Hohenbergia alba and Hohenbergia sparsiflora, two striking new bromeliads from the Brazilian Atlantic Forest
Author
Cavalcante, Brayan Paiva
Universidade de São Paulo (USP / CENA), 13416 - 903, Piracicaba, São Paulo, Brazil,
Author
Silva, Clécio Danilo Dias Da
Universidade Federal do Rio Grande do Norte (UFRN), 59078 - 900, Natal, Rio Grande do Norte,
Author
Souza, Everton Hilo De
Universidade Federal do Recôncavo da Bahia (UFRB), 44380 - 000, Cruz das Almas, Bahia, Brazil,
Author
Versieux, Leonardo M.
Universidade Federal do Rio Grande do Norte (UFRN), 59078 - 900, Natal, Rio Grande do Norte,
Author
Martinelli, Adriana Pinheiro
Universidade de São Paulo (USP / CENA), 13416 - 903, Piracicaba, São Paulo, Brazil,
text
Phytotaxa
2024
2024-09-24
665
3
233
242
https://doi.org/10.11646/phytotaxa.665.3.5
journal article
306652
10.11646/phytotaxa.665.3.5
784e7cb7-54e5-4df3-86f3-67b8ddc9c87c
1179-3163
14518747
Hohenbergia sparsiflora
B.P. Cavalcante, E.H. Souza & Versieux
,
sp. nov.
(
Figs. 3–4
)
Diagnosis
:
—
Hohenbergia sparsiflora
is closely related to
H. hatschbachii
, yet it can be readily distinguished by its infundibuliform rosette with sub-erect leaves (
vs.
broadly-crateriform with arcuate leaves), brownish leaves (
vs.
green), thinner peduncle (
1 cm
vs.
3 cm
diam.), inflorescence partially nested within the tank (
vs.
completely exposed), inconspicuously white-lanate and narrowly-pyramidal (
vs.
densely brown-lanate and wide-pyramidal); spikes sparsely organized (
vs.
dense organized), and floral bracts suborbicular with a mucronate apex (
vs.
triangular, apex acuminate), distinctly shorter than the sepal (
vs.
exceeding the sepal).
Type:—
BRAZIL
.
Bahia
. Una, Refugio de Vida Silvestre de Una, inside of the forest, near the research center of the park, ca.
123 m
.
elevation,
15°10’29.9”S
39°03’59.1”W
,
10 October 2018
,
E
.
H
. Souza &
B
.
P
. Cavalcante 28
(
Holotype
HURB
!,
UFRN
!).
Plant
epiphytic,
90–130 cm
tall when flowering, low formation of basal shoots, forming a infundibuliform tank of 35–45 ×
25–40 cm
.
Leaves
ca.
20 in
number, suberect to spreading;
leaf sheath
16–22 ×
20–24 cm
, broadly elliptic, either inconspicuously white lepidote to glabrous on both sides, dark castaneous except for the brownish to greenish distal part, stiffy and coriaceous, margins entire;
leaf blade
50–60 ×
19–24 cm
, brownish or pale-greenish, brownlepidote indument, linear-oblong to lingulate, apex brownish, acute or cuspidate, sub-erect spreading towards the apex, ending in a rigid and spinescent point
ca
.
3 cm
long, sparsely brownish-lepidote, with spinulose margins, marginal spines black, rigid, very close to each other.
Peduncle
25–40 cm
long,
ca
.
10 mm
diameter, erect, green, white lanate, covered and concealed by the peduncle bracts;
peduncle bracts
15–18 ×
1.5–1.9 cm
, lanceolate, with acuminate apex, pale-brown, imbricate, exceeding the internodes, glabrous or sparsely white-lepidote.
Inflorescence
30–45 cm
long,
30–45 cm
in diam. at the widest point, paniculate, narrowly-pyramidal, 3-branched at the base, once-branched in distal part, erect, sparsely white-lanate indument or glabrous;
primary bracts
resembling the peduncle bracts in shape and color, but smaller, 5.5–7 ×
2–2.2 cm
, shorter than the branches but exceeding the stipe;
primary branches
14–22 cm
long, stipes
2–5 cm
long, divergent to spreading, glabrous or sparsely white-lanate;
secondary bracts
ca
. 1 ×
1.5 cm
, triangular, apex acuminate, resembling the primary bracts in color but smaller, shorter than the branches but exceeding the stipe;
secondary branches
3–5 cm
long, short-stipitate or sessile, stipes (0–)
0.2–2.5 cm
long, flowers sparsely arranged along the rachis;
spikes
3–5 cm
long;
floral bracts
ca
. 2 ×
4 mm
, green, broadly triangular-ovate, convexly embracing the ovary, apex spinescent caudate, nerved, margins entire, green and blackish towards the apex, covered by a sparse white lanate indument, surpassing the ovary, and inferior than the sepals in length.
Flowers
16–19 mm
, sessile, odorless;
sepals
4–6 ×
5–8 mm
, green, broadly triangular-ovate, margins entire, apex mucronate, asymmetrical with a thin marginal wing that does not exceed the apex, glabrous;
petals
13–16 ×
4–6 mm
, linear-oblong base, the blade divergent to spreading, apex acute, margins entire, free, white at base and lilac blade, nerved, bearing 2 appendages;
petal appendages
fringed ornamentation.
Stamens
9–10 mm
, emerging from the the corolla;
filament
6–8 mm
, white, complanate and slightly dilated distally;
anther
ca
.
2 mm
long, apex apiculate;
ovary
4–6 ×
11 mm
, green, wide-ovoidal, placentation axial;
ovules
obtuse to caudate, with a prominent chalazal appendage;
style
12–14 mm
long, white, erect, surpassing the stamens, exposed by the divergent petal blades;
stigma
conduplicate-spiral.
Fruits
ca
. 14 × 16–
15 mm
, bluish when ripe;
seeds
ca
.
1 mm
long, sub-ellipsoidal, brownish.
FIGURE 3.
Hohenbergia sparsiflora
:
A.
Detail of a flowering plant.
B.
Leaf blade and acute or cuspidate apex, showing part of the sunked inflorescence.
C.
Peduncle, concealed by the imbricate peduncle bracts.
D.
Apical part of the inflorescence with open flowers and buds.
E.
Open flower. Bars:
A =
15 cm,
B =
10 cm,
C =
7 cm,
D =
1 cm,
E =
1 cm. Photos: B.P. Cavalcante.
FIGURE 4.
Hohenbergia sparsiflora
drawing.
A.
Flowering plant.
B.
Leaf apex.
C.
A primary branch showing secondary ones and the spaced distribution of the spikes/flowers.
D.
Flower with floral bract.
E.
Flower without the floral bract.
F.
Petal.
G.
Sepal.
H.
Floral bract. Bars:
A =
15 cm.
B =
5 cm.
C =
7 cm.
D -E =
3 mm.
F =
4 mm.
G =
2 mm.
H =
1 mm. Illustration by Brayan Paiva Cavalcante.
Etymology:
—
The specific epithet
“sparsiflora
” refers to the disposition of the flowers (“-flora”) in the spikes, which are sparsely arranged (“sparsus-”), creating a raceme-like pattern.
Distribution and habitat:
—
Hohenbergia sparsiflora
is an epiphyte growing in the densest and shadiest parts of the protected forest within the Natural Biological Station of Una (Reserva Biológica de Vida Silvestre de Una), located in the municipality of Una, state of
Bahia
, but also extending into neighboring areas. The species shares its habitat with several other
Hohenbergia
species.
Individual plants are scattered within the forest, typically growing on the highest branches of trees in shaded and areas with higher humidity. The area is a hotspot for
Hohenbergia
and also for
Bromelioideae
in general, hosting more than ten species within this fragment of the Atlantic Forest. These species include the closely related
H. hatschbachii
Leme (1999: 141)
, as well as
H. pabstii
Smith and Read (1976: 439)
,
H. belemii
Smith and Read (1976: 438)
,
H. blanchetii
,
H. brachycephala
Smith (1940: 129)
,
H. burle-marxii
,
H. capitata
Schulte & Schulte (1830:1252)
,
H. halutheriana
,
H. nidularioides
Cavalcante
et al.
(2021:200)
, and
H. stellata
.
Phenology:
—Blooming plants have been observed from August through December, with fruiting starting after November. Pre-flowering plants were observed in June. In cultivated plants, blooming was observed from September through December.
Conservation status:
—
This new species is restricted to the Una Natural Biological Station, which is a federal conservation unit. However, the conservation of the species faces challenges due to the expansion of roads, intensifying the edge effect and threatening these bromeliads. The assessment of known occurrences of this species reveals that the estimated extent of occurrence (EOO) covers
170.443 km
², which the area of occupancy (AOO) is
43.5 km
², leading to a classification of this species as Endangered (EN). Although the species is already protected by Brazilian federal laws within the reserve, we recommend a preliminarily classification of this species as Endangered EN B2b (i, ii, iii, iv), following the IUCN criteria guidelines (IUCN, 2020).
Observation:
—
Hohenbergia sparsiflora
is unique within the genus for the presence of loosely arranged spikes, which clearly distinguish it from other
Hohenbergia
species.
This new species is a member of the “giant
Hohenbergia
species
group” (
Cavalcante
et al.
2020
,
2021
b
, 2022,
Souza
et al.
2022b
). These species inhabit the coastal region of
Brazil
, especially within the Atlantic Forest domain of
Bahia
. While the rosette of this species shares similarities with other giant
Hohenbergia
species
, its sub-erect to arching leaves represents an unusual feature within the genus for this region. This characteristic facilitates a positive identification even when the plant is not in the flowering stage.
Hohenbergia sparsiflora
is morphologically similar to
H. hatschbachii
and both coexist in southern
Bahia
. This new species is easily distinguished by the sparsely arranged flowers along the rachis of the spikes, a partially sunken inflorescence in the rosette (
vs
. fully exposed), a sparsely white-lanate indumentum in inflorescence (
vs
. densely brown-lanate) and the small wide triangular floral bracts, not completely concealing the sepals (
vs
. prominent, triangular and concealing the sepals). Focusing solely on foliage, the brownish leaves (
vs
. green) is the easiest feature distinguishing
H. sparsiflora
and
H. hatschbachii
. Comparative measurements of herbarium specimens of related taxa are provided in
Table 1
.