Yolanda Herrera-Arrieta

Instituto Politécnico Nacional, Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional, Unidad Durango, Sigma 119, Fracc. 20 de Noviembre II, 34220 Durango, Durango, Mexico.


Twelve years after publication of the floristic treatment “Las Gramíneas de Durango”, a list of accepted names is updated based on recent botanical work in Durango, Mexico. Ninety-one genera, 367 species, 15 subspecies, 55 varieties and 2 forms are included. Of these, 14 genera are newly recognized for Durango, whereas 17 genera previously reported from the state are now treated as synonyms, and three genera previously recorded are excluded. At the specific and infraspecific levels, 46 changes for synonymy occurred. Fifteen species were excluded, while 43 species and 27 infraspecific taxa were added. Four species are reported as new records for the state.

Key words: additions, Durango, grasses, Mexico.


Después de 12 años que fuera publicado el tratamiento florístico de “Las gramíneas de Durango” se presenta una relación de nombres aceptados, actualizados con base en trabajos botánicos recientes, de las gramíneas de Durango, México. Se reconocen un total de 91 géneros, 367 especies, 15 subespecies, 55 variedades y 2 formas. De ellos, 14 géneros representan nuevos registros para la entidad, mientras que 17 previamente reconocidos corresponden a sinónimos en el inventario actual y se excluyen tres registrados anteriormente. En los niveles específico e infraespecífico, se realizaron 46 cambios por sinonimia. Quince especies se excluyeron, mientras que 43 y 27 taxa infraespecíficos se adicionaron. Cuatro especies resultaron ser nuevos registros para el estado.

Palabras clave: adiciones, Durango, gramíneas, México.


Because of the great economic importance and large size of the family, the nomenclature of Poaceae is huge and elaborate. The first comprehensive treatment of grasses from North America was prepared by Beal (1896) and later Hitchcock (1913) prepared a treatment of Mexican grasses. In addition to making plant collections throughout the continent since the end of the 19th Century, American agrostologists continued to verify the identity of the taxa, as well as describe and apply names to new species. As a result of their efforts, a number of important floristic and floristic-ecologic reports from large regions have been published, e.g., North America (Hitchcock, 1935 and Hitchcock & Chase, 1951), “Nueva Galicia” (McVaugh, 1983), and “The grasslands of Durango” (Gentry, 1957). Most taxa have more than one name, because they were described by different authors, and some names have been repeatedly misapplied to different species. In both cases, valid names since have been established with the later names relegated to synonymy.

The first important catalogue of grasses in the New World was the “Index of American grasses”, edited by Chase and Niles (1962), who included all accepted names and synonymy known at the time. Another very recent compilation of this kind is the Catalogue of New World Grasses (Soreng et al. 2013,, continually updated) with hard copies published by subfamilies (Judziewicz et al. 2000, Peterson et al. 2001, Zuloaga et al. 2003, and Soreng et al. 2003, 2013). Dávila et al. (2006) compiled and edited the corresponding data of the accepted names and synonymy for the Mexican taxa in the “Catálogo de las Gramíneas de México”. The present article is based on these two last catalogues, and has been further enriched by recently published treatments (e.g., Finot et al. 2004, Bess et al. 2006, Zuloaga et al. 2007, Bell and Columbus 2008, Valdés-Reyna et al. 2009, Columbus and Smith 2010, Peterson et al. 2010, Chemisquy et al. 2010, Peterson et al. 2012) and/or additions of new described species (Finot et al. 2004, Peterson et al. 2004, 2006, Peterson and Columbus 2009). In addition, I have included new reports based on review of recently collected grass specimens in the state of Durango (Herrera Arrieta et al. 2004, Herrera Arrieta and Cortés Ortíz 2009, 2010, Herrera Arrieta et al. 2012).

In conjunction with projects that the Mexican Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO) has funded to pursue biodiversity research, I have found that there are substantial changes that should be reported to the community of agrostologists, grassland students, and general users. These include newly found taxa, new synonyms, and corrections to erroneous determinations. The purpose of the current study is to review these changes and provide an updated list of the names of the currently accepted taxa for Durango.


Grass specimens from Durango are constantly being deposited by scientists and students at the CIIDIR herbarium, and this material has been the source of new records during the past 12 years. In addition, other important herbaria with many Mexican collections were examined: CHAPA, ENCB, HUAA, IEB, MEXU, SLPM, TAES, US. Most of the synonyms and nomenclatural changes follow those given in the Catalogue of New World Grasses (Soreng et al. 2013, http: //


Tables 1 and 2 show the numerous modifications at the generic, specific or infraspecific level for grasses in Durango that have occurred during the last 12 years. Accepted taxa are displayed in bold.

In summary, an additional 15 genera are currently recognized as occurring in Durango (these indicated by * in Table 1 and 2), whereas 17 genera previously recognized for the state are now treated as synonyms (**Table 1). Three previously recorded genera are excluded: Allolepis Soderstr. & H.F. Decker, Guadua Kunth and Setariopsis Scribn. Guadua was based on an erroneous determination; Allolepis and Setariopsis were cited for Durango but a specimen was never found.

Forty-six changes due to synonymy occurred at the specific and infraspecific level (Table 1).

Table 1. Poaceae with nomenclatural changes. i) Species now considered synonyms of other species (either staying in the same genus or transferred to a different one). ii) Species for which the current recognized genus was segregated from another. iii) Species for which the previously recognized genus was synonymized under another. * New genera recognized as occurring in Durango. **Genera in synonymy.

Accepted name

Old name (synonym)

ii)*Achnatherum eminens (Cav.) Barkworth

**Stipa eminens Cav.

i) Arundinella hispida (Humb. & Bonpl. ex Willd.) Kuntze

Arundinella palmeri Vasey ex Beal

iii) Bouteloua dactyloides (Nutt.) Columbus

**Buchloë dactyloides (Nutt.) Engelm.

iii) Bouteloua reederorum Columbus

**Cyclostachya stolonifera (Scribn.) Reeder & Reeder

iii) Bouteloua polymorpha (E. Fourn.) Columbus

**Pentarrhaphis polymorpha (E. Fourn.) Griffiths

iii) Cenchrus clandestinus (Hochst. & Chiov.) Morrone

**Pennisetum clandestinum Hochst. & Chiov.

i) Cenchrus michoacanus H.F. Gut. & Morrone

Pennisetum crinitum (Kunth) Spreng.

i) Cenchrus spinifex Cav.

Cenchrus incertus M.A. Curtis

i) Cenchrus longisetus M.C. Johnst.

Pennisetum villosum R. Br. ex Fresen.

ii)*Chascolytrum subaristatum (Lam.) Desv.

**Briza subaristata Lam.

ii) Dinebra panicea subsp. mucronata (Michx.) P.M. Peterson & N. Snow

Leptochloa mucronata (Michx.) Kunth

ii)*Diplachne fusca subsp. fascicularis (Lam.) P.M. Peterson & N. Snow

Leptochloa fascicularis (Lam.) A. Gray

ii) Diplachne fusca subsp. uninervia (J. Presl) P.M. Peterson & N. Snow

Leptochloa uninervia (J. Presl) Hitchc. & Chase

ii)*Disakisperma dubium (Kunth) P.M. Peterson

Leptochloa dubia (Kunth) Nees & N. Snow

ii) Distichlis eludens (Soderstr. & H.F. Decker) H.L. Bell & Columbus

**Reederochloa eludens Soderstr. & H.F. Decker

ii) Elymus arizonicus (Scribn. & J.G. Sm.) Gould

Agropyron spicatum (Pursh) Scribn. var. arizonicum (Scribn. & J.G. Sm.) M.E. Jones

iii) Elymus elymoides (Raf.) Swezey

**Sitanion hystrix (Nutt.) J.G. Sm.

ii) Elymus repens (L.) Gould

**Agropyron repens (L.) P. Beauv.

ii) Elymus trachycaulus (Link) Gould ex Shinners

Agropyron trachycaulum (Link) Malte ex H.F. Lewis

ii)*Hopia obtusa (Kunth) Zuloaga & Morrone

Panicum obtusum Kunth

ii) Leptochloa crinita (Lag.) P.M. Peterson

Chloris crinita Lag & N. Snow

ii)*Megathyrsus maximus (Jacq.) B.K. Simon

Panicum maximum Jacq.& S.W.L. Jacobs

ii)*Melinis repens (Willd.) Zizka

**Rhynchelytrum repens (Willd.) C.E. Hubb.

ii)*Mnesithea granularis (L.) de Koning & Sosef

**Hackelochloa granularis (L.) Kuntze

iii) Muhlenbergia alopecuroides (Griseb.) P. M. Peterson & Columbus

**Lycurus setosus (Nutt.) Reeder

iii) Muhlenbergia biloba Hitchc.

**Bealia mexicana Scribn.

iii) Muhlenbergia cenchroides (Humb. & Bonpl. ex Willd.) P.M. Peterson

**Aegopogon cenchroides Humb. & Bonpl.ex Willd.

i) Muhlenbergia emersleyi Vasey

Muhlenbergia distans Swallen

iii) Muhlenbergia ligulata (E. Fourn.) Scribn. & Merr.

**Chaboissaea ligulata E. Fourn.

iii) Muhlenbergia pereilema P.M. Peterson

**Pereilema crinitum J. Presl

iii) Muhlenbergia phalaroides (Kunth) P.M. Peterson

Lycurus phalaroides Kunth

iii) Muhlenbergia phleoides (Kunth) Columbus

Lycurus phleoides Kunth

iii) Muhlenbergia shepherdii (Vasey) Swallen

**Blepharoneuron shepherdii (Vasey) P.M. Peterson & Annable

iii) Muhlenbergia subbiflora Hitchc.

Chaboissaea subbiflora (Hitchc.) Reeder & C. Reeder

iii) Muhlenbergia tricholepis (Torr.) Columbus

Blepharoneuron tricholepis (Torr.) Nash

iii) Muhlenbergia uniseta (Lag.) Columbus

Aegopogon tenellus (DC.) Trin.

i) Paspalum denticulatum Trin.

Paspalum lividum Trin. ex Schltdl.

ii)*Peyritschia deyeuxioides (Kunth) Finot

Trisetum deyeuxioides (Kunth) Kunth

ii)*Peyritschia pringlei (Scribn.) S.D. Koch

Trisetum kochianum Hern. Torres

i) Setaria pumila (Poir.) Roem. & Schult.

Setaria lutescens (Weigel ex Stuntz) F.T. Hubb.

ii)*Steinchisma cuprea (Hitchc. & Chase) W.V. Br.

Panicum cupreum Hitchc. & Chase

ii)*Torreyochloa pallida var. pauciflora (J. Presl) J.I. Davis

Glyceria pauciflora J. Presl

i) Trachypogon spicatus (L. f.) Kuntze

Trachypogon plumosus (Humb. & Bonpl. ex Willd.) Nees

i) Urochloa fusca (Sw.) B.F. Hansen & Wunderlin

Urochloa fasciculata Kunth

ii)*Zuloagaea bulbosa (Kunth) Bess

Panicum bulbosum Kunth

I excluded the following 15 species because they were based on misidentifications: Agrostis alba L. (synonym of Poa nemoralis L.), Allolepis texana (Vasey) Soderstr. & H.F. Decker, Aristida purpurea var. parishii (Hitchc.) Allred, Axonopus compressus (Sw.) P. Beauv., Bouteloua disticha (Kunth) Benth., Elymus interruptus Buckley, Eragrostis obtusiflora (E. Fourn.) Scribn., Festuca rubra L., Guadua longifolia (E. Fourn.) R.W. Pohl, Hordeum arizonicum Covas, Leptoloma cognata (Schult.) Chase, Panicum virgatum L., Setariopsis latiglumis (Vasey) Scribn., Sorghastrum brunneum Swallen, Urochloa texana (Buckley) R.D. Webster.

Forty-three species, 5 subspecies and 22 varieties were added to the previous treatment (Table 2).

Table 2. Additional taxa (species and infraspecific taxa) not reported in 2001. i = New records for Durango; ii = Recently described species not listed in Herrera Arrieta, 2001; iii = Reported in Herrera Arrieta et al., 2012; iv = Reported in Herrera Arrieta & Cortés Ortíz, 2010; v = excluded in 2001 but now confirmed to occur in the state.


Bothriochloa palmeri (Hack.) Pilg.


Bothriochloa perforata (Trin. ex E. Fourn.) Herter


Bothriochloa saccharoides (Sw.) Rydb.


Bothriochloa springfieldii (Gould) Parodi


Bouteloua rigidiseta (Steud.) Hitchc.


Cenchrus brownii Roem. & Schult.


Cenchrus longispinus (Hack.) Fernald


Calamagrostis divaricata P.M. Peterson & Soreng


Digitaria pubiflora (Vasey) Wipff.


Dinebra panicea (Retz.) P.M. Peterson & N. Snow


Diplachne fusca (L.) P. Beauv. ex Roem. & Schult.


Elymus canadensis L.


Eragrostis barrelieri Daveau


Eragrostis curvula (Schrad.) Nees


Eragrostis erosa Scribn. ex Beal


Eragrostis pringlei Mattei


Eriochloa contracta Hitchc.


Festuca arizonica Vasey


*Hesperostipa neomexicana (Thurb.) Barkworth


Hordeum jubatum L.


Leptochloa pluriflora (E. Fourn.) P.M. Peterson & N. Snow


Luziola fluitans (Michx.) Terrell & H. Rob.


Muhlenbergia filiculmis Vasey


Muhlenbergia longiglumis Vasey


Muhlenbergia mucronata (Kunth) Trin.


Muhlenbergia plumbea (Trin.) Hitchc.


Muhlenbergia stricta (J. Presl) Kunth


Muhlenbergia torreyi (Kunth) Hitchc. ex Bush


Muhlenbergia villiflora Hitchc.


Paspalum dilatatum Poir.


Paspalum jaliscanum Chase


Piptochaetium pringlei (Beal) Parodi


Poa matri-occidentalis P.M. Peterson & Soreng


Sorghastrum nudipes Nash


Sporobolus contractus Hitchc.


Sporobolus spiciformis Swallen


Steinchisma hians (Elliott) Nash


Tridens albescens (Vasey) Wooton & Standl.


Trisetum durangense Finot & P.M. Peterson


Trisetum martha-gonzaleziae P.M. Peterson & Finot


Trisetum palmeri Hitchc.


Trisetum spicatum (L.) K. Richt.


Urochloa discifera (E. Fourn.) Morrone & Zuloaga



Distichlis spicata subsp. stricta (Torr.) Thorne


Dinebra panicea subsp. brachiata (Steud.) P.M. Peterson & N. Snow


Elymus elymoides subsp. brevifolius (J.G. Sm.) Barkworth


Paspalum dilatatum Poir. subsp. dilatatum


Poa matri-occidentalis P.M. Peterson & Soreng subsp. matri-occidentalis



Aristida schiedeana Trin. & Rupr. var. schiedeana


Aristida ternipes var. gentilis (Henrard) Allred


Aristida ternipes Cav. var. ternipes


Bothriochloa laguroides var. laguroides (DC.) Herter


Bothriochloa saccharoides (Sw.) Rydb. var. saccharoides


Dichanthelium sphaerocarpon (Elliott) Gould var. sphaerocarpon


Distichlis spicata var. mexicana Beetle


Echinochloa crusgalli (L.) P. Beauv. var. crusgalli


Echinochloa crusgalli var. zelayensis (Kunth) Hitchc.


Echinochloa crus-pavonis (Kunth) Schult. var. crus-pavonis


Echinochloa muricata var. microstachya Wiegand


Elymus canadensis L. var. canadensis


Eragrostis pectinacea var. miserrima (E. Fourn.) Reeder


Eragrostis pectinacea (Michx.) Nees var. pectinacea


Glyceria striata (Lam.) Hitchc. var. striata


Gouinia virgata (J. Presl) Scribn. var. virgata


Muhlenbergia villiflora Hitchc. var. villiflora


Oplismenus burmannii (Retz.) P. Beauv. var. burmannii


Oplismenus burmannii var. nudicaulis (Vasey) McVaugh


Panicum alatum Zuloaga & Morrone var. alatum


Trisetum filifolium var. aristatum Scribn. ex Beal


Vulpia myuros var. hirsuta Hack.


The final result is the recognition of 91 genera, 367 species, 15 subspecies, 55 varieties and 2 forms (listed in Appendix below); it is worth mentioning that four species (Digitaria pubiflora, Elymus canadensis, Luziola fluitans, and Paspalum dilatatum) are new records for Durango.


I thank the Instituto Politécnico Nacional (SIP, COFAA) for facilities and financial support carried out at IPN CIIDIR Durango, in the framework of the project “Pastos más comunes en Durango” SIP-20031025; and CONABIO for financial support to the projects R010 y V024. I also recognize and thank the time dedicated to the revision of this manuscript by anonymous reviewers and by S. González and P.M. Peterson, whose recommendations substantially improved the present manuscript. Many thanks are given to my colleagues for the help at the herbarium CIIDIR.


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Recibido en junio de 2012.

Aceptado en junio de 2013.


Updated list of Poaceae in Durango, Mexico

Achnatherum eminens (Cav.) Barkworth

Agrostis exarata Trin.

A. liebmannii (E. Fourn.) Hitchc.

A. perennans (Walter) Tuck.

A. rosei Scribn. & Merr.

A. scabra Willd.

A. tolucensis Kunth

Andropogon gerardii Vitman

A. glomeratus var. pumilus (Vasey) Vasey

A. pringlei Scribn. & Merr.

Anthoxanthum odoratum L.

Aristida adscensionis L.

A. appressa Vasey

A. arizonica Vasey

A. divaricata Humb. & Bonpl. ex Willd.

A. eludens Allred & Valdés-Reyna

A. gibbosa (Nees) Kunth

A. havardii Vasey

A. laxa Cav. var. laxa

A. pansa Wooton & Standl. fo. pansa

A. purpurea var. nealleyi (Vasey) Allred

A. purpurea Nutt. var. purpurea

A. schiedeana var. orcuttiana (Vasey) Allred & Valdés-Reyna

A. schiedeana Trin. & Rupr. var. schiedeana

A. scribneriana Hitchc.

A. spanospicula Allred, Valdés-Reyna & Sánchez-Ken

A. ternipes var. gentilis (Henrard) Allred

A. ternipes Cav. var. ternipes

Arundinella hispida (Humb. & Bonpl. ex Willd.) Kuntze

Arundo donax L. fo. donax

Avena fatua L.

A. sativa L.

Axonopus mexicanus G.A. Black

Bothriochloa alta (Hitchc.) Henrard

B. barbinodis (Lag.) Herter

B. laguroides (DC.) Herter var. laguroides

B. palmeri (Hack.) Pilg.

B. perforata (Trin. ex E. Fourn.) Herter

B. saccharoides (Sw.) Rydb. var. saccharoides

B. springfieldii (Gould) Parodi

B. wrightii (Hack.) Henrard

Bouteloua aristidoides (Kunth) Griseb. var. aristidoides

B. barbata Lag. var. barbata

B. chondrosioides (Kunth) Benth. & S. Watson

B. curtipendula var. caespitosa Gould & Kapadia

B. curtipendula (Michx.) Torr. var. curtipendula

B. curtipendula var. tenuis Gould & Kapadia

B. dactyloides (Nutt.) Columbus

B. gracilis (Kunth) Lag. ex Griffiths

B. hirsuta var. glandulosa (Cerv.) Gould

B. hirsuta Lag. var. hirsuta

B. parryi var. gentryi (Gould) Gould

B. parryi (E. Fourn.) Griffiths var. parryi

B. polymorpha (E. Fourn.) Columbus

B. radicosa (E. Fourn.) Griffiths

B. ramosa Scribn. ex Vasey

B. reederorum Columbus

B. repens (Kunth) Scribn.

B. rigidiseta (Steud.) Hitchc.

B. scorpioides Lag.

B. simplex Lag.

B. uniflora var. coahuilensis Gould & Kapadia

Brachypodium mexicanum (Roem. & Schult.) Link var. mexicanum

Bromus anomalus Rupr. ex E. Fourn.

B. carinatus var. californicus Shear

B. catharticus Vahl var. catharticus

B. mucroglumis Wagon

B. porteri (J.M. Coult.) Nash

B. richardsonii Link

B. thysanoglottis Soderstr. & Beaman

Calamagrostis divaricata P.M. Peterson & Soreng

C. pringlei Scribn. ex Beal

C. valida Sohns

Cenchrus brownii Roem. & Schult.

C. ciliaris L.

C. clandestinus (Hochst. ex Chiov.) Morrone

C. echinatus L.

C. longispinus (Hack.) Fernald

C. michoacanus H.F. Gut. & Morrone

C. multiflorus J. Presl

C. myosuroides Kunth var. myosuroides

C. spinifex Cav.

C. villosus (R. Br. ex Fresen.) Kuntze

Chascolytrum subaristatum (Lam.) Desv.

Chloris gayana Kunth

C. rufescens Lag.

C. submutica Kunth

C. virgata Sw.

Cortaderia selloana (Schult. & Schult. f.) Asch. & Graebn.

Cottea pappophoroides Kunth

Cynodon dactylon (L.) Pers.

C. plectostachyus (K. Schum.) Pilg.

Dactyloctenium aegyptium (L.) Willd.

Dasyochloa pulchella (Kunth) Willd. ex Rydb.

Deschampsia flexuosa (L.) Trin.

Dichanthelium sphaerocarpon (Elliott) Gould var. sphaerocarpon

Digitaria californica (Benth.) Henrard var. californica

D. ciliaris (Retz.) Koeler

D. filiformis (L.) Koeler

D. insularis (L.) Fedde

D. panicea (Sw.) Urb.

D. pubiflora (Vasey) Wipff.

D. sanguinalis (L.) Scop.

D. ternata (Hochst. ex A. Rich.) Stapf

Dinebra panicea ssp. brachiata (Steud.) P.M. Peterson & N. Snow

D. panicea ssp. mucronata (Michx.) P.M. Peterson & N. Snow

Diplachne fusca ssp. fascicularis (Lam.) P.M. Peterson & N. Snow

D. fusca ssp. uninervia (J. Presl) P.M. Peterson & N. Snow

Disakisperma dubium (Kunth) P.M. Peterson & N. Snow

Distichlis eludens (Soderstr. & H.F. Decker) H.L. Bell & Columbus

D. spicata var. mexicana Beetle

D. spicata ssp. stricta (Torr.) Thorne

Echinochloa colona (L.) Link

E. crusgalli (L.) P. Beauv. var. crusgalli

E. crusgalli var. zelayensis (Kunth) Hitchc.

E. crus-pavonis (Kunth) Schult. var. crus-pavonis

E. holciformis (Kunth) Chase

E. muricata var. microstachya Wiegand

E. oplismenoides (E. Fourn.) Hitchc.

E. polystachya (Kunth) Hitchc. var. polystachya

Eleusine indica (L.) Gaertn.

E. multiflora Hochst. ex A. Rich.

Elionurus barbiculmis Hack.

E. tripsacoides Humb. & Bonpl. ex Willd.

Elymus arizonicus (Scribn. & J.G. Sm.) Gould

E. canadensis L. var. canadensis

E. elymoides ssp. brevifolius (J.G. Sm.) Barkworth

E. repens (L.) Gould ssp. repens

E. riparius Wiegand

E. trachycaulus (Link) Gould ex Shinners ssp. trachycaulus

Enneapogon desvauxii P. Beauv.

Eragrostis barrelieri Daveau

E. cilianensis (All.) Vignolo ex Janch.

E. ciliaris (L.) R. Br. var. ciliaris

E. curvula (Schrad.) Nees

E. erosa Scribn. ex Beal

E. glandulosa L.H. Harv.

E. intermedia Hitchc. var. intermedia

E. lehmanniana Nees

E. lugens Nees

E. maypurensis (Kunth) Steud.

E. mexicana (Hornem.) Link ssp. mexicana

E. palmeri S. Watson

E. pectinacea var. miserrima (E. Fourn.) Reeder

E. pectinacea (Michx.) Nees var. pectinacea

E. pilosa (L.) P. Beauv.

E. pringlei Mattei

E. viscosa (Retz.) Trin.

Eriochloa acuminata (J. Presl) Kunth var. acuminata

E. aristata Vasey var. aristata

E. contracta Hitchc.

E. lemmonii Vasey & Scribn.

E. nelsonii Scribn. & J.G. Sm.

Erioneuron avenaceum (Kunth) Tateoka var. avenaceum

E. nealleyi (Vasey) Tateoka

Festuca amplissima Rupr.

F. arizonica Vasey

F. breviglumis Swallen

F. pringlei St. Yves

F. rosei Piper

F. tolucensis Kunth

Glyceria fluitans (L.) R. Br.

G. striata (Lam.) Hitchc. var. striata

Gouinia virgata (J. Presl) Scribn. var. virgata

Hesperostipa neomexicana (Thurb.) Barkworth

Heteropogon contortus (L.) P. Beauv. ex Roem. & Schult.

H. melanocarpus (Elliott) Benth.

Hilaria belangeri (Steud.) Nash var. belangeri

H. cenchroides Kunth

H. mutica (Buckley) Benth.

H. swallenii Cory

Hopia obtusa (Kunth) Zuloaga & Morrone

Hordeum jubatum L.

Hyparrhenia rufa (Nees) Stapf

Koeleria pyramidata (Lam.) P. Beauv.

Lasiacis nigra Davidse

L. procerrima (Hack.) Hitchc.

L. ruscifolia (Kunth) Hitchc.

Leersia hexandra Sw.

Leptochloa crinita (Lag.) P.M. Peterson & N. Snow

L. pluriflora (E. Fourn.) P.M. Peterson & N. Snow

Lolium multiflorum Lam.

L. perenne L.

Luziola fluitans (Michx.) Terrell & H. Rob.

Megathyrsus maximus (Jacq.) B.K. Simon & S.W.L. Jacobs

Melinis repens (Willd.) Zizka

Microchloa kunthii Desv.

Mnesithea granularis (L.) de Koning & Sosef

Muhlenbergia alamosae Vasey

M. alopecuroides (Griseb.) P.M. Peterson & Columbus

M. annua (Vasey) Swallen

M. arenicola Buckley

M. arizonica Scribn.

M. asperifolia (Nees & Meyen ex Trin.) Parodi

M. biloba Hitchc.

M. brevifolia Scribn. ex Beal

M. brevis C.O. Goodd.

M. brevivaginata Swallen

M. cenchroides (Humb. & Bonpl. ex Willd.) P.M. Peterson

M. ciliata (Kunth) Trin.

M. crispiseta Hitchc.

M. depauperata Scribn.

M. diversiglumis Trin.

M. dubia E. Fourn.

M. dumosa Scribn. ex Beal

M. durangensis Y. Herrera

M. eludens C. Reeder

M. emersleyi Vasey

M. eriophylla Swallen

M. filiculmis Vasey

M. filiformis (Thurb. ex S. Watson) Rydb.

M. flavida Vasey

M. flaviseta Scribn.

M. fragilis Swallen

M. gigantea (E. Fourn.) Hitchc.

M. glauca (Nees) B.D. Jacks.

M. implicata (Kunth) Trin.

M. ligulata (E. Fourn.) Scribn. & Merr.

M. longiglumis Vasey

M. longiligula Hitchc.

M. macroura (Kunth) Hitchc.

M. michisensis Y. Herrera & P.M. Peterson

M. microsperma (DC.) Kunth

M. minutissima (Steud.) Swallen

M. montana (Nutt.) Hitchc.

M. mucronata (Kunth) Trin.

M. palmeri Vasey

M. pauciflora Buckley

M. pectinata C.O. Goodd.

M. pereilema P.M. Peterson

M. peruviana (P. Beauv.) Steud.

M. phalaroides (Kunth) P.M. Peterson

M. phleoides (Kunth) Columbus

M. plumbea (Trin.) Hitchc.

M. polycaulis Scribn.

M. porteri Scribn. ex Beal

M. pubescens (Kunth) Hitchc.

M. quadridentata (Kunth) Trin.

M. ramulosa (Kunth) Swallen

M. reederorum Soderstr.

M. repens (J. Presl) Hitchc.

M. richardsonis (Trin.) Rydb.

M. rigens (Benth.) Hitchc.

M. rigida (Kunth) Trin.

M. robusta (E. Fourn.) Hitchc.

M. scoparia Vasey

M. setifolia Vasey

M. shepherdii (Vasey) Swallen

M. speciosa Vasey

M. stricta (J. Presl) Kunth

M. strictior Scribn. ex Beal

M. subaristata Swallen

M. subbiflora Hitchc.

M. tenella (Kunth) Trin.

M. tenuifolia (Kunth) Kunth

M. texana Buckley

M. torreyi (Kunth) Hitchc. ex Bush

M. tricholepis (Torr.) Columbus

M. uniseta (Lag.) Columbus

M. utilis (Torr.) Hitchc.

M. vaginata Swallen

M. villiflora Hitchc. var. villiflora

M. virescens (Kunth) Trin.

M. virletii (E. Fourn.) Soderstr.

Nassella leucotricha (Trin. & Rupr.) R.W. Pohl

N. mucronata (Kunth) R.W. Pohl

N. tenuissima (Trin.) Barkworth

Oplismenus burmannii (Retz.) P. Beauv. var. burmannii

O. burmannii var. nudicaulis (Vasey) McVaugh

O. compositus (L.) P. Beauv.

Otatea acuminata ssp. aztecorum (McClure & E.W. Sm.) R. Guzmán, Anaya & Santana

O. fimbriata Soderstr.

Panicum alatum Zuloaga & Morrone var. alatum

P. antidotale Retz.

P. decolorans Kunth

P. dichotomiflorum Michx.

P. hallii Vasey var. hallii

P. hirticaule var. verrucosum Zuloaga & Morrone

P. lepidulum Hitchc. & Chase

P. parcum Hitchc. & Chase

P. plenum Hitchc. & Chase

P. stramineum Hitchc. & Chase

P. trichoides Sw.

P. vaseyanum Scribn. ex Beal

Pappophorum bicolor E. Fourn.

P. vaginatum Buckley

Paspalum conjugatum P.J. Bergius

P. convexum Humb. & Bonpl. ex Flüggé

P. crinitum Chase

P. denticulatum Trin.

P. dilatatum Poir. ssp. dilatatum

P. distichum L.

P. humboldtianum Flüggé

P. jaliscanum Chase

P. notatum Flüggé

P. plicatulum Michx.

P. prostratum Scribn. & Merr.

P. pubiflorum Rupr. ex E. Fourn.

Peyritschia deyeuxioides (Kunth) Finot

P. pringlei (Scribn.) S.D. Koch

Phalaris canariensis L.

Phragmites australis (Cav.) Trin. ex Steud.

Piptochaetium brevicalyx ssp. flexuosum Barkworth

P. fimbriatum (Kunth) Hitchc.

P. pringlei (Beal) Parodi

P. virescens (Kunth) Parodi

Poa annua L.

P. matri-occidentalis P.M. Peterson & Soreng ssp. matri-occidentalis

P. strictiramea Hitchc.

Polypogon elongatus Kunth

P. interruptus Kunth

P. monspeliensis (L.) Desf.

P. viridis (Gouan) Breistr.

Rhipidocladum racemiflorum (Steud.) McClure

Schizachyrium cirratum (Hack.) Wooton & Standl.

S. sanguineum (Retz.) Alston

S. scoparium var. neomexicanum (Nash) Hitchc.

S. tenerum Nees

Scleropogon brevifolius Phil.

Setaria adhaerens (Forssk.) Chiov.

S. grisebachii E. Fourn.

S. latifolia (Scribn.) R.A.W. Herrm.

S. leucopila (Scribn. & Merr.) K. Schum.

S. liebmannii E. Fourn.

S. macrostachya Kunth

S. parviflora (Poir) Kerguélen

S. pumila (Poir.) Roem. & Schult.

S. scheelei (Steud.) Hitchc.

S. verticillata (L.) P. Beauv.

S. viridis (L.) P. Beauv.

Sorghastrum nudipes Nash

S. nutans (L.) Nash

Sorghum bicolor (L.) Moench

S. halepense (L.) Pers.

Sphenopholis obtusata (Michx.) Scribn.

Sporobolus airoides (Torr.) Torr. var. airoides

S. atrovirens (Kunth) Kunth

S. coahuilensis Valdés-Reyna

S. contractus Hitchc.

S. cryptandrus (Torr.) A. Gray

S. indicus (L.) R. Br. var. indicus

S. macrospermus Scribn. ex Beal

S. palmeri Scribn.

S. pyramidatus (Lam.) Hitchc.

S. spiciformis Swallen

S. trichodes Hitchc.

S. wrightii Munro ex Scribn.

Steinchisma cuprea (Hitchc. & Chase) W.V. Br.

S. hians (Elliott) Nash

Torreyochloa pallida var. pauciflora (J. Presl) J.I. Davis

Trachypogon spicatus (L. f.) Kuntze

Tragus berteronianus Schult.

Tridens albescens (Vasey) Wooton & Standl.

T. muticus (Torr.) Nash

Tripogon spicatus (Nees) Ekman

Tripsacum dactyloides (L.) L. var. dactyloides

T. lanceolatum Rupr. ex E. Fourn.

T. pilosum Scribn. & Merr.

T. zopilotense Hern.-Xol. & Randolph

Trisetum durangense Finot & P.M. Peterson

T. filifolium var. aristatum Scribn. ex Beal

T. irazuense (Kuntze) Hitchc.

T. martha-gonzaleziae P.M. Peterson & Finot

T. palmeri Hitchc.

T. spicatum (L.) K. Richt.

T. viride (Kunth) Kunth

T. virletii E. Fourn.

Tristachya laxa Scribn. & Merr.

Triticum aestivum L.

Urochloa arizonica (Scribn. & Merr.) Morrone & Zuloaga

U. discifera (E. Fourn.) Morrone & Zuloaga

U. fusca (Sw.) B.F. Hansen & Wunderlin

U. meziana (Hitchc.) Morrone & Zuloaga

U. plantaginea (Link) R.D. Webster

Vulpia microstachys (Nutt.) Munro

V. myuros var. hirsuta Hack.

V. octoflora (Walter) Rydb.

Zea mays L. ssp. mays

Z. mays ssp. mexicana (Schrad.) H.H. Iltis

Zuloagaea bulbosa (Kunth) Bess