Euphorbia breedlovei V.W. Steinm. & P. Carrillo, 2018

Steinmann, Victor W. & Carrillo-Reyes, Pablo, 2018, A revision of the New World Euphorbia adiantoides complex (Euphorbiaceae), Phytotaxa 350 (3), pp. 201-222 : 212-215

Euphorbia breedlovei V.W. Steinm. & P. Carrillo , sp. nov. ( Fig. 5 )

Similar to Euphorbia adiantoides but differs by having smaller leaves and smaller seeds with low, mostly conical, non-translucent tubercles.

Type: — MEXICO. Morelos: municipio de Cuernavaca, around the grounds of the Universidad Autónoma del Estado de Morelos, 18°58’54”N, 99°14’12”W, 1890 m, 16 November 1996, V.W. Steinmann & R. Cerros T. 1160 (holotype MEXU!, isotypes ARIZ!, HUMO!, IBUG!, RSA!).

Annual 15–40 cm tall, from a slender fibrous root. Stems erect or subprostrate, terete, glabrous or rarely sparsely pilose, internodes 1–3.5(–5.5) cm long. Leaves alternate or the lower-most pair opposite; stipules inconspicuous, subulate, 0.1–0.4 mm long, at each side of the base of the petiole; petioles about as long as the blade, slender, 0.6–2.5 cm long, glabrous or rarely sparsely pilose; blade orbicular, ovate or ovate-lanceolate, 0.8–2.2 × 0.6–1.8 cm, base rounded, apex obtuse, rarely obcordate or retuse, often mucronulate with a mucro to 0.1 mm long, margin entire, both surfaces glabrous to sparsely sericeous, penninerved with a prominent midvein, membranaceous. Cyathia in open, mostly weakly defined axillary dichasia 1–4 cm long, rachis papillose, pilose to villose; dichasial bracts opposite; stipules filiform-subulate 0.4–1.3 mm long; blade narrowly ovate, ovate or orbicular, 0.3–0.6 × 0.2–0.3 cm, with a mucronate to caudate tip 0.2–1.4 mm long, pilose to sericeous or rarely glabrous; peduncle 0.3–2.8 mm long, glabrous, papillose. Involucre campanulate to obconical, 0.9 × 0.7–0.9 mm, glabrous or pilose; glands (4–)5, transversely oblong to transversly reniform, 0.1–0.2 × 0.2–0.5 mm; appendages divided into 4–7 filiform segments, 0.4–1.2 × 0.05 mm, glabrous; lobes ovate, 0.2–0.3 mm long, laciniate to fimbriate. Staminate flowers 10–20. Ovary globose to oblate, pilose; styles 3, free to the base, entire, 0.4–0.7 mm long, cylidrical to nearly filiform, glabrous, stigmas capitate. Capsule on a glabrous gynophore exserted by 1.2–2.9 mm, oblate, 3-lobed, 1.5–2.1 × 1.8–2.6 mm, pilose; columella 0.9–1.7 mm long. Seeds ovoid, rounded in cross-section, 0.9–1.2(–1.4) × 0.6–0.9 mm, grey when young to dark-brown or almost black at maturity, apex rounded, base rounded to truncate, with longitudinal rows of isodiametric depressions the bottow having a punctiform pit and bordered by low, conical, non-translucent tubercles; ecarunculate.

Distribution, habitat, and phenology: — Euphorbia breedlovei is known from central-south Mexico, ranging from Guanajuato and Querétaro to Chiapas ( Fig. 4 ). Given its occurrence in the highlands of central and southern Chiapas, it is expected in adjacent Guatemala. It grows in arid scrub, oak forest, pine woodland and pine-oak forest and rarely cloud forest and tropical deciduous forest at elevations from 1380 to 2480 m. It has been reported to be “weedy” at some localities. Flowering and fruiting overlap broadly and occur from June to at least December.

Conservation status: — Euphorbia breedlovei is known from 46 localities in central and southern Mexico. Many of these localities are located in Natural Protected Areas such as the Sierra Gorda Biosphere Reserve, the Corredor Biológico Chichinautzin, and the Tehuacán-Cuicatlán Valley Biosphere Reserve ( CONANP, 2018). Field observations suggest that there are apparently no conservation concerns at present. The Extension of Occurrence (EOO) is 253,563 km 2, and thus E. breedlovei is preliminary assigned to the category of Least Concern (LC) following the IUCN Red List criteria (IUCN 2012).

Common names and uses: — This species has the following common names: “chu’ tz’i’ momol” (C. Santíz 335) in the language Tzotzil and “pojobil wamal” (Brett 500) and “sakil wamal” (E. Santíz 321) in the language Tzeltal. According to label data, there are various reports of this species being used medicinally. The information on C. Santíz 335, states that the latex is applied to wounds; Brett 500 indicates that the latex is used medicinally in the eyes; and E. Santíz 321 reports that mashed leaves are used to prepare a solution that is applied topically for the chills.

Etymology: — This species is named after the late Dennis E. Breedlove (1939–2012), a prolific collector of Mexican plants, authority on the plants of Chiapas, and author of the only checklist of the vascular plants occurring in this state ( Breedlove 1986). He collected the taxon three times in Chiapas during the 1980s.

Morphology and phylogenetic relationships: — Euphorbia breedlovei is similar to E. adiantoides , and it was routinely determined as the synonymous name E. sonorae . Both are annual and the distinctions between them are admittedly subtle and lie primarily in the mature seeds (see couplet 3 of the key). Furthermore, there are differences in leaf size, and the largest leaves of the primary stems in Euphorbia adiantoides are usually more than 2.5 cm long, whereas in Euphorbia breedlovei , they are less than 2.5 cm long. However, whereas there are some plants of E. adiantoides that have relatively smaller leaves and thus appear as those of Euphorbia breedlovei , the leaves of E. breedlovei are not known to enter the larger range of size of E. adiantoides . There are also some differences associated with the stipules of the dichasial bracts. They tend to be longer in E. adiantoides ((0.5–) 1.2–3.2 mm long) and shorter in E. breedlovei (0.4–1.3 mm long).Although Euphorbia breedlovei is characteristically annual, but we have encountered two collections that appear to be from plants persisting for more than one season: Raz & Cerros 135 and Rzedowski 24913.

In the field Euphorbia breedlovei can be easily confused with both Euphorbia subreniformis Watson (1886: 439) and E. ocymoidea , two closely related species that are part of a separate clade within sect. Alectoroctonum ( Yang et al. 2012) . In fact, there are mixed collections of it with the latter species. When examined closely, E. breedlovei is readily distinguished by the well-developed stipules of the dichasial bracts and the entire styles. In both E. subreniformis and E. ocymoidea the stipules are rudimentary and the styles divided.

Additional specimens examined (paratypes): — MEXICO. Chiapas: mpio. Tenejapa, near paraje Krus Chen, [16°49’42”N, 92°28’20”W], 2220 m, 21 December1980, D.E.Breedlove 48852 (MEXU);mpio.Comitán de Domínguez, Laguna Chamula microwave tower between Amatenango del Valle and Comitan, [16°29’28”N, 92°19’07”W], 2440 m, 24 September 1988, D.E. Breedlove 70064 (MEXU, MO); mpio. San Cristóbal de las Casas, NE edge of San Cristóbal de las Casas, [16°44’43”N, 92°36’36”W], 2250 m, 5 November 1981, D.E. Breedlove & G. Davidse 54716 (CAS); mpio. Tenejapa, San Juan Cancuc, [16°51’11”N, 92°29’13”W], 5500 ft, 19 September 1991, J. Brett 500 (MO); mpio. Tenejapa, 300 m SW de Shishintonil, 16º51’11”N, 92º29’13”W, 2030 m, A. Chamé & A. Luna 327 (XAL); mpio. Comitán de Domínguez, 17 km NW of Comitán on Hwy. 190, [16°22’58”N, 92°14’14”W], 1920 m, 4 October 1984, M.J. Huft et al. 2318 (MEXU, MO); mpio. Chamula, San Juán Chamula, [16°47’29”N, 92°41’30”W], 6900 ft, 07 November 1987, C. Santíz 335 (CAS, ENCB, MEXU); mpio. San Juan Cancuc, 4 km de Cancuc, Bakel Te’el, arriba de Cruzjil Ja’, [16°52’24”N, 92°21’20”W], 4200 ft, 16 December 1987, E. Santíz 321 (MO); mpio. La Trinitartia, along Hwy. 190, 58 km N of El Jocote (Empalme), 7 km from La Trinitaria, [16°04’07”N, 92°02’44”W], W.D. Stevens & E. Martínez 25780 (MEXU); mpio. Pueblo Nuevo Solistahuacán, 3 km NW of Pueblo Nuevo Solistahuacán, 17º30’N, 92º40’W [corrected to 17°11’13”N, 92°54’36”W], 5400 ft, 11 October 1971, R.F. Thorne & E. Lathrop 46544 (RSA). Distrito Federal: deleg. Xochimilco, San Gregorio Atlapulco, [19°14’50”N, 99°03’26”W], 2300 m, 10 December 1972, B.F. Páez s.n. (ENCB, MEXU). Guanajuato: mpio. Atarjea, 7 km al N de Carricillo, sobre el camino a La Florida, [21°21’20”N, 99°48’43”W], 2200 m, J. Rzedowski 52940 (IEB). Guerrero: mpio. Tixtla de Guerrero, a 4 km al E de Tixtla, a 25 km al E de Chilpancingo, [17°35’25”N, 99°21’30”W], 7 December 1982, L. Rico et al. 461 (MEXU, MO); mpio. Ixcateopan de Cuahutemoc, Ixcateopan, 4.5 km al N, camino Taxco–Ixcateopan, 18°31’29”N, 99°44’39”W, 2150 m, 23 September 1997, S. Valencia 1641 (MEXU). Mexico: mpio. Temamatla, 3 km al SE de San Pablo Atlazalpan, [19°11’26”N, 98°53’28”W], 2350 m, 25 November 1983, J. Rzedowski 38331 (CAS, ENCB, IEB, MEXU, MO). Morelos: mpio. Tepotzlán, San Juan Tlacotenco, 0.3 km al ESE de la antigua estación de tren El Parque, 19°00’58”N, 99°05’48”W, 2310 m, 16 October 2009, P. Carrillo-Reyes & F. García-Lara 5601b (IBUG); mpio. Tlayacapan, Barranca Tepecapa, 18°57’45.0”N, 99°00’45.9”W, 1857 m, October 2010, R. Hernández-Cárdenas et al. 215 (RSA); mpio. Tlayacapan, Barranca Tepecapa, 18°57’29.7”N, 99°00’44.4”W, 1810 m, October 2010, R. Hernández-Cárdenas et al. 260 (RSA); mpio. Huitzilac, Huitzilac, [19°01’N, 99°16’W], 16 October 1937, E. Lyonnet 1770 (MEXU); mpio. Jiutepec, cerca Lago Ahuayapan, Tejalpa, [18°53’N, 99°09’W], 1400 m, 12 December 1979, R. Medina 130 (MEXU); mpio. Yautepec, Cañón de Lobos, [18°52’14”N, 99°07’10”W], 26 Oct 1941, F. Miranda 1637 (MEXU); mpio. Tepoztlán, Tepoxteco, [19°00’02”N, 99°06’04”W], 30 March 1941, F. Miranda 1235 (MEXU); mpio. Cuernavaca, Cuernavaca, [18°58’N, 99°13’W], 5000 ft, 14 February 1899, C.G. Pringle 8000 (MEXU, MO, MICH, P, POM, UC); mpio. Tepoztlán, Parque de Tepoztlán, [18°59’07”N, 99°05’57”W], 3 October 1943, D. Ramírez C. 209 (MEXU); mpio. Tepoztlán, Sierra de Tepoztlán, approx. 6 km NW of Tepoztlán, via road, just W of the intersection with train tracks, near 19º00’N, 99º10’W, 1700 m, 2 August 1997, L. Raz & R. Cerros T. 135 (RSA). Oaxaca: mpio. San Juan Bautista Suchitepec, 1.6 km E of Hwy. 125 on the rd to Guadalupe Cuautepec at km 85 from Tehuacan on Hwy. 125, [18°01’44”N, 97°40’54”W], 1960 m, B. Bartholomew 3082 (CAS); mpio. Santo Tomás Tamazulapam, km 112 carretera Oaxaca –Pto. Ángel, aprox. 9.5 km en línea recta al SE de Miahuatlán de Porfirio Díaz, 16°15’N, 96°33’W, 2020 m, 04 November 2005, P. Carrillo-Reyes et al. 4949 (IBUG); mpio. Sola de Vega, Ranchería de San Antonio, 3.3 km al NO de San Sebastián de la Grutas, 16º 38’57”N, 96º 58’58”W, 1960 m, 7 November 2005, P. Carrillo-Reyes et al. 4984 (IBUG); Dto. Huajuapan, mpio. Huajolotitlán, 4 mi N of Huajuapan, [17°50’59”N, 97°43’28”W], 5500 ft, 27 Sep 1957, R.L. Dressler 2270 (MO); Dto. Huajuapan, mpio. San Pedro y San Pablo Tequixtepec, cañada del río Huichiquila, 18º07’27.47”N, 97º35’00.61”W, 1911 m, 7 December 2009, N. González Casteñeda 149 (IBUG); Dto. Coixtlahuaca, mpio. Villa Tepelmeme de Morelos, km 99 carr. Coacnopalan– Oaxaca, 18º06’N, 97º20’W, 1680 m, 17 September 1994, A. Salinas T. & E Martinez-Correa 7923 (RSA); Dto. Huajuapan de León, mpio. Zapoquila, entre Río Grande y Membrillos, 18º02’N, 97º 33’W, 2200 m, 10 September 2001, P. Tenorio L. et al. 20884 (RSA). Puebla: mpio. Caltepec, Rincón del Guayabo. 5.1 km al SSO de San Luis Atolotitlán, 18º09’39”N, 97º24’54”W, 2080 m, matorral xerófilo, 22 Nov 2005, P. Carrillo-Reyes & D. Cabrera-Toledo 5059 (IBUG); mpio. Caltepec, Barranca Rincón del Guayabo (tributaria de Barranca de Coyomeapa), 5 km al S de San Luis Atolotitlán, 18º08’33”N, 97º24’55”W, 1980–2050 m, 06 November 2011, P. Carrillo-Reyes & D. Cabrera-Toledo 6506 (IBUG); mpio. Caltepec, San Luis Tultitlanapa, 2 km al SE de San Luis Atolotitlán, rumbo a Caltepec, [18°11’00”N, 97°26’22”W], 2000 m, 20 July 1983, F. Chiang et al. 2423 (F, RSA); mpio. Atlixco, SO de San Pedro Benito Juárez, 18º56’30”N, 98º34’W, 2250 m, 25 November 1986, O. Dorado et al. 396 (IEB); mpio. Caltepec, vic. of San Luis Tultitlanapa, [18°11’N, 97°25’W], July 1908, C.A. Purpus 3422 (F, UC); Rancho Posada, [19°04’N, 98°13’W], 2184 m, October 1909, J. Nicolas 370 (P); mpio. de San Andrés Cholula, ladera E del Cerro Tacajete, cerca de San Miguel Papaxtla, [19°03’N, 98°23’W], J. Rzedowski 24913 (ENCB, F); mpio. Caltepec, La Compañia, 4 km al NO de Caltapec, [18°12’19”N, 97°30’48”W], 22 August 1987, A. Salinas T. 4485 (DAV); mpio. Caltepec, La Mesa de Buenavista, al N de Caltepec, [18°12’45”N, 97°27’27”W], 2100 m, 19 September 1984, P. Tenorio & C. Romero de Tenorio 7253C (MO); mpio Caltepec, Rincón de la Hierba, la Mesa Chica al W de Caltepec, [18°12’09”N, 97°27’203”W], 2120 m, 8 October 1984, P. Tenorio L. & C. Romero de Tenorio 7609 (ENCB, MO); mpio. San Andrés Cholula, camino por el lado S de Santiago Xalitzintla, 19º04’45”– 19º03’40”N, 98º31’– 98º30’30”W, 2580– 2560 m, M. Tlapa & G.Ubierna 126 (XAL); mpio. San Andrés Cholula, Cañada Grande, por el lado NO de San Pedro Yancuictlalpan, 19°04’30”– 19°06’N, 98°29’– 98°30’15”W, M. Tlapa & G. Ubierna 179 (MEXU); mpio. San Nicolás de los Ranchos, camino a Cuahuitenco, lado N San Pedro Yancuictlalpan, 19º04’50”N, 98º28’50”W, 2480 m, 8 August 1988, M. Tlapa & G. Ubierna 2091 (IEB, XAL); mpio. Tzicatlacoyan, camino que va desde el dique de la presa de Valsequilla hacia el S, aprox. 3 km al S del dique, cerca de la desviación hacia Balbanera, a la derecha el Cerro El Jaguey, 18º53’N, 98º06’W, 2160 m, H. Vibrans 2887 (MEXU); mpio. San Andrés Cholula, camino de Cholula a San Buenaventura Nealtican, 2.7 km después de la desviación a Santa María Acuesocomac, 19º03’N, 98º24’W, 2200 m, 16 September 1990, H. Vibrans 3151 (IEB, MEXU). Querétaro: mpio. Peñamiller, 0.5 km al S de Río Blanco, 21º12’04”N, 99º42’24”W, 1900 m, 28 August 2005, P. Carrillo-Reyes & V. Sosa 4691 (IEB); mpio. Peñamiller, 4 km al S de Río Blanco, [21°11’N, 99°45’W], 11 November 1988, J. Rzedowski 47674 (IEB).

Euphorbia multiseta Bentham (1840: 51) . Eumecanthus multisetus (Bentham) Millspaugh (1916: 414) . Type: — MEXICO. Michoacán: Morelia, 1839, T. Hartweg 388 (holotype K-000253719!; isotypes K-000253720!, MO-3576922!, NY!, P-00607264!). The holotype at K gives the year of collection as 1839, whereas the isotype at NY states it was collected in 1840. Both bear the same collection number. We are uncertain if these specimens represent two separate collection events or simply an error when transcribing the year to the label.

Perennial herb (0.4–)0.6–1.5(–2.2) m tall, from a thickened and often woody taproot. Stems erect or arching, usually unbranched or little branched from the base, slightly angled or rarely winged, glabrous or sparsely pilose towards the tips, internodes 1–8 cm long. Leaves alternate; stipules inconspicuous, subulate to filiform, 0.3–0.5 mm long, often purple, at each side of the base of the petiole; petiole slender 1–4 cm long, glabrous or sparsely pilose; blade ovate, lanceolate or oblong, 1–4.2(–5) × 0.25–2(–2.6) cm, becoming noticeable narrower towards the tips of the branches, base cuneate to attenuate, apex acute to acuminate to the apex, often with a mucro to 1 mm long, margin entire, often with dark purplish-red slightly revolute margins, glabrous or rarely with scattered spreading hairs, penninerved with a prominent midvein, membranaceous to subcoriaceous. Cyathia in congested axillary dichasia 2–8 cm long, often concentrated towards the ends of the branches and collectively giving the appearance of a terminal inflorescence, rachis papillose, sparsely pilose to glabrate; dichasial bracts opposite; stipules subulate-filiform, (0.6–) 1.2–2.4 mm long; blade narrowly ovate, lanceolate, narrowly elliptic to almost linear or even filiform, rarely ovate or orbicular, 0.4–1.3 × 0.5– 0.3 cm, usually more than 2x longer than wide, with a cuspidate to caudate tip 0.7–2.7 mm long, glabrous to strigulose; peduncle 0.7–1.8 mm long, glabrous. Involucre campanulate, 0.7–0.8 × 0.8–1.0 mm, pilose; glands 5, transversely oblong to transversely reniform, 0.1–0.15 × 0.3–0.4 mm; appendages glabrous, divided into 5–7(–10) filiform segments, 0.3–0.6 × 0.05 mm, glabrous; lobes oblong, 0.1–0.2 mm long, fimbriate to laciniate. Staminate flowers 10–15. Ovary globose, 3-lobed, pilose; styles 3, free to the base, entire, 0.3–0.4 mm long, cylidrical, glabrous, stigmas capitate. Capsule on a gynophore exserted by 2.2–4.6 mm, glabrous, oblate, 3-lobed, 2.2–2.9 × 3.2– 3.7 mm, glabrous to pilose; columella 1.8–2.5 mm. Seeds ovoid, rounded in cross-section, 1.5–1.9 × 1.2–1.5 mm wide, dark-brown to blackish, apex rounded, base rounded to truncate, with longitudinal rows of isodiametric depressions the bottow having a punctiform pit and usually bordered by low, conical, non-translucent tubercles, rarely the tubercles conspicuously elevated and translucent; ecarunculate.

Distribution, habitat, and phenology: — Euphorbia multiseta is endemic to western Mexico, ranging from southern Sinaloa to Guerrero ( Fig. 4 ). It occurs in mountainous regions of the Sierra Madre Occidental, Sierra Madre del Sur, and western portion of the Trans-Mexican Volcanic Belt, where it is frequent in humid pine-oak forest, oak woodland, cloud forest, and rarely tropical subdeciduous forest. One collection is from the ecotone of oak forest and tropical deciduous forest. It has been collected at elevations of 800 to 2500 m, but mostly in areas above 1600 m. Flowering has been recorded from June to November, with mature fruits from August to November.

Conservation status: — Euphorbia multiseta is known from 60 localities in northern and central Mexico. Some of these localities are located in Natural Protected Areas such as the Sierra de Manantlán Biosphere Reserve and the Insurgente José María Morelos National Park ( CONANP 2018). Field observations suggest that there are apparently no conservation concerns at present. The Extension of Occurrence (EOO) is 135,201 km 2, and thus E. breedlovei is preliminary assigned to the category of Least Concern (LC) following the IUCN (2001, 2014) Red List criteria.

Common name: — In Sinaloa, it has the common name “finillo” (González Ortega 7116). It apparently has no conservation concerns at present.

Morphology and phylogenetic relationships: — Euphorbia multiseta is closely related to E. adiantoides ; see the latter for a discussion of their similarities and differences. It shares with E. zamudioi a perennial habit, and these to can be distinguished by the features given in couplet 2 of the key. An illustration of Euphorbia multiseta was published by Boissier (1866: pl. 36).

Additional specimens examined: — MEXICO. Jalisco: mpio. Autlán de Navarro, rd from El Chante to El Guisar in the Sierra de Manantlán, [19°34’32”N, 104°11’56”W], 2160 m, 17 August 1980, D.E. Breedlove 45738 (CAS); mpio. Talpa de Allende, near Puerto El Triunfo 19 km WSW of Talpa de Allende along road to La Cuesta and Tomatlan, [20°13’N, 104°46’W], 1555 m, 11 September 1986, D.E. Breedlove & B. Anderson 64106 (MEXU); mpio. Talpa de Allende, Arroyo del Mosco, 2.3 km al SE de Las Mesas por el camino a Cuale (1 km en línea recta), 20º29’55.3”N, 105º06’16.9”W, 1080–1100 m, 10 November 2009, P. Carrillo-Reyes & C. Gallardo 5812 (IBUG); mpio. Puerto Vallarta, 0.3 km al SE de El Nogal por el camino a Cuale, 20º32’37”N, 105º 05’49”, 880–900 m, 11 November 2009, P. Carrillo-Reyes et al. 5833 (IBUG); mpio. Villa Purificación, Villas de Cacoma , 19°49’23.5”N, 104°33’26.8”W, 1069 m, 08 January 2013, R. Cuevas et al. 10915 (IBUG); Tamazula de Gordiano, Agua Fría km 35 brecha a Manuel M. Diéguez, [19°33’15”N, 103°08’45”W], 2200 m, 20 November 1972, C.L. Díaz Luna 3637 (GUADA, MICH); mpio. Tamazula de Gordiano, Agua Hedionda, km 60 brecha a Manuel M. Diéguez, Tamazula, [19°45’N, 103°17’W], 1850 m, 27 October 1973, C. Díaz Luna 4531 (ENCB, GUADA, IBUG, MICH); mpio. Tamazula de Gordiano, brecha a Manuel M. Dieguez, km 140, 1800 m, 19 November 1973, L.M. V. de Puga 13883 (IBUG); mpio. Tamazula de Gordiano, brecha de Tamazula a San Juan de La Montaña, 10.8 km directo al E de Tamazula, [19°41’12”N, 103°05’41”W], 1620 m, 15 July 1988, M. Fuentes O. 410 (MICH); mpio. Talpa de Allende, entre Cuale y Los Lobos, [20°25’N, 105°04’W], 1230 m, 7 October 1971, R. González T. 486 (MICH); mpio. Tecalitlán, Puente San José sobre el Río Las Juntas, a ca. 8 km S de Tecalitlán, carretera a Pihuamo, [19°26’02”N, 103°21’19”W], 22 November 1981, E.J. Lott & J.A. Solís M. 816 (F, MEXU); mpio. Tecalitlán. Sierra del Halo, near a lumber rd leaving the Colima highway 7 mi SSW of Tecalitlán and extending SE toward San Isidro, [19°23’57”N, 103°19’58”W], 1530 m, 5 August 1957, R. McVaugh 15999 (MEXU, MICH); mpio. Tecalitlán, in the barranca at Puente San Pedro, 5 mi SW of Tecalitlán, [19°26’17”N, 103°21’00”W], ca. 1200 m, 22 September 1958, R. McVaugh 18101 (MEXU, MICH, NY); mpio. Talpa de Allende, precipitous mountainside 5–8 miles above (N of) La Cuesta, below the pass to Talpa de Allende, [20°12’N, 104°46’W], 1200–1500 m, 16 October 1960, R. McVaugh 20293 (MICH); mpio. Talpa de Allende, mountainside 2.5–4 mi above (N of) La Cuesta, rd to Talpa de Allende, [20°11’N, 104°47’W], 800–1000 m, 20–21 November 1960, R. McVaugh 21186 (MICH); mpio. Tecalitlán, E foothills of the Sierra del Halo, ca. 25 km W of Jilotlán de los Dolores and 56 km from the rd junction 11–12 km SW of Tecalitlán, [19°22’14”N, 103°08’46”W], 1600 m, 20–21 November 1970, R. McVaugh 24553 (MICH); mpio. Autlán de Navarro, mountains 12–15 mi SSE of Autlán, on rd to Corralitos, 4–10 mi above (SE of) Ahuacapán, [19°38’N, 104°20’W], 1500–2200 m, 22–23 November 1959, R. McVaugh & W.N. Koelz 912 (MEXU, MICH); mpio. Cuautitlán de García Barragán, Sierra de Cuautitlán, Las Joyas , [19°35’N, 104°16’W], 1800 m, 20 August 1982, J.A. Pérez de la Rosa 193 (IBUG); mpio. San Sebastián del Oeste, camino antiguo a los Reyes, saliendo de San Sebastián del Oeste, [20°46’45”N, 104°50’12”W], 1564 m, 13–14 August 2009, R. Ramírez-Delgadillo 7684 (IBUG); mpio. Tuxpan, km 9 camino de ascenso al nevado de Colima, por El Fresnito, [19°37’17”N, 103°33’21”W], 2140 m, 07 September 1988, A. Rodríguez et al. 1506 (MEXU); mpio. Tamazula de Gordiano, cerca de Agua Hedionda, ± 45 km al E de El Aserradero, sobre el camino a Manuel M. Diéguez, [19°45’41”N, 103°17’32”W], 1900 m, 26–27 October 1973, J. Rzedowski & R. McVaugh 1163 (ENCB, MEXU, MICH, MO); mpio. Tecalitlán, 3 km al E de Llanitos, brecha a Canutillo, [19°24’10”N, 103°20’09”W], 25 June 1990, J. Villa C. & S.D. Koch 774 (IBUG, IEB, MICH). Guerrero: mpio. José Azueta, distr. Montes de Oca, Vallecitos, [17°55’18”N, 101°19’24”W], 8 October 1937, G.B. Hinton et al. 11484 (F, IJ, MICH, MO, RSA, UC), December 1937, G.B. Hinton et al. 11636 (MICH, RSA, UC); mpio. Zirandaro, en La Saiba Amarilla a 7 km al E de Guayameo, camino Guayameo– Los Placeres del Oro, [18°18’04”N, 101°12’44”W], 14 July 1982, E. Martínez S. & J.C. Soto Núñez 1390 (MEXU, MO); mpio. San Miguel Totolapan, ca. 2 km al S de Las Tunas sobre el camino a San Nicolás del Oro; 17°56’35”N, 100°14’47”W, 1550 m, 5 February 2005, V.W. Steinmann & J.M. Porter 4907 (IEB). Michoacán: mpio. Uruapan, rd to CFE storage reservoir, Rte 37, 18 km S of Uruapan, 6 September 1970, [19°17’00”N, 102°04’27”W], D. Burch 2730 (DAV, MEXU, MO, RSA); distr. Coalcomán, Barroloso, 1850 m, 26 October 1939, G.B. Hinton et al. 15385 (F, IJ, MICH, MO, RSA); mpio. Charo, 10 mi E of Morelia, [19°39’23”N, 100°59’09”W], ca. 7000 ft, 13 July 1940, C.L. Hitchcock & L.R. Stanford 7147 (DS, POM, UC); mpio. Charo, S-facing slopes of mountains between the Río del Salto and La Polvilla, ca. 18 mi E of Morelia, [19°39’05”N, 100°56’52”W], 7200–8000 ft, 9–18 November 1961, R.M. King & T.R. Soderstrom 5006 (MICH, MEXU, UC); mpio. Tzitzio [Queréndaro], a 3 km al S de Mil Cumbres camino a Villa Longin , [19°36’22”N, 100°46’12”W], 2500 m, 11 October 1983, E. Martínez et al. 4806 (ENCB, MO); mpio. Indaparapeo, 24 mi E of Morelia on Highway 15, [19°40’58”N, 100°54’01”W], 25 July 1975, D. Seigler & G. Holstein DS-9648 (MEXU); mpio. Coalcomán de Vázquez Pallares, a 14 km al SW de Coalcomán, carretera a Coahuayana, [18°44’10”N, 103°14’08”W], 1220 m, 25 August 1980, J.C. Soto Núñez & L. Cortés A. 2510 (ENCB, MEXU, MO); mpio. Aguililla, 17.6 km (by road) WSW of La Paz along the rd to Dos Aguas, 18°46’00”N, 102°50’45”W, 1450 m, 11 September 2004, V.W. Steinmann et al. 4688 (IEB); mpio. Charo, El Álamo, 6 km al E de Temazcal, carretera Morelia–Mil Cumbres–Ciudad Hidalgo, [19°40’00”N, 100°55’22”W], 2450 m, 13 October 1983, J.C. Soto Núñez & E. Martínez S. 5503 (CAS, ENCB, F, IBUG, MEXU, MO, XAL); mpio. Coalcomán de Vázquez Pallares, 16 km al E de la carretera Coalcomán–Tepalcatepec, sobre el camino a Dos Aguas, 18°49’19”N, 103°03’48”W, 2100 m, 3 November 2007, V.W. Steinmann & Y. Ramírez-Amezcua 6018 (IEB); mpio. Uruapan, cara S del Cerro de la Cruz, 19°26’20”N, 102°02’15”W, 1800 m, 28 October 2006, V.W. Steinmann et al. 5492 (IEB); mpio. Gabriel Zamora, Cerro Los Tanques, 3 km al N de Charapendo, [19°16’55”N, 102°03’58”W], 1300 m, 30 July 1990, S. Zamudio & V. Sosa 8018 (IEB). Nayarit: mpio. Xalisco, brecha a 2 km al N del Carrizal, entronque de Emiliano Zapata a Cofradia de Chocolac, 21º23’N, 104º56’W, 1115 m, 10 November 1993, J.I. Calzada et al. 18908 (MEXU, MO, XAL); mpio. Tepic, about 11 km W of Tepic, [21°31’N, 105°00’W], R.L. Dressler 2171 (MO); mpio. Amatlán de Cañas, mountains 10 mi SE of Ahuacatlán, on rd to Barranca del Oro, [20°57’47”N, 104°27’55”W], 1100–1300 m, 11–12 August 1959, C. Feddema 283 (MICH), C. Feddema 336 (MEXU, MICH); mpio. Santa María del Oro, slopes and barrancas leading down to the lake NE of Santa María del Oro, [21°22’31”N, 104°33’29”W], 1000 m, 18–20 August 1959, C. Feddema 729 (MEXU, MICH); mpio. Tepic, 5 km al NE del Cuarenteño, camino El Cuarenteño–Izote, 21°55’N, 105°00’W, 1600 m, 15 Sep 1990, G. Flores F. & R. Ramírez R. 2339 (IEB, MEXU, MICH, MO); mpio. Tepic, 1 km al S del km 11 de la carr. Tepic–Miramar o 2 km al SW de Venustiano Carranza, 21º30’47”N, 105º00’08”W, 1150 m, 15 September 1994, G. Flores-Franco et al. 3792 (MEXU, MO, XAL); mpio. Tepic, 14 km del entronque del Izote-Camino al Cuarenteño (Cerro San Juan), 21º27’N, 105º00’W, 1410 m, 24 August 1993, G. Flores-Franco et al. 2876 (MEXU, MICH); mpio. Del Nayar, 14.4 km al SW de Santa Teresa, camino a La Mesa del Nayar, 22°25’N, 104°45’W, 2240 m, 26 September 1989, G. Flores F. & R. Tenorio L. 1408 (MEXU); mpio. Tepic, 1.1 km por la brecha que sale de la carretera Tepic–Jalcocotán rumbo al Cuarenteño, 21º30’55.8”N, 104º58’13.5W, 1144 m, 2 January 2010, J. González 489 (IBUG); mpio. Del Nayar, La Cumbre, 20 km al W después de la Mesa del Nayar, por la carretera Huejuquilla– Tepic, 22º23.59’26.5”N, 104º45’05.61”W, 1687 m, 04 September 2012, J. González-Gallegos et al. 1286 (IBUG); mpio. Xalisco, hills 10 mi SE of Tepic, 2 mi SE of El Refugio, [21°24’04”N, 104°44’46”W], ca. 1100 m, 6 October 1952, R. McVaugh 13379 (MEXU, MICH); mpio. Xalisco, hills near km. 886, ca. 10 mi SE of Tepic, 2 mi SE of El Refugio, [21°24’04”N, 104°44’46”W], 1020–1100 m, 30 August 1957, R. McVaugh 16595 (IEB, MEXU); mpio. Tepic, mountainsides ca. 12 mi W of Tepic, 6.5 mi E of Jalcocotán, [21°30’52”N, 105°03’21”W], 800–1200 m, 7 September 1960, R. McVaugh 18795 (IEB, MEXU, MICH); mpio. Compostela, mountains 9 mi N of Compostela, [21°18’N, 104°52’W], 1000–1200 m, 13 November 1959, R. McVaugh & W.N. Koelz 552 (IEB, MEXU, MICH); mpio. Tepic, along rd from Hwy. 15 (W of Tepic) toward Santa Cruz (Playa Miramar), about 6.3 mi W of Hwy. 15, [21°31’15”N, 104°58’49”W], 7 September 1973, W.D. Stevens & M. Fairhurst 2013 (ENCB, MICH, MO); trail from Tepic to Santiago, 1000 m, 15 September 1926, Y. Mexia 638 (F, MO); mpio. Tepic, rd to Jalcocotán, ca. 8 mi W of Hwy. 15, [21°31’09”N, 104°59’48”W], 20 July 1970, D.H. Norris & D.J. Taranto 13263 (MICH); mpio. Del Nayar, along the rd from Ruiz to Mesa del Nayar, 17 km (by road) ENE of El Maguey, [22°09’46”N, 104°44’55”W], ca. 1650 m, 14 October 1996, V.W. Steinmann & L. Varela E. 1066 (IEB); mpio. Compostela, km 3–4 del camino de terracería que sale en el km 6 sobre la carretera de Compostela a Las Varas, 21º11’N, 104º55’W, 11 September 1985, O. Téllez V. 9213 (IBUG, IEB, MEXU); mpio. San Blas, km 3–4 del camino a Pintadeño, que sale en el km 16 de la carretera Tepic–Miramar, 21º32’N, 105º05’W, 12 September 1985, O. Téllez 9280 (IBUG, IEB, MEXU); mpio. Tepic, km 10 terracería a El Cuarenteño que que empieza a 300–400 m del Izlote, carretera Tepic–Miramar, 21º30’N, 104º55’W, 16 October 1985, O. Téllez V. & F. Chiang S. 9759 (IBUG, IEB, MEXU); mpio. Tepic, 3 km al SE de El Refugio, camino a Guadalajara, 21º25’N, 104º47’W, 6 September 1985, O. Téllez V. & P. Dávila 9009 (IBUG, IEB, MEXU); mpio. Del Nayar, 12 km al NW de Lindavista, camino a Santa Teresa, 22°27’N, 104°54’W, 2200 m, 26 September 1989, P. Tenorio L. & G. Flores F. 16462 (MEXU, MO); mpio. Compostela, road between Compostela and Las Varas, 28 mi by rd SW of Tepic, ca. 21º10’N, 105º00’W, 2900 ft, 19 October 1970, G.L. Webster & G.J. Breckon 15766 (DAV, MEXU, MICH). Sinaloa: mpio. Rosario, Cacolotán, Pichachos, [23°11’22”N, 105°42’20”W], October 1902, J. González Ortega 7116 (CAS, MEXU); mpio. Rosario, along the dirt rd from Rosario to Plomosa, about 2.2 mi E of La Rastra and 2 mi up the grade from a river crossing, about 32 mi E of Mexico Highway 15 at Chilillos, this about 1 mi S of Rosario, [23°04’27”N, 105°29’55”W], 8 October 1975, J.L. Reveal & R.M. Harley 4070 (MICH, MO, NY).

Figures

FIGURE 4. Geographic distribution of species of the Euphorbia adiantoides complex.

FIGURE 5. Euphorbia breedlovei. a. Primary stem with lateral shoots; b. flowering branchlet; c. close-up of a cyathium; d. seeds. Photos by D. Denham.