Taxonomic revision of Muhlenbergia (Poaceae, Chloridoideae, Cynodonteae, Muhlenbergiinae) in Central America: phylogeny and classification
Author
Peterson, Paul M.
https://orcid.org/0000-0001-9405-5528
Department of Botany MRC- 166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013 - 7012, USA
peterson@si.edu
Author
Herrera Arrieta, Yolanda
https://orcid.org/0000-0003-3814-6518
Instituto Politecnico Nacional, CIIDIR Unidad-Durango-COFAA, Durango, C. P. 34220, Mexico
Author
Lobo Cabezas, Silvia
https://orcid.org/0009-0007-8100-2559
Herbario Nacional, Museo Nacional de Costa Rica, Apartado Postal 749 - 1000, San Jose, Costa Rica
Author
Romaschenko, Konstantin
https://orcid.org/0000-0002-7248-4193
Department of Botany MRC- 166, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013 - 7012, USA
text
PhytoKeys
2023
2023-08-03
230
1
106
http://dx.doi.org/10.3897/phytokeys.230.103882
journal article
http://dx.doi.org/10.3897/phytokeys.230.103882
1314-2003-230-1
365B97AE96F45DB295043BF02F4AF4BE
8.
Muhlenbergia diversiglumis Trin.,
Mem
. Acad. Imp. Sci.
Saint-Petersbourg
,
Ser
. 6, Sci. Math., Seconde Pt. Sci. Nat. 6,4(3-4):298. 1841.
Fig. 8A-D
Type
.
Mexico
, Porto Pedro,
Karwinsky 1393
(
lectotype
, designated here
: LE-TRIN-1497.01!; isolectotypes: LE-TRIN-1497.02!, LE-TRIN-1497.03!, US-84831 fragm. ex LE-TRIN!, W-0002564!).
Description.
Sprawling
annuals
.
Culms
16-50 cm tall, decumbent, rooting at the lower nodes;
nodes
retrorsely pilose;
internodes
smooth or scabridulous.
Leaf
s
heaths
1.5-8.5 cm long, sparsely or densely pilose, hairs to 3 mm long, papillose-based;
ligules
0.5-0.8 mm long, membranous, apex truncate, erose;
blades
2-6 cm long, 1.5-4 mm wide, flat, bases distinctly narrowed to the junction with the sheath, surfaces scabridulous and sparsely pilose, hairs papillose-based.
Panicles
6-10.5 cm long, 2.0-4.5 cm wide, open;
primary branches
0.8-3.5 cm long, secund, spreading at right angles or somewhat reflexed usually lying to one side with 2-5 spikelets;
secondary branches
not developed;
pedicels
1-5 mm long, scabrous or shortly pilose, hairs papillose-based;
disarticulation
at the base of the primary branches where there is a weak and contorted stipe.
Spikelets
4-8 mm long, dimorphic with respect to the glumes, proximal spikelets on each branch almost sessile;
glumes
of proximal
spikelets
on each branch subequal, 0.2-0.7 mm long, orbicular, truncate, often erose or irregularly toothed, unawned;
glumes
of distal
spikelets
on each branch markedly unequal;
lower glumes
to 8 mm long, 1-veined, acute, usually awned, awns 0.5-3 mm;
upper glumes
orbicular, acute, sometimes awn-tipped;
lemmas
4.0-7.6 mm long, linear to broadly lanceolate, light greenish, smooth or scabrous, usually with greenish veins, apices acuminate, awned, awns 6-19 mm long, usually straight, scabrous;
paleas
3.7-6.8 mm long, narrowly lanceolate, coarsely papillate or almost smooth, 2-keeled, the veins prominent, scabrous, greenish, sometimes extending as minute awns, acuminate;
anthers
0.4-0.8 mm long, yellowish.
Caryopses
1.8-3 mm long, oblong-ovoid, flattened, brownish. 2
n
= 20.
Figure 8.
A-D
Muhlenbergia diversiglumis
Trin.
A
habit
B
floret
C
glumes
D
ligule
E-H
Muhlenbergia implicata
(Kunth) Kunth
E
habit
F
floret
G
glumes
H
ligule.
A-D
drawn from
P.M. Peterson & C.R. Annable 4158
(US, WS).
E-H
drawn from
P.M. Peterson & C.R. Annable 4598
(US, WS).
Distribution.
The species is native to North America, Central America, Colombia, Venezuela, Ecuador, Peru, and Argentina (
Peterson and Annable 1991
;
Peterson et al. 2001
).
Ecology.
Muhlenbergia diversiglumis
grows on moist cliffs, along water courses, sandy slopes, and road cuts, primarily in moist shaded environments of broadleaf evergreen forests and pine-oak forests; 600-2500 m.
Comments.
Muhlenbergia diversiglumis
can be differentiated from
M. ciliata
,
M. microsperma
, and
M. romaschenkoi
in having secund panicles (versus not secund in the latter three species) with each primary branch consisting of 2-5 dimorphic spikelets where the proximal spikelets have short orbicular glumes less than 1 mm long, and the distal spikelets have glumes up to 8 mm long (
Peterson and Annable 1991
;
Giraldo-Canas
and Peterson 2009
).
Muhlenbergia diversiglumis
is a member of
M. subg. Muhlenbergia
and is sister to
M. alamosae
Vasey, a species from
Mexico
(
Peterson et al. 2021
).
Specimens examined.
Costa Rica
.
Alajuela
:
1 km
S of Carrizal,
R.W. Pohl & G. Davidse 11500
(
US
).
Cartago
: San
Ramon
, E of San
Jose
, open grassy roadside,
R.W. Pohl & Mark Gabel 13678
(MO); Road crossing of
Rio
Reventado between Llano Grande and Tierra Blanca, gravelly river banks,
R.W. Pohl & M. Lucas 13092
(MO).
Heredia
: Porrosati,
2 km
by road N of Porrosati,
R.W. Pohl & M. Gabel 13672
(MO); Carrizal,
H. Pittier 786
(
US
); Barba, cultures a La Esmeralda,
A. Tonduz 1692
(
US
).
Puntarenas
: Cordillera de
Tilaran
,
W. Haber & W. Zuchowski 10891
(MO, INB).
San
Jose
: Aserri, Cuenca del Pirris-Damas, Cerros Caraigres, Falda S, Quebrada Concha, en el camino viejo a Bijagual,
J.F. Morales 5913
(MO, INB);
Leon
Cortes
Castro, Z.P. Caraigres, Cuenca del Pirris-Damas, Fila El Alto.
J.F. Morales 5933
(MO, INB),
Perez
Zeledon
, P. N.
Chirripo
camino a
Chirripo
a orilla del sendero, Cuenca
Terraba-
Sierpe,
E. Alfaro
,
et al. 966
(CR, INB); Hacienda La Esperanza, La Palma,
O.
Jimenez
963
(CR). San Francisco de
Guadalupe
, cultivos,
O.
Jimenez
s.n.
(
US
); Jardines de San Francisco de
Guadalupe
,
H. Pittier 9068
(
US
);
11 km
N of San Isidro de El General along the Carretera Interamericana,
R.W. Pohl & G. Davidse 11570
(
US
); Between
Aserri
and Tarbaca,
P.C. Standley 41352
(
US
); vicinity of Santa
Maria
de Dota, moist forest,
P.C. Standley 41831
(
US
); vicinity of Santa
Maria
de Dota,
P.C. Standley & J. Valerio 43215
(
US
); La Verbena de Alajuelita,
A. Tonduz 9084
(
US
).
El Salvador
.
Ahuachapan
: Parque Nacional El Imposible: San Benito, al S del enganche de los
rios
Venado y Escalares,
E. Sandoval & F.
Perez
1470
(MO).
San Salvador
:
Volcan
San Salvador, el Boqueron, disturbed secondary forest bordering pasture and cafetale,
A. Monro et al. 2179
(MO); Volcano of San Salvador,
A.S. Hitchcock 8929
(
US
); Volcano of San Salvador,
A.S. Hitchcock 8939
(
US
); Volcano of San Salvador,
A.S. Hitchcock 8940
(
US
).
Guatemala
.
Alta Verapaz
: near San
Cristobal
Verapaz, wet thickets and second growth forest,
L.O. Williams et al. 42228
(MO); Coban,
H. Von Turckheim s.c.
(
US
); Coban, Maisfeldem. unter Kiefernald,
H. Von Turckheim 3988
(
US
).
Guatemala
: Guatemala City,
A.S. Hitchcock 9049
(
US
).
Huehuetenango
:
21 mi
NW of Huehuetenango on Pan American Hwy. 1,
P.M. Peterson & C.R. Annable 4682
(MO).
Jalapa
: Mountains along the road between Jalapa and Paraiso,
P.C. Standley 77358
(
US
).
Jutiapa
: Volcan Chingo,
W.C. Shannon 3699
(
US
).
Quiche
: Chichicastenango,
4 km
S of Chichicastenango, steep wooded hillside dominated by pine and oak,
W.E. Harmon 4613
(MO).
San Marcos
: Wet mountain forest near Aldea Fraternidad, between San Rafael Pie de la Cuesta and Palo GPoales, west facing slope of the Sierra Madre Mountains,
L.O. Williams et al. 25993; L.O. Williams et al. 25971
(
US
); Montane cloud forest area on outer slopes of Tajumulco Volcano, Sierra Madre Mountains about
8-10 km
west of San Marcos,
L.O. Williams et al. 26928
(
US
).
Honduras
.
Francisco
Morazan
: Tatumbla, Cerro Uyuca,
R.W. Pohl 12493
(MO); San Antonio del Oriente,
J.R. Swallen 10975
(
US
); forest with with
Pinus
and
Liquidambar
entre
Pena
Blanca y Lo de Ponce,
L.O. Williams & A. Molina R. 17126
(
US
).
Mexico
.
Chiapas
. Angel Albino Corzo
: slopes of
Rio
Cuxtepec. along stream below Finca Cuxtepec,
D.E. Breedlove & J.L. Strother 46692
(CAS, MO).
Motozintla
: Sierra Madre de Chiapas
5 mi
NW of Motozintla de Mendoza on road to El Porvenir,
P.M. Peterson & C.R. Annable 4707
(ENCB, MEXU,
US
, MO); W side of Cerro Mozotal,
11 km
NW of the junction of the road to Motozintla along the road to El Porvenir and Siltepec,
D.E. Breedlove & B.M. Bartholomew 55714
(CAS, MO).
Zinancantan
: Hwy
190, 10 mi
SE of the road to Simojovel paraje of Granadia,
D.E. Breedlove 7276
(ENCB).