New species and combinations in Meniscium (Thelypteridaceae)
Author
Fernandes, Rozijane Santos
Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Botânica, Caixa Postal 486, 30123 - 970, Belo Horizonte, Minas Gerais, Brazil
Author
Yesilyurt, Jovita Cislinski
Department of Life Sciences, The Natural History Museum, Cromwell Rd, SW 7 5 BD London, UK
Author
Salino, Alexandre
Universidade Federal de Minas Gerais, Instituto de Ciências Biológicas, Departamento de Botânica, Caixa Postal 486, 30123 - 970, Belo Horizonte, Minas Gerais, Brazil
text
Phytotaxa
2014
2014-10-29
184
1
1
11
http://dx.doi.org/10.11646/phytotaxa.184.1.1
journal article
10.11646/phytotaxa.184.1.1
1179-3163
5153177
Meniscium triangularis
R.S.Fernandes & Salino
sp. nov.
(Figures 2A–D; 3B; 5C–D)
Meniscium triangularis
is similar to
M. cocleanum
,
M. reticulatum (
Linnaeus 1759: 1325
)
Swartz (1803: 274)
and
M. membranaceum (
Mettenius 1859: 22
)
Pichi Sermolli (1968: 180)
by the presence of buds in axils of pinnae and having triangular-lanceolate pinnae. It differs from these species mainly by the presence of the dense indument of scales and trichomes on the abaxial surface of the lamina, appressed trichomes on the main veins and costae, asymmetric pinna bases, round sori, and glands on the sporangia.
Type:—
COLOMBIA
.
Antioquia
:
Anorí
,
Vereda Santa Gertrudis
, finca
La Estrella
, entre las quebradas
Santa Gertrudis
y Rivas.
07°07’46.3”N
,
75°09’31.4”W
,
1315 m
,
2 October 2003
.
W
.
D. Rodríguez
et al. 4115,
(
holotype
HUA142183
[basal portion] +
HUA 142184
[a distal portion], isotypes
COL
,
NY
)
.
Plants terrestrial. Rhizomes unknown. Fronds probably monomorphic (sterile specimen not seen). Fertile fronds
124– 158 cm
long; petioles
63–88 cm
long,
4.7 mm
in diameter at base, brown at the base and stramineous to greenish further up, pubescent with slightly appressed, tortuous trichomes,
0.2 mm
long; laminae
61–70 cm
long, 1-pinnate, elliptic to oblong, chartaceous. Rachises sinuate, pubescent, abaxial side glabrous or spreading trichomes, adaxial surface with acicular, curved trichomes
0.2–0.3 mm
long and spreading scales mostly 0.4–1.4 ×
0.05–0.10 mm
with two or more lateral cell ranks, irregular, filiform to lanceolate, basifix and appressed, caducous. Buds present in axils of distal pinnae. Aerophores present at pinna bases. Pinnae 10–11 pairs, 14–15 × 2.0–
2.3 cm
, lateral pinnae lanceolate to narrow-triangular, usually sessile or stalked to
5 mm
in proximal pair, bases asymmetric with acroscopic sides excavate to truncate and parallel to rachis and basiscopic sides rounded to short-lobed, proximal pinnae with cuneate base, margins entire to undulate, slightly crenate near the apex, with appressed trichomes, apex acute to acuminate; adaxial surface pubescent only at costae with scattered acicular, curved to appressed trichomes (
0.1 mm
long), abaxial surface of costae and veins tomentose with a white appearance, trichomes dense, acicular, ciliform, appressed
0.3– 0.5 mm
long, scales appressed, caducous, 0.4–1.4 ×
0.05–0.1 mm
, filiform to lanceolate, or with irregular forms, sometimes with long ciliate margins; laminar surface between the veins glabrous or with sparse, small, appressed, capitate trichomes (
0.08–0.10 mm
long with two cells); venation regularly anastomosing, forming 6–9 of areoles between costa and pinna margin, ca. 7–10 veins arising from costae of fertile pinnae per
3 cm
; cross-veins straight to slightly arcuate, uniting at an obtuse angle (145°), giving rise to a free excurrent veinlet, these veinlets occasionally bisecting the areole. Sori round, on the cross-veins, not confluent at maturity, trichomes present on the receptacle between sporangia; sporangia with globose caducous glands on the capsule. Spores monolete, ellipsoidal, perispore echinulate with sparse stelae.
FIGURE
. Scanning electron micrograph (
SEM
) of sporangia.
A
.
Meniscium divergens
sporangium with acicular trichomes (
T
.
W
. Henkel et al. 4368,
NY
).
B
.
Meniscium triangularis
sporangium with globose gland (
W
. D. Rodríguez et al. 4115,
NY
). Scale bars:
A
,
B
= 100 μm.
Distribution and habitat:—
Meniscium triangularis
is known only from the
type
locality in
Colombia
where it grows in secondary forest at
1315 m
.
Etymology:—
The epithet refers to the shape of lateral pinnae.
Notes:—
Meniscium triangularis
is well characterized by features that have not been commonly mentioned in the past, such as the presence of scales on the abaxial surface of the lamina (Fig. 2D). The species is also distinguished by the presence of the buds on axils of distal pinnae (Fig. 2A), a character that is also found in
M. cocleanum
. However,
M. cocleanum
has a glabrous abaxial laminar surface, oblong sori, and glabrous sporangia, while
M. triangularis
has scales and appressed trichomes on the main veins and costae, round sori and glandular sporangia (Fig. 3B).
Meniscium triangularis
and
M. reticulatum
have the same triangular–lanceolate pinna outline. However,
Meniscium triangularis
can be distinguished by having buds in the axils of distal pinnae, abaxial surface of costae and veins tomentose with trichomes and scales, trichomes
0.3–0.5 mm
long, acicular, ciliform, dense, appressed, which gives a white aspect to the costae; conspicuous scales 0.4–1.4 ×
0.05–0.10 mm
, appressed, caducous, with irregular forms, with long-ciliate margin, sori rounded (Fig. 2A–D), and sporangia capsule with globose, caducous glands (Fig. 3B). Conversely,
M. reticulatum
lacks buds on the axils of basal pinnae or buds, has the abaxial surface of costae and veins with curved, acicular trichomes,
0.1–0.2 mm
long, slightly to moderately dense, scales usually lacking or rare, filiform or shapeless and margin not ciliate, sori oblong, and sporangia glabrous.
Meniscium membranaceum
has an indument of trichomes and scales on costae and veins similar to that of
M. triangularis
,
from which it differs by having only 2–4 pinnae pairs, with 19–20 areole rows between costa and pinna margin, buds in the axils of basal pinnae and straight secondary veins forming a 180° angle.
FIGURE
. Scanning electron micrograph (SEM) of spores.
A
,
B
:
Meniscium cocleanum
spores with winged surface.
C
,
D
:
M. divergens
with echinulate surface with low, dense echinulae.
E
,
F
:
M. nesioticum
with cristate-reticulate surface. (A–B from
Salino et al. 15361,
BHCB; C–D from
T.W. Henkel et al. 4368,
NY; E–F from
G.C. Aymard 5331,
UC). Scale bars: A, C, E = 10 µm; B, D, F = 5 µm.
Meniscium membranaceum
and
M. triangularis
have echinulate spores, however,
M. triangularis
has sparse stelae forming clumps (Fig. 5C–D), while
M. membranaceum
has stelae with perforations (Fig. 5A–B).
Meniscium reticulatum
has cristate–reticulate spores, confirming the statements of
Wood (1973)
and
Tryon & Tryon (1982)
.
FIGURE
. Scanning electron micrograph (SEM) of spores.
A
,
B
:
Meniscium membranaceum
spores with echinulate surface with stelae with perforations;
C
,
D
:
M. triangularis
spores with echinulate surface with sparse stelae forming clumps;
E
,
F
:
M. reticulantum
spores with cristate-reticulate surface. (A, B from
A. Salino 15015,
BHCB; C, D from
W. D. Rodríguez et al. 4115
NY; E, F from
Ranker & Lamieux 1665,
UC). Scale bars: A, C =10 µm; B, D = 5 µm; E, F =100 µm.