Zamia sandovalii C. Nelson 2007
Creators: name: Haynes, Jody L.
name: Schutzman, Bart
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Cycadales
Zamiaceae
Zamia
Zamia sandovalii

description: Zamia sandovalii C.Nelson, Ceiba 46(1): 41–42, figs. 1–10. (2007)
Type: — HONDURAS. Atlántida: Tropical humid forest, 200 m, 24 January 2006, G. Sandoval’ et al. 1154 (TEFH!, five sheets).
Description: — Habit cremnophyte (typical) (Fig. 1A, 1B). Stem obovoid to napiform (Fig. 1C, 1D), 15–25 cm long, 12–15 cm diam., acaulescent to decumbent, may be completely subterranean, solitary, lacking persistent leaf bases (Fig. 1C, 1D); taproot to 1+ m long, 4–7 cm diam. At base, distally attenuate (Fig. 1C); coralloid roots in large, amorphous masses often extending above soil surface (Fig. 1E); apex covered in cataphylls (Fig. 1F), remainder of stem bearing closely-spaced circumferential striations resembling growth rings (Fig. 1D); cataphylls elongate triangular to long-acuminate, stipulate, rugulose to rugose, papyraceous, 6–7 cm long, 5–6.5 cm wide at base, medium to dark brown, base appressed, tip acuminate and erect to slightly reflexed (Fig. 1F). Leaves 1–3 per crown (in habitat), 1.5–2.2 m long, 50–75 cm wide, pendulous (when growing on a steep gradient [typical]) (Fig. 2A) to arcuate (when growing on level ground [atypical]) (Figs. 2B, 2C); vernation straight with rudimentary leaflets incubously shielded (when viewed adaxially) (Fig. 2D); leaf base 2.5–5 cm thick, distinctly swollen, bulbous, glabrous, medium green, often with a brown to reddish-brown collar (similar to that of Encephalartos lehmannii Lehm. [1834: 14]) (Fig. 1D); petiole 42–101 cm long, 0.8–2 cm diam., terete to slightly flattened adaxially, lightly armed with small prickles (Fig. 1C, 1D, 1E; 2D); emerging silvery pubescent (Fig. 2C), quickly becoming glabrous; mean petiole:rachis ratio 1:10; rachis 33–105 cm long, terete, unarmed, extending beyond the leaflets into a protracted tip to 1 cm long; bearing 14–35 evenly-spaced leaflet pairs; emerging silvery pubescent (occasionally golden apically), quickly becoming glabrous (Fig. 3D); leaflets lanceolate, falcate (Fig. 2A), 25–38 cm long, 2–4 cm wide (median), mean length:width ratio 8:13; coriaceous, medium green, apex acute to acuminate (Fig. 2A); margins slightly revolute, finely serrulate in distal half to two-thirds; insertion opposite to subopposite, apically oblique, mean pinna-rachis angle (Grobbelaar, 2002) 40º, articulation attenuate, green (Fig. 2E); basally keeled and non-overlapping to succubously imbricate, medially and apically flat to declinate, non-overlapping to succubously imbricate; emerging finely silvery to golden pubescent, quickly becoming glabrous (Fig. 2D); eophyll typically with two pairs of falcate leaflets 6–7 cm long, 1.5–2 cm wide maturity (Fig. 2F). Microsporangiate strobilus cylindrical to long conical, 17.5–31 cm long, 3.3–4.2 cm diam., occurring singly or in groups of 4 or more, medium brown, tan to reddish-brown pubescent (Fig. 3A); apex acute to acuminate, occasionally bearing an apiculum measuring 4–7 mm high (Fig. 3A); erect to leaning at maturity (Fig. 3A); peduncle 6–6.3 cm long, 1.5–1.6 cm diam., medium brown, tan to reddish-brown pubescent, straight to sigmoid (Fig. 3A); microsporophylls 12–13 mm long, 6–7 mm wide, 4–5 mm high, spirally arranged in 18–22 columns and 25–35 rows, oriented perpendicular to cone axis when immature, ascending at dehiscence (Fig. 3A); unexposed adaxial surface concave, tan to olive green, uniformly dotted with lighter colored spots (Fig. 3B); unexposed abaxial surface convex with elevated longitudinal ridge measuring 2–3 mm wide and extending along entire length, tan to olive green, uniformly dotted with lighter colored spots (Fig. 4C); bullae protruding 1–2 mm, trapezoidal in profile, oblong hexagonal in outline, central facet well-defined, oblong hexagonal, concave (Fig. 3A); microsporangia 1–1.5 mm in diam., 14–20 per sporophyll, restricted to unexposed abaxial surface, sparsely distributed in clusters of 2–3 along either side of raised longitudinal ridge, bivalvate at dehiscence, internally striated (Fig. 3C). Megasporangiate strobilus cylindrical, 12–18 cm long, 4.5–9 cm diam., often partially obscured by surrounding cataphylls, causing cone to appear sessile (Fig. 3D, 3E); typically solitary (although a younger cone may occasionally emerge while an older cone is nearing maturity) (Fig. 3D, 3E); dull tan to medium green, tan to reddish-brown pubescent (Figs. 1D; 3D, 3E); apex blunt to acuminate, occasionally bearing an apiculum to 1.9–2.5 cm high (Fig. 3D, 3E); erect to leaning at maturity (Figs. 1C,D; 3D, 3E); peduncle 2.5–5 cm long, 1.5–2.5 cm diam., tan to reddish-brown pubescent (Fig. 1C, 1D); megasporophylls 2.5–3.2 cm long, 2–4 cm wide, 1.8–2.5 cm tall, spirally arranged in 7–12 columns and 8–9 rows, oriented perpendicular to cone axis (Fig. 3D, 3E); bullae protruding 0.5 cm, compressed trapezoidal in profile, oblong hexagonal in outline, central facet often weakly defined, oblong hexagonal to irregular hexagonal, flat to concave (Fig. 3D, 3E); seeds ovoid to 3-sided, 2–2.5 cm long, 1.3–1.7 cm diam., 100–200 per cone, tan, smooth (Fig. 3F); immature sarcotesta white, maturing to reddish-orange (Fig. 3F).
Paratypes: — HONDURAS. Atlántida: 15 August 1962, M. Kimnach 431 (CAVA!); 28 July 2003, J. Haynes et al. JLH03-037, JLH03-038 (TEFH!); 24 January 2006, G. Sandoval et al. (TEFH!).
Distribution: — Zamia sandovalii is endemic to a single river basin on the Caribbean versant of the Cordillera Nombre de Dios, Department of Atlántida, Honduras, within the general area referred to locally as the ‘North Coast’. Plants exhibit an aggregated distribution, typically growing on cliffs, steep hillsides, and road cuts at 100–400 masl, and seeming to prefer slopes of 60–70º (Haynes & Bonta 2003, Sandoval 2006; Figs. 1A, 1B).
Habitat: —Typical habitat is wet tropical forest dominated by large trees, including Bursera simaruba (gumbo limbo) and Ceiba pentandra (kapok), and palms such as Attalea sp. (American oil palm). Other associated species include smaller palms (e.g., Astrocaryum mexicanum, Bactris sp., Chamaedorea costaricana), woody shrubs (e.g., Piper sp., Zanthoxylum foliolosum), aroids (e.g., Monstera sp., Philodendron spp., Syngonium spp., Xiphidium caeruleum), gingers (e.g., Costus spp.), cacti (e.g., Disocactus ramulosus, Epiphyllum oxypetalum, E. phyllanthus var. hookeri, Hylocereus minutiflorus, Rhipsalis baccifera), and ferns (e.g., Lygodium sp., Niphidium crassifolia, Polypodium rhodopleuron) (Haynes & Bonta 2003, Sandoval 2006, Kimnach 2008).
Geology and soils: —The soils of the North Coast region of Honduras are typically weathered from intrusive granite (Kozuch 1991). Samples collected in 2003 from the type locality revealed the following details about its composition: pH = 7.2 (neutral); % organic matter = 7.5 (above average); % total nitrogen = 0.37 (average); available nutrients = 22.1 ppm phosphorus (above average), 104 ppm potassium (average), 2,370 ppm calcium (above average), and 440 ppm magnesium (above average) (Haynes & Bonta 2003).
Climate: — The North Coast of Honduras experiences a tropical climate, with relatively consistent rainfall throughout most of the year (totaling 1,800 –2,800 + mm annually), but with a slightly drier period from March to June (Haynes & Bonta 2003).
Population structure: —This species occurs in small sporadic colonies of 12 or more plants (Haynes & Bonta 2003, Sandoval 2006). In a transect survey conducted within a protected area of the river basin, Sandoval (2006) estimated the total population of this species at around 77,000 plants at a mean density of nearly 100 plants per km². Because this estimate included a large proportion of seedlings (Sandoval 2006), the actual number of mature plants within the extent of occurrence could be an order of magnitude lower. The presence of cones of both sexes, seedlings, and juvenile plants suggests that the species is actively reproducing.
Biogeography: — Ceratozamia hondurensis, Zamia onan-reyesii, Z. oreillyii C. Nelson (2007: 42), and Z. sandovalii are all endemic to the North Coast of Honduras (Nelson Sutherland 2007, Haynes et al. 2008, Nelson Sutherland & Sandoval 2008). Zamia standleyi and Dioon mejiae also occur in the region, but this is the northernmost extent of their much more extensive ranges that extend to the south into the departments of Colón, Olancho, and Yoro (Haynes & Bonta 2003, Haynes 2007, Haynes & Bonta 2007). The likely sister species of C. hondurensis is C. euryphyllidia Vasq. Torres, Sabato & D.W.Stev. (1986: 17) (Chemnick 2005, Haynes et al. 2008), which occurs in Oaxaca and Veracruz, Mexico (Calonje et al. 2022); the likely sister species of Dioon mejiae are D. spinulosum (1883: 412) and D. rzedowskii De Luca, A.Moretti, Sabato & Vázq.Torres (1980: 225), which occur in Oaxaca and Veracruz, Mexico (Haynes & Bonta 2007, Calonje et al. 2022); and the likely sister species of Z. sandovalii are Z. cremnophila Vovides, Schutzman & Dehgan (1988: 351) and Z. lacandona Schutzman & Vovides (1998: 441) (see below), which occur in Chiapas and Tabasco, Mexico (Calonje et al. 2022)—thus the biogeographic link between the floristic refuges of southern Mexico and Honduras is herein strengthened to three cycad species groups in three genera (Chemnick 2005, Haynes & Bonta 2007, Pérez-Farrera et al. 2009).
Reproductive phenology: —Large, developing female cones (Fig. 1C, 1D) and remnants of spent male cones were observed in July (Haynes & Bonta 2003), and newly emerging female cones have been observed in November (Fig. 4) (S. Lavaud pers. comm.). Sprouting seeds and young seedlings with new eophylls were also observed in November (S. Lavaud pers. comm.), suggesting female cone dehiscence occurs between August and October.
Ethnobotany: —As with the other zamias of the North Coast of Honduras, this one is known locally as ‘camotillo’ (generic term for tuber) or ‘yuca de ratón’ (mouse manioc) (Bonta 2007, Nelson Sutherland 2007). Contrary to Zamia standleyi —widely known to be traditionally used for poisoning people as well as rodents—there is no evidence of local human uses for Z. sandovalii (Bonta 2007). It should be noted that the lack of ethnobotanical knowledge of this species comes from it not having been studied in detail; however, the name ‘camotillo’ suggests that uses may have existed for the plant (M. Bonta pers. comm.).
Pests: —Larvae of a hairstreak butterfly, Eumaeus toxea Godart (1824) (Lepidoptera: Lycaenidae), were observed feeding on a leaf of Zamia sandovalii in habitat (Fig. 5).
Threats: —Because plants of this species have a proclivity for growing along road cuts, certain populations may be relatively easy for collectors to find, while also being at risk from road improvement projects. Although the threat of deforestation is high throughout much of its limited range, the species’ saving grace may be its cliff-dwelling habit, as steep slopes tend to be the last areas impacted by migrant agriculture and cattle ranching in the region (Haynes & Bonta 2003, Bonta 2005).
Conservation status: — Zamia sandovalii occurs within two national parks on the North Coast (Haynes & Bonta 2003, Sandoval 2006, FAO 2022). However, based on its propensity to grow along road cuts, there is a constant threat of illicit collecting. This, combined with its limited range and the possibility of habitat degradation, the current Red List assessment is EN A3cd; B1ab(i–v)+2ab(i–v) (Bonta & Nelson Sutherland 2022).
description: Published as part of Haynes, Jody L. & Schutzman, Bart, 2023, Emended description of Zamia sandovalii (Cycadales: Zamiaceae), the cliff-dwelling cycad from Atlántida, Honduras, pp. 18-32 in Phytotaxa 584 (1) on pages 19-25, DOI: 10.11646/phytotaxa.584.1.2, http://zenodo.org/record/7624033