Appendix lists the 340 species whose distribution is restricted to a single quadrat, with their threatened status indicated when applicable.

Rzedowski (1993) pointed out that the distribution of areas with endemic species for the flora of Mexico does not coincide with the distribution of biodiversity. He indicated that the endemic taxa are concentrated in areas of dry climate and this conclusion was reached based on species richness alone, without taking the historical element into account. The latter has been included in this paper by identifying areas of endemism shared by at least two monophyletic groups. Our results indicate that majority of the areas: the northeastern rosette scrub, the gypsum grasslands, the Sierra Gorda, the southern portion of the Chihuahuan Desert, the area of Tehuacán-Cuicatlán, the Sierra de Quila, the western area of the Balsas River Basin, the Tehuantepec area and the Central Depression of Chiapas, have a dry climate, corroborating Rzedowski’s hypothesis. The endemic groups occur at low to middle elevations, in xeric vegetation. The only area with a tropical climate and a high weighted endemism index is El Triunfo in Chiapas, and El Salto in Durango has a temperate climate.

The Sierra Gorda was previously recognized as an area with significant endemism and it is included in the Mexican System of Natural Protected Areas, the SINAP (Arriaga-Cabrera et al., 2000). Additionally, the Tehuacán-Cuicatlán area is comprised of arid vegetation and is perhaps the most important biosphere reserve in Mexico (Arriaga-Cabrera et al., 2000). It is a floristic province, and an ecological island given the high number of endemics, estimated at 365 species (Méndez-Larios et al., 2004; Dávila et al., 2002).

The area of Metztitlán-Tolantongo was previously known for having high endemism and it was decreed as a biological reserve in 2000 (Hiriart-Valencia & González-Medrano, 1983; Arriaga-Cabrera et al., 2000). Furthermore, Sierra de Quila was earlier identified as a hotspot for conservation based on mammal distributional predictions as biodiversity surrogates (Sánchez-Cordero et al., 2005). In addition, the semiarid gypsum karstlands in north central Mexico characterized by a mosaic of shrubby communities and endemic gypsophile grasslands were formerly acknowledged as areas with elevated endemism and important to preserve (Henrickson & Johnston, 1986; Meyer et al., 1992; Huerta-Martínez & García-Moya, 2004).

The western area of the Balsas River Basin in Michoacán, Guerrero, Morelos and State of Mexico, is another region with high indices of endemism. Rodríguez-Jiménez et al. (2005) have identified 337 endemic species of vascular plants in this biogeographic province. Cañón del Zopilote and Infiernillo are two proposed areas for conservation in this province (Arriaga-Cabrera et al., 2000), yet they represent only a small area within the Balsas River Basin.

Several regions in Nuevo León harbor extremely large numbers of endemisms in the Cactaceae (Juárez et al., 2009), and a high concentration of narrowly distributed Asteraceae (González-Zamora et al., 2007; Alanís-Flores et al., 2011). Moreover, these regions coincided with one of the areas of high endemism identified in this study: the Northeastern rosette scrub.

Our results detected the Sierra La Laguna in Baja California Sur as a territory with high endemism. Plant diversity and endemism on the entire Baja California Peninsula have previously attracted attention (Riemann & Ezcurra, 2007). The notable endemism in the Sierra La Laguna, Baja California, had also been pointed out (León de la Luz & Breceda, 2006) and resulted in the Sierra La Laguna reserve being decreed one of Mexico’s biosphere reserves (Arriaga-Cabrera et al., 2000).

El Triunfo is a biosphere reserve with elevated endemism and richness, for which approximately 1000 species of vascular plants have been reported. The area includes several habitats such as cloud, oak and tropical forest (Martínez-Meléndez et al., 2008; Pérez-Farrera et al., 2012). It was decreed as a reserve because it is considered to be a Pleistocene refugium for several tropical species (Arriaga-Cabrerra et al., 2000). As well, the pine and oak forests in El Salto have provided suitable habitats for several gymnosperm relict species (Valenzuela-Núñez & Granados-Sánchez, 2009).

The Central Depression of Chiapas has been earlier identified as an area with seasonally dry tropical forests and tropical oak forests where approximately 3.4% of the total number of vascular plant species in Mexico are distributed (Reyes-García & Sousa, 1997). Furthermore, among the habitats of Tehuantepec, the tropical dry forests harbor the largest diversity including several taxa of endemic angiosperm (Acosta et al., 2003; Pérez-García et al., 2010).

It is noteworthy that the majority of the areas with the highest endemism indices, such as El Salto (Durango), the Central Depression of Chiapas, Tehuantepec, (Oaxaca), and Tolantongo in the southern area of the Chihuahuan Desert are not protected under the SINAP scheme (Arriaga-Cabrera et al., 2000).

Microendemic species

It is crucial to take the rarity of species into account when setting conservation priorities (Mooers & Redding, 2009). It has been mentioned that in areas of endemism the species with restricted distributions are usually on the red lists (e.g., Argentina, Szumik et al., in press). The same happens in Mexico where we found that a large number of the species whose distribution is restricted to a single quadrat in our study area are included on the Mexican List of Threatened Species (Anonymous, 2010).

Most of the species on this list with a limited distribution are cacti. More than 900 species of Cactaceae are present throughout Mexico (Ortega-Baes & Godínez-Álvarez, 2006). This is one of the groups that are most used as ornamental plants and so have been continuously extracted from their habitats, with the result that they are now the most threatened group in Mexico (Gómez-Hinostrosa & Hernández, 2000; Hernández & Gómez-Hinostrosa, 2011a,b).

CONCLUSIONS

Future research should examine the probable causes of diversification for the angiosperm lineages in the areas of endemism in Mega-Mexico. For other areas with high degrees of endemism, such as the Andes, isolation caused diversification, similar in many respects to the floras of remote oceanic islands (Särkinem et al., in press) or along elevational gradients (Kessler, 2000). Climate was the factor that promoted speciation in Australia’s areas of endemism (Ladiges et al., 2011), while tectonic stability in central and southern China influenced the permanence of areas of plant endemism (López-Pujol et al., 2011). In Sub-Saharan Africa, elevation range and low seasonality were core environmental predictors for centers of endemism (Jetz et al., 2004). Diversification in hotspots of biodiversity and endemism in Brazil were attributed to the effect of fire on vegetation (Simon et al., 2009), while serpentine soils and a benign climate favored endemism in California (Anacker & Harrison, in press).

Our results suggest that various causes promoted the diversification of several groups of plants in the areas of endemism, and a dry climate together with isolation are probably the most remarkable. Nine areas of endemism have a dry climate. Furthermore, the Central Depression of Chiapas and the Balsas River Basin are two areas that remained isolated, bordered by mountain ranges. In contrast, El Triunfo in Chiapas probably acted as a refugium for angiosperm lineages that remained there throughout the Pleistocene. Gypsum soils probably favored endemism in the northeastern rosette scrub and the grasslands of San Luis Potosí. However investigation is needed to corroborate these hypotheses.

It should be emphasized that hotspots do not necessarily coincide with species richness, the degree of threat or areas of endemism (Orme et al., 2005). The areas of endemism identified in our study do not coincide with the areas with elevated diversity of the flora of Mexico, as Rzedowski (1993) pointed out, and some of the areas of endemism in the Chihuahuan Desert, Balsas River Basin and the southern area of Oaxaca are not sufficiently protected.

ACKNOWLEDGEMENTS

We are grateful to Patricia Dávila and Jorge Meave del Castillo for their useful comments that improved the manuscript. We are grateful to Manuel Cuéllar and Ismael G. Valdivieso for their help designing the database, and to Rosario Landgrave for her invaluable help producing the maps, as well as to Manuel Cuéllar and Diego Angulo. Jerzy Rzedowski provided important information on the endemism of the Mexican flora; Carolina Calviño provided information on Apiaceae (Eryngium), Etelvina Gándara on Asparagaceae (Milla clade) and Scrophulariaceae (Leucophyllum); John Bain, Jose Panero, Edward Schilling and José Luis Villaseñor on Asteraceae; Salvador Arias and Héctor Hernández on Cactaceae; Mark Simmonds on Celastraceae; Pablo Carrillo Reyes and Raúl Acevedo-Rosas on Crassulaceae; Rafael Lira on Cucurbitaceae; Eduardo Estrada, Lourdes Rico and Jenny Sotuyo on Fabaceae; Susana Valencia on Fagaceae; Paul Peterson, María Elena Siqueiros and J. Travis Columbus on Poaceae; Rafael Fernández Nava on Rhamnaceae and Lynn Boss and Aarón Rodríguez on Solanaceae.

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Recibido en abril de 2012.

Aceptado en junio de 2012.

APPENDIX

Microendemic species of the Mexican lineages of angiosperms. These are restricted to a single quadrat. Species that are on the Mexican Red List (Anonymous, 2010) are indicated with the following designations in parentheses: A = threatened, P = endangered, Pr = under special protection.

Acanthaceae

Gypsacanthus nelsonii E.J. Lott, V. Jaram. & Rzed.

Holographis anisophylla T.F. Daniel

Holographis argyrea (Leonard) T.F. Daniel (Pr)

Holographis caput-medusae T.F. Daniel

Holographis hintonii (Leonard) T.F. Daniel

Holographis pallida Leonard & Gentry

Holographis tamaulipica T.F. Daniel

Holographis tolantongensis T.F. Daniel

Ixtlania acicularis M.E. Jones

Mexacanthus mcvaughii T.F. Daniel

Mirandea andradenia T.F. Daniel

Mirandea huastecensis T.F. Daniel

Mirandea hyssopus (Nees) T.F. Daniel

Ruellia conzattii Standl.

Ruellia guerrerensis T.F. Daniel

Ruellia laslobasensis E.A. Tripp

Ruellia sarukhaniana Ramamoorthy

Ruellia sororia Standl.

Achariaceae

Chiangiodendron mexicanum T. Wendt

Achatocarpaceae

Phaulothamnus spinescens A. Gray

Amaryllidaceae

Sprekelia clintiae Traub

Anacardiaceae

Pseudosmodingium andrieuxii Engl.

Apiaceae

Eryngium humile Cav.

Eryngium mexicanum S. Watson

Apocynaceae

Thenardia gonoloboides Woodson

Asparagaceae

Beaucarnea purpusii Rose

Beschorneria tubiflora Kunth (Pr)

Dasylirion inerme S. Watson

Hemiphylacus mahindae L. Hern.

Hemiphylacus novogalicianus L. Hern.

Jaimehintonia gypsophila B.L. Turner

Milla magnifica H.E. Moore

Milla rosea H.E. Moore

Nolina humilis S. Watson

Nolina lindheimeriana S. Watson

Nolina pliabilis (Baker) Lundell

Nolina pumila Rose

Yucca baccata Torr.

Yucca capensis L.W. Lenz

Asteraceae

Ageratum albidum (DC.) Hemsl.

Ageratum conyzoides L.

Ageratum maritimum Kunth

Ageratum microcephalum Hemsl.

Ageratum munaense R.M. King & H. Rob.

Ageratum paleaceum (Gay ex DC.) Hemsl.

Ageratum tomentosum (Benth.) Hemsl.

Alomia hintonii R.M. King & H. Rob.

Alvordia angusta S.F. Blake

Amauria carterae A.M. Powell

Arnicastrum glandulosum Greenm.

Axiniphyllum pinnatisectum (Paul G. Wilson) B.L. Turner

Axiniphyllum sagittalobum B.L. Turner

Axiniphyllum tomentosum Benth.

Baeriopsis guadalupensis J.T. Howell

Bahiopsis carterae (E.E. Schill.) E.E. Schill. & Panero

Bahiopsis chenopodina (Greene) E.E. Schill. & Panero

Bahiopsis laciniata (A. Gray) E.E. Schill. & Panero

Bahiopsis lanata Kellogg

Bahiopsis tomentosa (A. Gray) E.E. Schill. & Panero

Brickellia adenolepis (B.L. Rob.) Shinners

Brickellia adontophylla A. Gray

Brickellia amblyoleopsis (B.L. Rob.) R.M. King & H. Rob.

Brickellia aramberrana B.L. Turner

Brickellia cardiophylla B.L. Rob.

Brickellia coahuilensis (A. Gray) Harc. & Beaman

Brickellia floribunda A. Gray

Brickellia frutescens A. Gray

Brickellia glabrata (Rose) B.L. Rob.

Brickellia glutinosa A. Gray

Brickellia hastata Benth.

Brickellia hebercarpa (DC.) A. Gray

Brickellia kellermanii Greenm.

Brickellia pedunculosa (DC.) Harc. & Beaman

Brickellia peninsularis Brandegee

Brickellia rusbyi A. Gray

Brickellia simplex A. Gray

Brickellia urolepis S.F. Blake

Brickellia vernicosa B.L. Rob.

Brickellia wislizeni A. Gray

Calanticaria brevifolia (Greenm.) E.E. Schill. & Panero

Conoclinium mayfieldii T.F. Patterson

Correllia montana A.M. Powell

Eryngiophyllum pinnatisectum Paul G. Wilson

Eryngiophyllum rosei Greenm.

Eupatoriastrum triangulare (DC.) B.L. Rob.

Faxonia pusilla Brandegee

Gonzalezia hypargyrea (Greenm.) E.E. Schill. & Panero

Gonzalezia rosei (Greenm.) E.E. Schill. & Panero

Gymnolaena serratifolia Rydb.

Gymnolomia scaposa Brandegee

Henricksonia mexicana B.L. Turner

Hofmeisteria gayleana B.L. Turner

Hybridella anthemidifolia (B.L. Rob. & Greenm.) Olsen

Hydropectis aquatica Rydb.

Jaliscoa goldmanii (B.L. Rob.) R.M. King & H. Rob.

Jaliscoa paleacea (Cronquist) R.M. King & H. Rob.

Jaliscoa pappifera S.F. Blake

Jefea gnaphalioides (A. Gray) Strother

Jefea pringlei (Greenm.) Strother

Lundellianthus breedlovei (B.L. Turner) Strother

Lundellianthus guatemalensis (Donn. Sm.) Strother

Lundellianthus salvinii (Hemsl.) Strother

Marshalljohnstonia gypsophila Henrickson

Mexerion sarmentosum (Klatt) G.L. Nesom

Nesomia chiapensis B.L. Turner

Otopappus acuminatus S. Watson

Otopappus pittieri (Greenm.) B.L. Turner

Paneroa stachyofolia (B.L. Rob.) E.E. Schill.

Perymenium ovalifolium (A. Gray) B.L. Turner

Philactis zinnioides Schrad.

Pittocaulon bombycophole (Bullock) H. Rob. & Brettell

Pleurocoronis gentryi (Wiggins) R.M. King & H. Rob.

Pleurocoronis pluriseta (A. Gray) R.M. King & H. Rob.

Psacaliopsis purpusii (Greenm. ex Brandegee) H. Rob. & Brettell

Psacalium brachycomum (S.F. Blake) H. Rob. & Brettell

Psacalium calvum (Brandegee) Pippen

Psacalium decompositum (A. Gray) H. Rob. & Brettell

Psacalium globosum (B.L. Rob. & Fernald) H. Rob. & Brettell

Psacalium hintonii (Pippen) H. Rob. & Brettell

Psacalium hintoniorum B.L. Turner

Psacalium pachyphyllum (Sch. Bip.) Rydb.

Psacalium paucicapitatum (B.L. Rob. & Greenm.) H. Rob. & Brettell

Psacalium peltigerum (B.L. Rob. & Seaton) Rydb.

Psacalium radulifolium (Kunth) H. Rob. & Brettell

Psacalium tussilaginoides (Kunth) H. Rob. & Brettell

Robinsonecio porphyresthes (T.M. Barkley) T.M. Barkley & Janovec

Squamopappus skutchii (S.F. Blake) R.K. Jansen, N.A. Harriman & Urbatsch

Sidneya tenuifolia (A. Gray) E.E. Schill. & Panero

Stenocarpha ritovegana B.L. Turner

Stephanodoria tomentella Greene

Stevia chilapensis Soejima & Yahara

Stevia coahuilensis Soejima & Yahara

Stevia crassifolia Soejima & Yahara

Stevia ecatepecana Soejima, Yahara & K. Watan.

Stevia filodecaballoana Soejima, Yahara & K. Watan.

Stevia mascotensis Soejima & Yahara

Stevia mexicana Soejima, Yahara & K. Watan.

Stevia oaxacana Soejima & Yahara

Stevia oligophylla Soejima & Yahara

Stevia potosina Soejima, Yahara & K. Watan.

Stevia rotundifolia Soejima, Yahara & K. Watan.

Stevia scabrelloides Soejima & Yahara

Stevia viejoana Soejima, Yahara & K. Watan.

Steviopsis adenosperma (Sch. Bip.) B.L. Turner

Steviopsis amblyolepis (B.L. Rob.) R.M. King & H. Rob.

Steviopsis nesomii B.L. Turner

Steviopsis squamulosa (A. Gray) B.L. Turner

Steviopsis vigintiseta (DC.) R.M. King & H. Rob.

Stuessya apiculata (S.F. Blake) B.L. Turner & F.G. Davies

Stuessya perennans B.L. Turner & F.G. Davies

Tetrachyron chimalapanum B.L. Turner

Tetrachyron grayi (Klatt) Wussow & Urbatsch

Tetrachyron orizabensis (Klatt) Wussow & Urbatsch

Tuxtla pittieri (Greenm.) Villaseñor & Strother

Wamalchitamia appressipila (S.F. Blake) Strother

Wamalchitamia aurantiaca (Klatt) Strother

Wamalchitamia dionysi Strother

Zexmenia virgulta Klatt

Boraginaceae

Lasiarrhenum confundum B.L. Turner

Lashiarrhenum pinetorum I.M. Johnst.

Mimophytum omphalodoides Greenm.

Brassicaceae

Lexarzanthe mexicana (Iltis & Al-Shehbaz) Diego & Calderón

Raphanorhyncha crassa Rollins

Burseraceae

Beiselia mexicana Forman

Bursera rzedowskii C.A. Toledo

Cactaceae

Astrophytum asterias Lem. (P)

Aztekium hintonii (Glass & W.A. Fitz Maur.) (Pr)

Aztekium ritteri Boed. (A)

Cumarinia odorata (Boed.) Buxb. (Pr)

Geohintonia mexicana Glass & W.A. Fitz Maur. (Pr)

Leuchtenbergia principis Hook. (A)

Neobuxbaumia multiareolata (Daws.) Bravo, Scheinvar & Sánchez-Mej.

Obregonia denegrii Frič & A. Berger (A)

Pachycereus tepamo S. Gama-López & S. Arias

Pelecyphora aselliformis Ehrenb. (Pr)

Pelecyphora strobiliformis (Werderm.) Frič & Schelle ex Kreuz. (A)

Thelocactus hastifer (Werderm. & Boed.) F.M. Knuth (A)

Turbinicarpus alonsoi Glass & S. Arias

Turbinicarpus hoferi Lüthy & A.B. Lau (A)

Turbinicarpus lophophoroides (Werderm.) Buxb. & Backeb. (Pr)

Turbinicarpus pseudopectinatus (Backeb.) Glass & R.A. Foster (Pr)

Caryophyllaceae

Cerdia virescens Moc. & Sessé

Convolvulaceae

Ipomoea decemcornuta O’Donell

Crassulaceae

Cremnophila linguifolia (Lem.) Moran

Cremnophila nutans (Rose) Rose

Graptopetalum amethystinum E. Walther

Graptopetalum bartramii Rose

Pachyphytum amethystinum Rose

Pachyphytum brachetii J. Reyes, O. González & A. Gut.

Pachyphytum brevifolium Rose

Pachyphytum caesium Kimnach & Moran

Pachyphytum coeruleum J. Meyrán

Pachyphytum contrerasii Pérez-Calix, I. García & Cházaro

Pachyphytum fittkaui Moran

Pachyphytum garciae Pérez-Calix & Glass

Pachyphytum hookeri A. Berger

Pachyphytum kimnachii Moran

Pachyphytum longifolium Rose

Pachyphytum machucae I. García, Glass & Cházaro

Pachyphytum oviferum J.A. Purpus

Pachyphytum rzedowskii I. García, Pérez-Calix & J. Meyrán

Pachyphytum saltense Brachet, J. Reyes & Mondragón

Pachyphytum werdermannii Poelln.

Thompsonella garcia-mendozae P. Carrillo & Pérez-Calix

Thompsonella mixtecana J. Reyes & L. López

Thompsonella spathulata Kimnach

Thompsonella xochipalensis M. Gual Diaz, S. Peralta & Pérez-Calix

Crossosomataceae

Velascoa recondita Calderón & Rzed.

Cucurbitaceae

Cucurbita fraterna L.H. Bailey

Cucurbita pedatifolia L.H. Bailey

Apatzingania arachoidea I.M. Johnston

Vaseyanthus brandegeei Rose

Cyperaceae

Cypringlea evadens (C.D. Adams) Reznicek & S. González

Euphorbiaceae

Euphorbia coalcomanensis (Croizat) V.W. Steinm. (A)

Euphorbia cyri V.W. Steinm. (E)

Euphorbia dressleri V.W. Steinm. (E)

Euphorbia finkii (Boiss.) V.W. Steinm. (A)

Euphorbia peritropoides (Millsp.) V.W. Steinm.

Euphorbia personata (Croizat) V.W. Steinm.

Euphorbia tehuacana (Brandegee) V.W. Steinm. (A)

Euphorbia tithymaloides L.

Fabaceae

Acaciella barrancana (Gentry) L. Rico

Acaciella goldmanii Britton & Rose

Acaciella igualensis Britton & Rose

Acaciella sotoi L. Rico

Calliandropsis nervosus (Britton & Rose) H.M. Hern. & P. Guinet

Dalea laniceps Barneby

Dalea parrasana Brandegee

Hesperothamnus ehrenbergii (Harms) Harms

Hesperothamnus littoralis (Brandegee) Brandegee

Hesperothamnus purpusii (Harms) Harms

Marina brevis León de la Luz

Marina capensis Barneby

Marina catalinae Barneby

Marina divaricata (Benth.) Barneby

Marina interstes Barneby

Marina oculata (Rydb.) Barneby

Mariosousa acatlensis (Benth.) Seigler & Ebinger

Fagaceae

Quercus clivicola Trel. & C.H. Mull.

Quercus radiata Trel.

Quercus tarahumara Spellenb., J.D. Bacon & Breedlove

Quercus verde C.H. Mull.

Fouquieriaceae

Fouquieria leonilae Miranda (Pr)

Fouquieria purpusii Brandegee (P)

Gentianaceae

Geniostemon atarjanus B.L. Turner

Geniostemon rotundifolius Rzed. & Calderón

Gesneriaceae

Achimenes candida Lindl.

Achimenes hintoniana Ramírez Roa & L.E. Skog

Achimenes nayaritensis L.E. Skog

Achimenes occidentalis C.V. Morton

Achimenes pedunculata Benth.

Smithiantha aurantiaca Wiehler

Iridaceae

Ainea conzattii (R.C. Foster) Ravenna (A)

Iteaceae

Pterostemon bravoanus J. Jiménez Ram. & M. Martínez

Lamiaceae

Salvia canescens C.A. Mey.

Salvia dolichantha E. Peter

Salvia univerticillata Ramamoorthy ex Klitg.

Lauraceae

Mocinnodaphne cinnamomoidea Lorea-Hern.

Liliaceae

Hesperaloe tenuifolia G.D. Starr

Loasaceae

Schismocarpus matudae Steyerm.

Schismocarpus pachypus S.F. Blake

Malphighiaceae

Lasiocarpus multiflorus Nied.

Lasiocarpus ovalifolius Nied.

Malvaceae

Bastardiastrum tarasoides Fryxell

Bastardiastrum tricarpellatum (B.L. & Rob. & Greenm.) D.M. Bates

Periptera lobelioides Fryxell & S.D. Koch

Periptera trichostemon Bullock

Nyctaginaceae

Grajalesia fasciculata (Standl.) Miranda

Grajalesia ferruginea Miranda

Oleaceae

Hesperelaea palmeri A. Gray (P)

Onagraceae

Lopezia clavata Brandegee

Lopezia lopezioides (Hook. & Arn.) Plitmann, P.H. Raven & Breedlove

Lopezia ovata (Plitmann, P.H. Raven & Breedlove) Plitmann, P.H. Raven & Breedlove

Lopezia smithii Rose

Lopezia suffrutescens Munz

Megacorax gracielanus S. González & W.L. Wagner

Orchidaceae

Hagsatera rosilloi R. González

Mexipedium xerophyticum (Soto Arenas, Salazar & Hágsater) V.A. Albert & M.W. Chase (P)

Nezahualcoyotlia gracilis (L.O. Williams) R. González

Physogyne garayana R. González & Szlach.

Physogyne sparsiflora (C. Schweinf.) Garay

Svenkoeltzia luzmariana R. González

Svenkoeltzia pamelae Szlach., Rutk. & Mytnik

Orobanchaceae

Castilleja filiflora G.L. Nesom

Castilleja hidalgensis J.M. Egger

Castilleja macrostigma B.L. Rob.

Castilleja ornata Eastw.

Castilleja perelegans G.L. Nesom

Castilleja sphaerostigma Eastw.

Castilleja stipifolia G.L. Nesom

Castilleja tancitaroana G.L. Nesom

Eremitilla mexicana Yatsk. & J.L. Contr.

Lamourouxia brachyantha Greenm.

Lamourouxia macrantha M. Martens & Galeotti

Lamourouxia nelsonii B.L. Rob. & Greenm.

Phytolaccaceae

Nowickea glabra J. Martínez & J.A. McDonald

Nowickea xolocotzii J. Martínez & J.A. McDonald

Poaceae

Muhlenbergia brevis C.O. Goodd.

Muhlenbergia majalcensis P.M. Peterson

Olmeca clarkiae (Davidse & R.W. Pohl) Ruiz-Sanchez, Sosa & Mejía-Saules

Olmeca zapotecorum Ruiz-Sanchez, E., Sosa & Mejía Saules

Otatea glauca L.G. Clark & G. Cortés

Otatea ramirezii Ruiz-Sanchez

Otatea transvolcanica Ruiz-Sanchez & L.G. Clark

Otatea ximenae Ruiz-Sanchez & L.G. Clark

Rhamnaceae

Karwinskia calderonii Urb.

Karwinskia johnstonii R. Fernandez

Rubiaceae

Carterella alexanderae (A.M. Carter) Terrell

Habroneuron radicans (Wernham) S.P. Darwin

Omiltemia parvifolia Borhidi & K.Velasco

Placocarpa mexicana Hook. f.

Stenotis gracilenta (I.M. Johnst.) Terrell

Stenotis peninsularis (Brandegee) Terrell

Stylosiphonia glabra Brandegee

Rutaceae

Ptelea baldwinii Torr. & A. Gray

Ptelea confinis Greene

Ptelea megacarpa Rose ex Greene

Ptelea obscura Greene

Ptelea obtusata Greene

Ptelea subintegra Greene

Sapindaceae

Balsas guerrerensis Cruz Durán & K. Vega

Scrophulariaceae

Leucophyllum alejandrae G.L. Nesom

Leucophyllum flyrii B.L. Turner

Leucophyllum hintoniorum G.L. Nesom

Leucophyllum langmaniae Flyr

Leucophyllum lanosum Flyr

Leucophyllum mojinense Henrickson & T. Van Devender

Leucophyllum ultramonticola Flyr

Leucophyllum virescens I.M. Johnst.

Solanaceae

Physalis heterophylla Nees

Physalis virginiana Mill.

Physalis walteri Nutt.

Solanum johnstonii Whalen

Solanum morelliforme Bitter & Münch

Solanum tribulosum S. Schauer

Tzeltalia amphitricha (Bitter) E. Estrada & M. Martínez

Tzeltalia calidaria (Standl. & Steyerm.) E. Estrada & M. Martínez

Zygophyllaceae

Morkillia acuminata Rose & Painter

Viscainoa pinnata Gentry