Systematics of the Octopleura Clade of Miconia (Melastomataceae: Miconieae) in Tropical America
Gamba, Diana
Almeda, Frank
Phytotaxa
2014
2014-09-24
179
1
1
174
42P99
Gamba & Almeda
Gamba & Almeda
2014
[196,698,943,968]
Magnoliopsida
Melastomataceae
Miconia
Plantae
Myrtales
107
108
Tracheophyta
species
quadridomius
nom. nov.
Openly branched shrub or small tree (1.5–) 2–6 mtall. Upper internodesrounded-quadrate, (2.1–) 3.2–4.9 cmlong, cauline nodes terete, nodal line absent. Indumentumon branchlets, petioles, surface of young leaves, primary and secondary veins adaxially, primary and secondary leaf veins abaxially, bracts apically, pedicels, hypanthia, calyx lobes abaxially, and exterior calyx teeth densely to copiously composed of ferruginous elongate slightly or moderately roughened trichomes 2–3 mmlong, each trichome deflexed and somewhat flattened, densely intermixed with an understory of clavate dendritic trichomes 0.1–0.3 mmlong with short to moderately long thinwalled (flattened) arms. Leavesof each pair slightly to commonly anisophyllous in size; the semiterete short petioles 0.8–1.5 mmlong, superficially canaliculate adaxially; larger blades 18–27 × 6.7–10.2 cm, smaller blades 7–16 × 2.5–6.5 cm, elliptic to elliptic-obovate, the base typically rounded, frequently becoming attenuate but ending in a rounded-cordate base, the margin serrulate to crenulate, the apex acuminate to caudate-acuminate, chartaceous; mature leaves adaxially with both the dendritic and elongate trichomes on the surface, primary and secondary veins becoming sparse to caducous with age, the tertiary and higher order veins glabrescent; abaxial surface glabrous, the tertiary and higher order veins sparsely and caducously covered with the general dendritic trichomes; 5-(7-)plinerved, including the tenuous marginals, innermost pair of secondary veins diverging from the primary vein 0.3–2 cmabove the base, forming a deeply tufted cavity beset with the general indumentum (acarodomatia?), areolae 0.3–0.4 mm, reticulation visible on both surfaces, adaxially the primary and secondary veins slightly impressed, the tertiary and higher order veins flat, abaxially the primary and secondary veins elevated and terete, the tertiary and higher order veins slightly elevated. Inflorescencesa congested axillary fasciculate glomerule 1–1.5 cmlong, sessile, unbranched, typically paired and seemingly cauliflorous on defoliated nodes; bracts 1.5–7 × 0.4–0.6 mm, subulate, thin, erect, with inconspicuous parallel venation, glabrous on the main surfaces but the general elongate roughened indumentum present at the apex, each bract seemingly branched, persistent to tardily deciduous in fruit. Flowers4-merous on thick pedicels 0.4–1 mmlong. Hypanthiaat anthesis 2.7–3 × 0.9–1 mm, free portion of hypanthium 1.3–1.7 mmlong, tubular to suburceolate, bluntly 8-ribbed, ridged on the inner surface, moderately scaly, the torus adaxially copiously beset with short-stalked glands with thinwalled short heads. Calyxopen in bud and persistent in fruit; tube 0.1–0.3 mmlong, adaxially with the same typeof glands as the torus, abaxially with the same vestiture as the hypanthium; lobes 1.5–2 × 0.8–1.1 mm, ovate-oblong, 108 Phytotaxa179 (1) © 2014 Magnolia Press GAMBA & ALMEDA the margin entire, the apex retuse to obtuse, the adaxial surface glabrous or minutely resinous-puberulent, reflexed at anthesis; exterior calyx teeth 1–1.5 mmlong, subulate, inserted at the base of the calyx lobes and barely spreading beyond them. Petals1.5–3.5 × 0.6–1 mm, oblong to linear-oblong, the margin entire, the apex roundedobtuse, white, glabrous on both surfaces, reflexed at anthesis. Stamens8; filaments 1.4–1.5 × ca. 0.2 mm, white, glabrous; anther thecae 1.3–1.5 × 0.23–0.36 mm, linear-oblong and slightly clavate, somewhat emarginate at the apex, opening by one dorsally inclined pore 0.1 mm; connective darker than the thecae, its prolongation and appendage 0.2–0.3(–0.5) mm long, the appendage lanceolate, bluntly acute at the apex, copiously gland-edged, the glands rounded and conspicuously stalked to 0.2 mmlong. Ovary4-locular, 3/4 to completely inferior, 1.3–1.45 mmlong at anthesis, the apical collar 0.3–0.4 × 0.55–0.65 mm, conic, copiously glandular-ciliate; style 5–7 mmlong, parallel-sided (i.e. terete), white, glabrous; stigma truncate to capitellate when dry. Berries2–2.5 × 2 mmwhen dry, globose and slightly oblate, bright orange when ripe, the hypanthium indumentum persistent in fruit. Seeds0.68–0.79 × 0.5–0.65 mm, pyramidal, brown; lateral symmetrical plane triangular, the highest point near the central part of the seed; antiraphal symmetrical plane suboblong; raphal zone circular to suboblong, ca. 40% the length of the seed; multicellular sculpture rugose throughout the seed; individual cells elongate, anticlinal boundaries channeled, irregularly curved; periclinal walls convex, low-domed to nearly flat, microrelief striate.
Additional specimens studied:— COLOMBIA. Chocó: Vía de Morro de Micoal “Mirador” por el camino hacia “Jurubidá” en dirección Sy posteriormente hacia “Copete de Pava” en dirección N, 6°5’N, 77°10’W, 0–100 m, 15 May 1990, Barbosa6598( MO, US); P.N. de Utría, Serraníaubicada al NE de la Ensenada de Utríapor la trocha llamada del M-19, 6°20’N, 77°20’W, 0–100 m, 12 June 1990, García-Cossio& Agualimpia500( CHOCO, MO); Hoya del Río San Juan, Quebrada Taparal, afluente del Río San Juan, 4°12’N, 77°8’W, 5–10 m, 28 March 1979, Foreroet al. 4247( COL, MO). Valle:( Buenaventura), Alongroad between Buenaventura and Málagavicinity of Bajo Calima, km 3.5.2 from main Cali-Buenaventura Hwy, at Gallinero, 4°0’N, 77°3’W, 100 m, 15 July 1993, Croat& Bay75749( MO); ( Buenaventura), Bajo Calima, Ca, 15 kmNof Buenaventura, Cartón de Colombiaconcession, Dindo area, 3°59’N, 77°2’W, 50 m, 26 March 1986, Gentryet al. 53646( MO, US); ( Buenaventura), Bajo Calima, ca. 10 kmdue Nof Buenaventura, Cartón de Colombiaconcession, 3°56’N, 77°8’W, ca. 50 m, 5 December 1981, Gentry35354( CAS, MO); ( Buenaventura), Bajo Calima, ca. 15 kmNof Buenventura, Cartón de Colombiaconcession, 3°56’N, 77°8’W, ca. 50 m, 18 February 1983, Gentry& Juncosa40492( MO); ( Buenaventura), Bajo Calima, Granja Agroforestal, 40 m, 29 March 1984, Devia491( MO, TULV); ( Buenaventura), Bajo Calima, Estación Agroforestal, Secretaría de Agriculturay fomento, Parte NEdel campamento, 40–60 m, 5 August 1979, Cabrera5181( CUVC, MO); ( Buenaventura), San Isidro, BosqueINDERENA-CONIF, 40 m, 5 March 1989, Devia& Prado2641( CAS, TULV); ( Cordoba), Dagua Valley, 80–100 m, 6 May 1922, Killip5119( US); La Trojita, Río Calima(región del Chocó), 5–50 m, 19 February 1944, Cuatrecasas16623( US). ECUADOR. Esmeraldas: Road Lita-Alto Tambo-San Lorenzo, km 6.9 from Lita, 0°52’24.6"N, 78°29’33.2"W, 720 m, 30 September 2001, Cottonet al. 1794( CAS, QCA). PANAMA. Comarca de San Blás: Headwaters of Río Nergalaalong continental divide, 350 m, 11 January 1985, de Nevers& Herrera4515( CAS, MO); Llano-Cartí Road, km 16, trail to creek on Atlanticdrainage, 250–350 m, 2 February 1989, Almedaet al. 6522( CAS, MO, NY, PMA); Nusagandi, Alongcontinental divide on El Llano-Cartiroad, Headwaters of Atlanticdraining creeks, 9°19’N, 78°15’W, 320 m, 12 August 1984, de Nevers& Pérez3694( CAS). Panamá: Along El Llano Carti-Tupileroad, 12 miabove Pan-Am Hwy, 200–500 m, 26 March 1973, Liesner1135( CAS, NY). Illustration:—None found.
Common names and documented uses:—None recorded. Habitat, distribution and ecology:— Local and uncommon in understories of rain forests, typically in deep shade and/or along streams in Panama, Colombiaand Ecuador( Fig. 16), at 0–720 m. Itis most common in the Bajo Calima region(part of the Chocó) in the department of Vallein Colombia. Itwas recently reported from Panama( Almeda 2009). Specimensfrom Ecuadorthat were previously attributed to this species are M. chocoensis. Phenology:—Collected in flower from January through March and from May through August; in fruit from February through March, June through September, and in December.
Etymology:—The specific epithet honors José Cuatrecasas (1903–1996), Spanish botanist and prolific collector of Colombian plants.
Discussion:—This distinctive species has an indumentum of elongate-roughened trichomes on vegetative and hypanthial parts, conspicuous 5-plinerved leaves and a poorly developed-sessile inflorescence. Almeda (2009) SYSTEMATICS OF THE OCTOPLEURACLADE OF MICONIA Phytotaxa179 (1) © 2014 Magnolia Press 109noted that the Panamanian populations differ from those in Colombiaby the presence of shorter bracts to 2 mmlong (vs. 6–7 mmlong) calyx lobes adaxially glabrous (vs. resinous-puberulent); we agree with these observations. In all other characters, the material from both countries is similar in foliar shape, indumentum details, and staminal and seed morphology. In M. quadridomiusthe leaves are plinerved, but there is a space formed in between the innermost pair of secondary veins and the primary vein before the point of divergence. This space may serve to house insects. Althought some ants were found in this leaf area among different specimens from the Bajo Calima region ( Colombia), the morphology of this structure is not a usual ant-domatium. It is more similar to an acarodomatium; further natural history studies are required in order to elucidate the function of this structure. This species is similar to M. chocoensis, but differs in the foliar plinervation and in lacking white furrowed glands on the leaves abaxially. In M. quadridomiusthe vegetative and hypanthial indumentum is ferrugineous (vs. white), and consists of prominently roughened flattened-deflexed trichomes (vs. slightly roughened). Miconia quadridomiusis also similar to M. approximata, which has vegetative pubescence that is shorter ( 0.3–0.7 mmlong vs. 2–3 mmlong), and the abaxial tertiary and higher order foliar veins densely resinous-glandular (vs. furfuraceous). In the protologue, Wurdack (1981)provides a detailed enumeration of the differences between these species. Conservation status:—Endangered EN B2ab(iii). Protected only in Colombiain the Ensenada de Utría National Park (Chocó); the threats include destruction of its natural habitat and the fact that it is not protected in other parts of its range.
1990-05-15
MO, US
Colombia
50
6.0833335
Via de Morro de Mico
1305
-77.166664
Choco
108
109
1
1990-06-12
CHOCO, MO
NE de la Ensenada de Utria & Garcia-Cossio & Agualimpia
Colombia
50
6.3333335
Serrania
1304
-77.333336
Utria
108
109
1
1979-03-28
COL, MO
Forero
Colombia
Hoya del Rio San Juan
8
4.2
Rio San Juan
1307
-77.13333
Quebrada Taparal
108
109
1
1993-07-15
MO
Croat & Bay
Colombia
Valle
100
4.0
Along
1307
-77.05
Buenaventura
108
109
1
1986-03-26
MO, US
Gentry
Colombia
Bajo Calima
50
3.9833333
Dindo area
1307
-77.03333
Ca
108
109
1
1981-12-05
CAS, MO
Gentry
Colombia
50
3.9333334
Buenaventura
1307
-77.13333
Bajo Calima
108
109
1
1983-02-18
MO
Gentry & Juncosa
Colombia
50
3.9333334
Buenaventura
1307
-77.13333
Bajo Calima
108
109
1
1984-03-29
MO, TULV
Bajo Calima & Granja Agroforestal
Colombia
40
Buenaventura
108
109
1
1979-08-05
CUVC, MO
Bajo Calima & Estacion Agroforestal & de Agricultura & Parte NE
Colombia
50
Buenaventura
108
109
1
1989-03-05
CAS, TULV
San Isidro & Prado
Colombia
40
Bosque
108
109
1
Cordoba
1922-05-06
US
Killip
Colombia
90
Dagua Valley
108
109
1
1944-02-19
US
La Trojita & Cuatrecasas
Colombia
28
Choco
Rio Calima
108
109
1
2001-09-30
CAS, QCA
Cotton
Ecuador
720
0.8735
Lita
1
-78.49255
Road Lita-Alto Tambo-San Lorenzo
108
109
1
Esmeraldas
1985-01-11
CAS, MO
de Nevers
Panama
350
Headwaters of Rio Nergala
Comarca de San Blas
108
109
1
Herrera
1989-02-02
CAS, MO, NY, PMA
Llano-Carti Road & Atlantic & Almeda
Panama
300
108
109
1
1984-08-12
CAS
de Nevers & Perez
Panama
Nusagandi
320
9.316667
El Llano-Carti
1300
-78.25
Along
108
109
1
1973-03-26
CAS, NY
Along El Llano Carti-Tupile & Liesner
Panama
350
Hwy
108
109
1
Panama
Panama, Colombia
Specimens
360
It
It
108
109
1