Five new South American species of Myrcia s. l. (Myrtaceae)
Author
Santos, Matheus F.
Universidade de São Paulo, Departamento de Botânica, Laboratório de Sistemática Vegetal, Rua do Matão 277, São Paulo, SP 05508 - 090, Brazil.
Author
Lucas, Eve
Herbarium, Royal Botanic Gardens, Kew, Richmond, Surrey TW 9 3 AB, United Kingdom.
Author
Sano, Paulo T.
Universidade de São Paulo, Departamento de Botânica, Laboratório de Sistemática Vegetal, Rua do Matão 277, São Paulo, SP 05508 - 090, Brazil.
text
Phytotaxa
2015
2015-11-13
234
2
159
171
http://dx.doi.org/10.11646/phytotaxa.234.2.6
journal article
10.11646/phytotaxa.234.2.6
1179-3163
13632903
5.
Myrcia subterminalis
M.F.Santos
,
sp. nov.
(
Figs. 2
,
4F–I
)
Myrcia subterminalis
is related to
Myrcia bicolor
Kiaersk.
, but differs in the predominantly monopodial vegetative branching (vs. sympodial), the terminal and subterminal inflorescences (vs. only terminal) and turbinate floral bud (vs. clavate).
Type
:—
BRAZIL
.
Espírito Santo
: Mun. Santa Teresa, Reserva Biológica Augusto Ruschi, Próximo ao marco 112, seguindo o córrego,
27 August 2003
(fl.),
J. Rossini 482
(
holotype
MBML!,
isotypes
SP!,
SPF
!).
Tree
3–
15 m
. Immature parts sometimes with epidermal peeling; trichome light brown (rarely ferruginous),
0.1– 0.2 mm
long, dibrachiate.
Twig
when immature reddish, flattened, sometimes with longitudinal grooves, not keeled, with scattered trichomes to glabrous; mature twig greyish, cylindrical, cortex slightly cracked, glabrous; branching monopodial (rarely sympodial), 2–3 branches per node (rarely more than three), epidermal protrusion absent at the internodes (present only in sympodial branching), internode
2.5–6.8 cm
long; cataphyll foliaceous, 7 ×
2 mm
, usually only at the basal internodes, early deciduous, adnate, lanceolate, externally puberulent; branch with 1–3 apical buds, pubescent or puberulent.
Leaf
discolorous, chartaceous, blade 5.0–14.5 ×
1.4–5.9 cm
, elliptic, widely elliptic, ovate or obovate, apex caudate, base atenuate, cuneate or obtuse, margin plane, secondary veins
3–6 mm
apart, held at an angle of 65–85
o
relative to the midvein, marginal vein 1.0–
1.5 mm
from the margin (rarely two), tertiary veins conspicuous (rarely inconspicuous); adaxial surface glabrous, midvein sulcate in the first half and flat in the second half, secondary veins flat (rarely prominent), pellucid dots inconspicuous, from 5 to 15 per mm
2
; immature abaxial surface with scattered trichomes to glabrous, glabrous at maturity, midvein and secondary veins prominent, pellucid dots slightly conspicuous to inconspicuous, from 5 to 15 per mm
2
; petiole 3–10 ×
1–2 mm
, canaliculate to semicylindrical, immature with scattered trichomes, mature glabrous.
Panicle
3.5–7.0 ×
2.5–3.5 cm
, pyramidal, terminal axillary or subterminal, 14–70 flowers, rachis puberulent or with scattered trichomes to glabrous, branching 1–5 times at the base, first internode of central rachis 1.0–
1.5 mm
wide, cylindrical to flattened, distal internodes flattened, opposite branching (rarely subopposite), 2–5 branches per node, epidermal protrusion present at the internodes, usually absent in apical branches.
Bract
0.8 ×
0.2 mm
, deciduous, lanceolate or ovate, concave, apex acuminate, base truncate, adaxial surface glabrous, abaxial surface puberulent.
Pedicel
0–2 mm
long, cylindrical, puberulent.
Bracteole
0.4–0.6 ×
0.2 mm
, deciduous, lanceolate or ovate, concave, apex acuminate, base truncate, adaxial surface glabrous, abaxial surface puberulent to glabrous.
Floral bud
2–3 ×
1–2 mm
, turbinate.
Hypanthium
extending 0.6–1.0 mm above the summit of the ovary, not tearing at the anthesis, externally with scattered trichomes to glabrous, pellucid dots slightly conspicuous, covering the whole surface, internally glabrous; calyx 4–5-merous, lobes 0.4–1.0 ×
0.6–1.8 mm
, distinct from the hypanthium, external lobes smaller than the internal lobes, deciduous, depressed ovate, widely depressed ovate or ovate, concave, apex rounded, base truncate, externally with scattered trichomes to glabrous, internally puberulent to glabrous; corolla 4–7-merous, petal white, 0.8–2.0 × 1.0–
1.8 mm
, depressed ovate, widely depressed ovate, widely ovate or very widely ovate, concave, apex rounded, base truncate, externally puberulent or with scattered trichomes to glabrous, internally glabrous; staminal ring
0.2–0.4 mm
wide, glabrous, stamens 38–60, filament 1.6–5.0 mm long, glabrous, anther 0.24– 0.40 ×
0.24–0.48 mm
, square, oblong or transversely oblong; ovary 0.6–1.0 ×
0.8 mm
, 2-locular, each locule with two ovules, style
3.6–5.2 mm
long, glabrous, stigma punctiform, papillose.
Fruit
green when immature, reddish at maturity, 7 ×
6 mm
, depressed globose or globose, glabrous, pellucid dots covering the whole surface, remnants of calyx lobes present or not; seeds 1–2.
Distribution and Habitat
:—
Myrcia subterminalis
occurs in the Atlantic Forest domain, in submontane to montane rainforest (
Alagoas
,
Bahia
and
Espírito Santo
states) and in semideciduous forest (municipality of Bandeiras—
Minas Gerais state
).
Phenology
:—
Myrcia subterminalis
flowers from July to September and in November. Fruits were found from September to January.
Etymology
:—The specific epithet refers to the presence of subterminal inflorescences in this species.
Conservation status
:—The species presents an Area of Occupancy smaller than
2,000 km
2
and is only recorded from few (six) localities. Moreover, it is endemic to the Atlantic Forest, a phytogeographic domain reduced to only 7.5% of its original extent (
Myers
et al.
2000
).
Myrcia subterminalis
is here considered as Vulnerable (VU, criteria B2a, biii;
IUCN 2001
).
Discussion
:—
Myrcia subterminalis
resembles
Myrcia bicolor
but differs in its predominantly monopodial vegetative branching, terminal and subterminal inflorescences and turbinate floral buds.
Myrcia subterminalis
is also characterized by a strongly canaliculate petiole, leaf blades with decurrent bases and the lightly reticulate venation. Sympodial (dichotomic) branching is rarely present, but in this case one of the branches develops faster than the other and the branching becomes monopodial.
Paratypes
:—
BRAZIL
.
Alagoas
:
Mun. União dos Palmares
,
Serra das Bananeiras
,
500–560 m
,
9
o
12’7.75’’S
,
35
o
52’4.8’’W
,
3 November 2002
(fr.),
W.W. Thomas
13253
(
CEPEC
!).
Bahia
:
Mun.Almadina
,
Serra do Corcovado
,
831 m
,
14
o
42’21’’S
,
39
o
36’14’’W
,
3 September 2011
(fl.),
M.M. Coelho
360
(
CEPEC
!).
Mun.Arataca
,
1000 m
,
15
o
10’2.5’’S
,
39
o
20’3’’W
,
12 October 2005
(fr.),
A.M.A. Amorim
5313
(
CEPEC
!)
;
Parque Nacional da Serra
das
Lontras
,
26 November 2011
(fl.),
M.F. Santos
757
(
SPF
!)
;
RPPN “
Caminho
das
Pedras
”,
1000 m
,
15
o
10’2.5’’S
,
39
o
20’3’’W
,
24 September 2006
(fr.),
A.M.A.
Amorim
6387
(
CEPEC
!)
;
RPPN “Caminho das Pedras”,
936 m
,
15
o
10’2.7’’S
,
39
o
20’2.2’’W
,
26 November 2006
(fr.),
A.M.A. Amorim
6613
(
CEPEC
!).
Espírito Santo
: Mun. Cariacica,
Reserva Biológica de Duas Bocas
,
600 m
,
20
o
17’29’’S
,
40
o
31’10’’W
,
20 July 2008
(fl.),
A.M.A. Amorim
7577
(
RB
!). Mun. Santa Teresa,
8 August 2000
(fl.),
V. Demuner
1357
(
BHCB
!)
;
Estação Biológica de Santa Lúcia
,
22 September 1999
(fl.),
V.
Demuner
25
(
MBML
!)
;
Estação Biológica de Santa Lúcia
,
769 m
,
19
o
58’14.6’’S
,
40
o
32’13.3’’W
,
13 November 2011
(st.),
M.F.
Santos
733
(
SPF
!)
;
Reserva Biológica Augusto Ruschi
,
850 m
,
6 December 2001
(fr.),
L. Kollmann
5156
(
MBML
!)
;
Reserva Biológica Augusto Ruschi
,
28 November 2001
(fr.),
L. Kollmann
5048
(
MBML
!)
;
Reserva Biológica Augusto Ruschi
,
800 m
,
27 September 2011
(fl.),
L.
Kollmann
4776
(
MBML
!).
Minas Gerais
:
Mun. Bandeiras
,
830–850 m
,
15
o
48’23’’S
,
40
o
31’5’’W
,
30 January 2004
(fr.),
W.W.
Thomas
13637
(
BHCB
!)
.