Taxonomic monograph of Eugenia sect. Schizocalomyrtus (Myrtaceae: Myrteae), a group within Eugenia with unusual flowers
Author
Giaretta, Augusto
0000-0002-8263-9806
Faculdade de Ciências Biológicas e Ambientais, Universidade Federal da Grande Dourados, Unidade II, 79804 - 970, Caixa Postal 364, Dourados, MS, Brazil. https: // orcid. org / 0000 - 0002 - 8263 - 9806
Author
Lucas, Eve
0000-0002-7603-435X
Comparative Plant and Fungal Biology Department, Herbarium, Royal Botanic Gardens, Kew TW 9 3 AB Richmond, Surrey, United Kingdom. https: // orcid. org / 0000 - 0002 - 7603 - 435 X
Author
Sano, Paulo Takeo
0000-0002-1709-1215
Laboratório de Sistemática Vegetal, Universidade de São Paulo, Rua do Matão 14, Edifício Sobre as Ondas, 05508 - 090 São Paulo, Brazil. https: // orcid. org / 0000 - 0002 - 1709 - 1215
text
Phytotaxa
2021
2021-11-05
524
3
135
177
journal article
20904
10.11646/phytotaxa.524.3.1
83099003-0351-48b6-a5a3-c95778c7edfa
1179-3163
5649288
4.
Eugenia guanabarina
(Mattos & D.Legrand) Giaretta & M.C.Souza
(in
Giaretta
et al.
2018: 284
).
≡
Marlierea
guanabarina
Mattos & D.Legrand (in
Legrand & Mattos 1975: 6
).
Type
:—
BRAZIL
.
Rio de Janeiro
: Recreio do
Bandeirantes,
Pedra
de Itaúna
, fl., 22 [July] 1965,
N
. Santos 5967
(
holotype
: MVM [18113 herbarium number-photo!];
isotype: R). (
Figures 1F
,
11
).
=
Mitranthes langsdorffii
O.
Berg (1859: 595)
.
Chytraculia bergiana
Kuntze (1891: 238)
, non
Chytraculia langsdorffii
(O.Berg)
Kuntze (1891: 238)
.
Neomitranthes langsdorffii
(O.Berg)
Mattos (1981: 2)
, non
Eugenia langsdorffii
O.
Berg (1859: 568)
. Type:—
BRAZIL
.
Bahia
, fl., s.d.,
Blanchet 2309
(
lectotype
designated by
Giaretta
et al.
(2018)
: LE!; isolectotypes: F [69177 negative number-photo!], G! [00222536-2 sheets, 00222537-2 sheets], K! [000018787], NY [00405346-photo!], P! [00162722,
05232287
], W!). Remaining
syntype
:—
BRAZIL
.
Bahia
, ‘in silvis ad flumen Itahype prope Castel novo’, s.d.,
Riedel s.n.
(G! [00222538, 00222539-2 sheets], K! [000331517], LE! [6 sheets], M [0146829-photo!], MEL [666925-photo!], P! [
05232220
,
05232222
,
05232223
], W! [2 sheets]).
=
Calycorectes teixeireanus
Mattos (1996b: 1)
.
Eugenia teixeireana
(Mattos)
Mattos (2005: 9)
. Type:—
BRAZIL
.
Rio de Janeiro
, Barra da Tijuca, fl.,
13 July 1964
,
W. Hoehne 5759
(
holotype
: SP! [001302]; isotypes: FLOR, MBM! [herbarium number 69215], NY [00886386-photo!], UEC).
Shrubs or trees
2 to 13 m
tall. Young leaves with light-brownish trichomes
0.5–1 mm
long, appressed, moderately sparse abaxially, glabrate adaxially, glabrescent. Leaves with petioles 7–12 ×
1.5–2 mm
; blades 5–18 ×
2.5–7 cm
, elliptic or narrow-elliptic; base acute, cuneate or obtuse; apex acuminate,
0.5–3.5 cm
long, or narrowly acute, rare obtuse; midvein canaliculate adaxially; secondary veins 8–12 per side; marginal veins two, the innermost
1.5–3.5 mm
from the margin, the outermost
0.5–1 mm
from the margin. Inflorescence terminal or subterminal, thyrsoid; bract 1.5–2.5 ×
1–1.2 mm
, wide-ovate; rachis
5–80 mm
long; 1–4 pairs of lateral axes emerging from the rachis, lateral axes becoming shorter towards the apex,
5–40 mm
long, flattened, puberulent; each lateral axes with 3 to 7-flowered dichasial arrangement, middle flower sessile, lateral flowers with pedicels 3–10 ×
0.5 mm
; one rachis per axil, rarely two; bracteoles 1–2 ×
1–1.5 mm
, ovate or wide-ovate, puberulent, deciduous after anthesis. Flower buds 3–6 ×
2.5–4 mm
, obovate, calyx lobes fused and closed at the tip leaving an apiculum
0.3–1.5 mm
long, tearing transversely at the calyx base resulting in a structure calyptra-like,
3–5 mm
diameter, rare tearing irregularly in 3–4 lobes, puberulent, usually dense on hypanthium outside; petals (1) 4, 2.5–3.5 ×
3–4.5 mm
, obovate, sometimes irregular; stamens straight in the bud, filaments up to
6 mm
long, anthers
0.5–1 mm
long; staminal whorls flat,
3.5–5 mm
diameter, rounded, not tearing at anthesis; style
3–5 mm
long; ovary 2–locules, 3–5 ovules per locule. Fruits 12–14 ×
14–16 mm
, globose, atropurpureo when ripe, glabrous, often crowned by the remnant of the calyx calyptra-like; seeds 1–2.
Etymology:—
The specific epithet likely refers the
type
location of the Guanabara state, a previous name for
Rio de Janeiro state
used between 1960 and 1975.
Distribution and habitat:—
Eugenia guanabarina
is distributed in Southeastern (
Espírito Santo
and
Rio de Janeiro
) and Northeastern (
Bahia
)
Brazil
, often known from lowland coastal vegetation at elevations between
0 to 120 m
(
Figure 12
).
Eugenia guanabarina
is usually a small tree occurring in shrubby vegetation of
Restinga
, and also occurs as a tall tree in forest vegetation on non-marine sandy soil locally called
Muçununga
(
Peixoto
et al.
2008
), both within the Ombrophilous Dense Forest in the Atlantic forest.
Phenology:—
Flowers of
Eugenia guanabarina
have been mainly collected from July to November and less often from March to May, and fruiting from August to April (
Figure 6
).
Conservation status:—
Eugenia guanabarina
is known in seven protected areas (APA Lagoa Encantada, APA de Conceição da Barra, PES de Itaúnas, REBIO de Poço das Antas, REBIO de Una, RESEX Cassuruba, RPPN Reserva da Vale) and non-protected areas with broad EOO (
173,938.3 km
²). Although it is not threatened, human disturbance of coastal environments has a negative impact on natural populations. Thus, it is suggested that this species should be rated as Least Concern (LC).
Comments:—
Misleading taxonomy surrounding
Eugenia guanabarina
arose from the combination of a fused calyx in the bud usually opening via a calyptra-like structure and a thyrsoid inflorescence, features commonly associated with
Myrcia
s.l.
, and the embryo with fused cotyledons that suggests a relationship to Plinninae (sensu
Lucas
et al.
2007
) and
Eugenia
(
Souza 2009
)
.
Eugenia guanabarina
was previously accepted under
Neomitranthes
Kausel ex D.Legrand
(in
Legrand & Klein 1977: 671
) (
Mattos 1981
). However, phylogenetic reconstruction consistently recovered
E. guanabarina
within
Eugenia
(
Giaretta
et al.
2019b
)
, reinforced by straight stamens in the bud, in opposition to the strongly curved stamens in
Myrcia
s.l.
and the ‘
Plinia
group’ (
Vasconcelos
et al.
2015
). The combination of the thyrsoid inflorescence and buds tearing via calyptra-like structures are convenient characters to recognize
Eugenia guanabarina
. Alternatively, the thyrsoid can also be more depauperate in some collections. In such cases,
Eugenia guanabarina
can be confused with
E. acutata
but differs by the 8-12 secondary veins (
vs.
11-22), bracteoles ovate or wide-ovate (
vs.
lanceolate), flowers with staminal whorls rounded (
vs.
squared) and not tearing at anthesis (
vs.
slightly tearing), and fruit purplish when ripe (
vs.
yellowish).
Chytraculia bergiana
is a replacement name for
Mitranthes langsdorffii
, the earliest available basionym. However, the new combination is unavailable in
Eugenia
due to preexistence of
Eugenia bergiana
Grisebach (1860: 182)
. Thus,
Marlierea guanabarina
is the earliest name available to be combined (
Giaretta
et al.
2018
). Although the epithet has an improper Latin termination, the original spelling must be retained since it does not fit any conditional rule of the Code (see Art. 60).
Specimens examined:—
BRAZIL
.
Bahia
:
Arraial D’Ajuda
,
29 August 1961
, fl.,
A
.
P
.
Duarte
6058
(
K
!,
RB
!,
SPF
!);
Belmonte
,
27 September 1979
, fl.,
L
.
A
.
Mattos-Silva
614
(
CEPEC
!,
K
!,
RB
!);
Caravelas
,
9 October 2007
, fl.,
H
.
M
.
Dias
297
(
RB
!,
SPF
!,
VIES
!);
Mucuri
, s.d., fl.,
T
.
S
.
Santos
942
(
CEPEC
!);
Porto Seguro
,
25 August 1988
, fl.,
L
.
A
.
Mattos-Silva
2515
(
CEPEC
!,
K
!,
SP
!);
Una
,
10 September 2006
, es.,
M
.
C
.
Souza
385
(
RB
!),
28 February 1986
, fl.,
T
.
H
.
Brito
4066
(
CEPEC
!)
.
Espírito Santo
:
Conceição da Barra
,
25 July 1992
, fl.,
O
.
J
.
Pereira
3764
(
RB
!),
5 September 2011
, fl.,
A
.
Giaretta
1026
(
RB
!,
SPF
!,
VIES
!),
7 July 2012
, fl.,
L
.
F
.T.
Menezes
2042
(
VIES
!),
7 September 2011
, fl.,
A
.
Giaretta
1035
(
RB
!,
SPF
!,
VIES
!);
Linhares
,
27 August 1991
, fl.,
D.
A
.
Folli
1394
(
RB
!),
7 July 1983
, fl.,
D.
A
.
Folli
449
(
CEPEC
!,
RB
!);
São Mateus
,
31 January 2016
, fl. and fr.,
A
.
Giaretta
1629
(
SPF
!),
31 January 2016
, fl.,
A
.
Giaretta
1630
(
SPF
!)
.
Rio de Janeiro
:
Barra da Tijuca
,
10 September 1970
, fr.,
P
.
J
.
Fontella
424
(
MBM
!,
RB
!);
Maricá
,
11 May 2012
, fl.,
I
.
E
.
Santos
809
(
HB
!,
RB
!);
Recreio
dos
Bandeirantes
,
17 May 1964
, fl.,
N
.
Santos
5131
(
R
!),
9 August 1964
, fl.,
N
.
Santos
5201
(
R
!);
Rio de Janeiro
,
2 September 1969
, fl.,
D. Sucre
5905
(
RB
!,
SPF
!),
8 June 1973
, fl.,
E
.
A
.
Montalvo
100
(
RB
!);
Saquarema
,
12 February 1992
, fr.,
D.
S
.
D.
Araujo
9581
(
GUA
!,
RB
!),
29 March 2000
, fl. and fr.,
C
.
Farney
4036
(
RB
!,
SPF
!)
.