identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
C4B21994A252514786F59A12AFB2D650.text	C4B21994A252514786F59A12AFB2D650.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Dioon nuusaviorum Mart. - Dominguez, Nic. - Mor. & D. W. Stev. 2026	<div><p>Dioon nuusaviorum Mart. - Domínguez, Nic. - Mor. &amp; D. W. Stev. sp. nov.</p><p>Figs 2, 3, 4</p><p>Diagnosis.</p><p>Dioon nuusaviorum sp. nov. differs from D. holmgrenii by having leaflets imbricate to strongly imbricate, each with three to six long marginal teeth (0.26–0.37 cm long), a margin of the leaflets curved acroscopically, microsporophylls with an acuminate apex and megasporophylls with an apiculate apex. In contrast, D. holmgrenii has non-imbricate leaflets (generally a 0.2–1.0 cm between leaflets) with two to five short teeth on the distal margin (0.15–0.29 cm long), a margin of the leaflets straight, microsporophylls with an acute apex and megasporophylls with an acuminate apex. In comparison to D. stevensonii, this new species differs by its light green leaflets at emergence (vs golden), leaflet imbricate to strongly imbricate (vs not imbricate), acuminate apex of microsporophylls (vs acute), tomentose indument and narrowly-triangular megasporophylls at maturity (vs pubescent at base or scarcely pubescent and triangular).</p><p>Type.</p><p>Mexico • Guerrero: Tlacoachistlahuaca, near Rancho Viejo, 1,140 m elev., 28 May 2019, F. Nicolalde-Morejón et al. 3156 (holotype CIB, 22584 UV; isotype MEXU) .</p><p>Description.</p><p>Stem epigeous, erect to decumbent, up to 300 cm in length, up to 32 cm in diameter, covered by persistent leaf bases, sometimes bifurcate in mature plants. Cataphylls persistent, coriaceous, linear to narrowly triangular, yellowish green, densely light brown tomentose abaxially at emergence, densely pubescent at senescence, apex acuminate, 9.0–13.0 × 0.5–1.2 cm at base. Leaves 20–50, dropping at maturity, 100–150 cm long, light green at emergence, tomentum brown at emergence, turned grayish brown later, glabrous at maturity. Petiole subterete, 12–18 cm long, unarmed, green in mature leaves, densely light brown tomentose when young and glabrous at maturity. Rachis subterete, linear, 85–174 cm long, unarmed, green in mature leaves, densely light brown tomentose when young and glabrous at maturity. Leaflets 97–167 pairs, linear-lanceolate, imbricate to strongly imbricate, coriaceous, opposite to subopposite, acroscopically curved margin, plane, green, adaxial and abaxial surfaces glabrous, apex acuminate and non-reflexed, base attenuate, articulations yellowish, inserted at right angles on the rachis, margins deeply denticulate, with up to four serrations on the distal margin, and 1 or 2 on the proximal margin, denticles 0.26–0.37 cm long; median leaflets 6.8–12.3 × 0.65–0.98 cm long. Pollen strobilus solitary, ovoid when emerging, angular cylindrical at maturity, densely light brown tomentulose, 42–44 cm in length, 8.2–8.5 cm in diameter, light brown pubescent at emergence, greyish brown pubescent at maturity; peduncle tomentulose, brown, 5.0– 7.2 cm in length, 2.0–3.0 cm in diameter; microsporophylls 3.4–3.8 × 1.5–2.0 cm, cuneiform, fertile portion covering 2 / 3 of the abaxial surface, sterile portion triangular, reflexed distally ending with a slight pungent apex, 1.23–1.3 cm long; synangia with 4–5 sporangia; 1.3 a 1.5 cm distal end infertile. Ovulate strobilus solitary, ovoid, erect, 45–56 cm in length, 25.46–27.5 cm in diameter, light brown tomentulose at emergence, greyish brown tomentulose at maturity; peduncle tomentose, brown, 6.0– 7.2 cm in length, 3.5–4.2 cm in diameter, basal scales of megasporophylls light green to yellowish green with acute apex; megasporophylls 8.5–12 × 4.8–5.4 cm, strongly imbricate, distal portion triangular with an apiculate and non-reflexed apex, green, tomentose. Seeds ovoid, 2.77–3.35 cm in length, 1.99–2.31 cm in diameter, light brown at maturity, sarcotesta light yellow at maturity, sclerotesta smooth with 13 to 15 radial ridge-like markings extending from micropylar to chalazal end.</p><p>Additional specimens examined</p><p>(paratypes). Mexico • Guerrero: Tlacoachistlahuaca, near Rancho Viejo, 1,190 m, 28 May 2019, F. Nicolalde-Morejón et al. 3152-3155 (CIB, 22580 UV; 22581 UV; 22582 UV; 22583 UV) ; L. Martínez-Domínguez et al. 1745 (CIB, 22079 UV), 1746 (22080 UV, XAL); 1747-1749 (CIB, 22081 UV; 22082 UV; 22083 UV); La Trinidad, 1,030 m, 28 May 2019, F. Nicolalde-Morejón et al. 3157 (CIB, 22585 UV), 3158 (XAL), 3159-3162 (CIB, 22587 UV; 22588 UV; 22589 UV; 22590 UV) ; L. Martínez-Domínguez et al. 1750 (XAL), 1751-1755 (CIB, 22085 UV; 22086 UV; 22087 UV; 22088 UV; 22089 UV) .</p><p>Etymology.</p><p>“Ñ uu savi ”is an endonym translated as“ people of the rain ” (“Ñ uu savi ”has come to substitute“ Mixtec ” as the name of this ethnic group, as the latter is a Spanish adjustment of mixtecatl, the Nahuatl name for “cloud people”).</p><p>Distribution and ecology.</p><p>Dioon nuusaviorum is known only from the Sierra Madre del Sur, in the Guerrero highlands district of Mexico. The habitat is pine and pine-oak forest, with an elevation between 1,030 and 1,190 m, composed of clay soils with scattered karstic rocks. The region has temperate climate with a pronounced rainy season during the summer months.</p><p>Phenological observations.</p><p>Leaf production occurs annually in May. On average, each adult plant produces 12–18 leaves, although some individuals produce only 9–10 leaves. Ovulate strobili were observed in the late ovulate phenophase from May to June, and pollen strobili were recorded in the open pollen phenophase from March to April.</p><p>Preliminary conservation status.</p><p>Three populations of this new species were recorded in the study area (Fig. 1). They thrive in pine-oak and pine forests, which are highly threatened ecosystems due to frequent forest fires (Alfaro-Reyna et al. 2020). Each population has more than 50 adult individuals. Two of the populations are threatened because they occur in areas disturbed fire. In contrast, one population is in a less fire-prone site and appears to be in a better condition for conservation (Fig. 3 C). Population sizes are relatively high, with good recruitment of seedlings and juvenile plants. In addition to fire, a major conservation threat to the species is the expansion of the agricultural frontier. Based on calculations from GeoCAT, the extent of occurrence (EOO) is 11.662 km 2 and the area of occupancy (AOO) is 12.000 km 2. Following the IUCN criteria, the species is preliminarily assessed as Endangered [EN (B 1 ab (ii, v)); C 2 a (i)].</p></div>	https://treatment.plazi.org/id/C4B21994A252514786F59A12AFB2D650	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Martínez-Domínguez, Lilí;Nicolalde-Morejón, Fernando;Stevenson, Dennis Wm.;Lorea-Hernández, Francisco G.;Vergara-Silva, Francisco	Martínez-Domínguez, Lilí, Nicolalde-Morejón, Fernando, Stevenson, Dennis Wm., Lorea-Hernández, Francisco G., Vergara-Silva, Francisco (2026): A striking new species of Dioon (Zamiaceae) from pine and pine-oak forest of Guerrero, Mexico. PhytoKeys 274: 229-245, DOI: 10.3897/phytokeys.274.173907
