-lobes are very broad and low, much shorter than the globe of the petals in bud, the larger ones 1.5 m m long, 3.5 m m wide at base, the smaller ones1 mm long, 2.5 mm wide, all dark, only sparingly hairy without, pubescent within, neither very widely spreading nor deciduous at anthesis; the ovary (according to Berg and Amshoff) is trilocular.
Apparently Myrcia gonini, M . calycampa and M . tafelbergica form an alliance within sect Armeriela. They are essentially sympatric, all as far as known restricted to Suriname and British Guiana; they are alike in the uniformly distributed soft tawny pubescence of the entire inflorescence, in the broad soft calyx-lobes that separate easily from one another and from the hypanthium, and in the relatively flat disc with broad hirsute staminal ring.
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Distribution
SURINAME . "Fluv. Gonini," 20 Feb 1918 (fl), Gonggrijp 3787 (U, type).
Suriname South America|