A New Species of Ceratozamia () from Veracruz, Mexico

Mario Vázquez-Torres Instituto de Investigaciones Biologicas, Universidad Veracruzana, Apdo. Postal 294 Xalapa, Veracruz, 9100 Mexico

Andrew P. Vovides Instituto de Ecología, A.C., Apdo. Postal 63, Xalapa, Veracruz, 91000 Mexico

ABSTRACT. Ceratozamia morettii is described cm long, 1 cm diam., reddish brown tomentum; mi- from a cloud-forest environment in Veracruz, Mex- crosporophylls cuneate, 10-12 mm long, 8-9 mm ico. The main morphological characters are illus- wide, distal end with two erect to curved prominent trated, and comments on related species are made. coniform protuberances; microsporangia numerous, 1 2 The new species differs from others in the genus generally in sori of three covering /2 to /3 of abaxial by the near prostrate habit, circinate vernation of surface, dehiscence longitudinal; megastrobilus the , and wide leaflets with translucent ve- coniform, green when juvenile turning brown at ma- nation. This taxon is apparently related to a group turity, 12—16 cm long, 4.5—5 cm diam.; peduncle of species that are relatively small trunked, terete, dark brown tomentose, 5-7 cm long, 1 cm branched, produce few leaves, and have relatively diam.; megasporophylls peltate, reddish brown, dis- small strobili. The non-sympatric species of the tal end almost hexagonal with two erect or curved group also inhabit moist to very moist habitats, as corniform protuberances; ovules ovoid, two per in the case of C. miqueliana, C. microstrobila, and megasporophyll; seeds irregularly ovoid without any C. mexicana var. robusta. defined faces, sarcotesta yellowish white when im- mature turning to gray brown, delicately papyra- Ceratozamia morettii Vázquez-Torres & Vovides, ceous and transparent when mature, sclerotesta sp. nov. TYPE: Mexico. Veracruz: 7 Jan. 1992, hard, light gray, 1.5—1.8 cm long, 1.2 cm diam.; M. Vázquez-Torres & H. Barney 4097 (holotype, chromosome number 2n = 16. CIB; isotypes, CIB, MEXU, XAL). Figure 1. CHROMOSOMAL STUDIES Truncus semihypogaeus. humilis ad 30 cm altus; folia vernata circinata, pauca. usque 10, glabra. Foliola subop- The chromosome number and karyotype of Cer- posita vel alterna, 12-25 juga, remota, linearis vel falcata. atozamia morettii were determined from three es- translucida, tenuia. basicuneata. tablished specimens held at the Jardin Botánico palm-like, trunk erect to procumbent, Fco. J. Clavijero (Botanic Garden of the Instituto short, globose to cylindrical, semihypogeous up to de Ecología) under the accession numbers 81-397, 30 cm long, 8 cm diam., typically with 1—4 branch- 81-857, and 81-852; vouchers are deposited at es covered with persistent cataphyll and bases; XAL. The root tip mitosis technique used was that cataphylls triangular, 2 cm wide at base, 2.6 cm described by Vovides (1983), and the chromosome long; vernation circinate; leaves light green, classification based on centromere position was that pubescent when juvenile, decurrent to prostrate of Levan et al. (1964) modified by Schlarbaum and forming an open crown with a maximum of 10(4— Tsuchiya (1984). The diploid idiogram (Fig. 2) was 7) leaves per crown, 1-1.4 m long, 40-65 cm wide; constructed by taking the average arm lengths of leaflets 12—25 pairs, ovoid when immature, becom- the best three metaphase cells examined (Fig. 3). ing linear to falcate upon maturity, chartaceous, ve- Photomicrography was done on a Zeiss photomicro- nation parallel, translucid, pale yellow, dichotomous scope (Fomi III) equipped with phase contrast op- principally in the lower third of leaflet, 25-35 cm tics and planapochromatic objectives. Prints were long at median position of leaf, distal portion un- made using Kodak bromide paper. Arm lengths, to- evenly sinuous, apex acute, base attenuate, 2.7—4.8 tal chromosome length, chromosome index (short cm wide, pctiole terete or subterete, 45-60 cm arm divided by long arm), and symmetry index long, armed with short stout prickles; microstrobilus (length of longest pair divided by length of shortest typically coniform, elongate, yellowish green, 10- pair) were computed using the average arm lengths 15 cm long, 2.5-4 cm diam.; peduncle terete, 5-7 from the three metaphase cells (Table 1). The

NOVON 8: 87-90. 1998. 88 Novon

Figure 1. a—i, Ceratozamia moretii Vázquez-Torres & Vovides. —a. Habit of plant. —b. Circinate vernation of leaf, , and trunk. —c. Leaflet articulations and rachis. —d. Detail of leaflet veins. —e. Non-expanded male strobilus. —f. Abaxial view of microsporophyll showing dehisced sporangia. —g. Female strobilus. —h. Megasporophyll with immature ovules. — i. Seed. Volume 8, Number 1 Vázquez-Torres & Vovides 89 1998 Ceratozamia morettii from Mexico

Figure 2. Diploid idiogram of Ceratozamia morettii (2n = 16). bar = 2 µm. .

karyotype shows 12 median region (m) chromo- somes, 1 submedian (sm), 1 sub-terminal region (st) chromosome, and 2 terminal point (T) chromo- somes. A maximum of 5 satellites were recorded but were not considered in the calculations.

HABITAT This occurs in cloud forest on humus-rich grayish yellow clay soil of volcanic origin. The are found on steep 45—60° slopes or on ver- tical rocky walls of loose, weathered basalt, at an elevation of 1200 to 1400 m. The closest climato- logical station to this habitat has recorded an av- erage temperature of 17.3°C and over 1900 mm Figure 3. Mitotic metaphase cell of Ceratozamia moret- annual precipitation. tii, bar = 4 µm. Other vascular plants associated with the cycad in this vegetation type are typical of cloud-forest species distributed on the windward slopes of the nolia schiedeana Schlechtendal, Marattia laxa Sierra Madre Oriental facing the Gulf of Mexico. Kunze, Oreopanax capitatus (Jacquin) Decaisne & These are: Alnus jorullensis Kunth, Clethra mexi- Planchon, Ostrya virginiana (Miller) K. Koch, Po- cana DC, Dendropanax arboreus (L.) Decaisne & docarpus guatemalensis Standley, Quercus germana Planchon, Dicksonia gigantea Maxon, Ilex discolor Chamisso & Schlechtendal, Q. laurina Humboldt Hemsley, Liquidambar macrophylla Oersted, Mag- & Bonpland, Q. xalapensis Humboldt & Bonpland,

Table 1. Karyotypic data at metaphase in root-tip mitosis of Ceratozamia morettii (mean of three metaphase cells).

* m = median, msm = median-submedian, sm = submedian. st = subterminal. T = terminal. Average chromosome index = 0.70. 90 Novon

Turpinia insignis (Kunth) Tulasne, and Ulmus mex- 2b. Persistent leaf bases light brown, tightly ap- icana (Liebmann) Planchon. presseci to trunk. 7a. Leaflets pinnate, elliptic to lanceolate C. microstrobila DISCUSSION 7b. Leaflets fasciculate, lanceolate . . C. hildae

The specific epithet was chosen in recognition of The chromosome count and karyotype are con- the scientific contributions of Aldo Moretti in the sistent with that reported for the genus (2n = 16) field of cycad biology. Prof. Moretti is a researcher by Marchant (1968), Vovides (1983, 1985), Vovides of the Orto Botanico of the University of Naples, et al. (1993), and Moretti (1990). The karyotype of Italy. C. morettii (12m + 1sm + 1st + 2T) is nearly Ceratozamia morettii differs from the rest of its typical for the genus Ceratozamia (12m + 2sm + congenere by the circinate vernation of its leaves. 2T) and appears to be stable within the genus (Vo- Like C. microstrobila, C. morettii has few nearly vides et al., 1993; Moretti, 1990). Satellite number prostrate leaves per crown and profuse branching and position appear to vary with cells observed and of the trunk. Ceratozamia morettii belongs to the much care is needed in recording them. A maxi- group of species having wide leaflets: i.e., C. eu- mum of five were recorded and many cells showed ryphyllidia Vázquez-Torres, Sabato & Stevenson, C. three. microstrobila Vovides & Rees, C. hildae Landry & The precise locality has been intentionally omit- Wilson, C. miqueliana H. Wendland, C. latifolia ted to discourage indiscriminate commercial col- Miquel, C. mexicana var. robusta (Miquel) Dyer, lecting of this endangered species, which could re- and C. whitelockiana Chemnick & Gregory. With sult in its extinction. The common nmes of this the exception of C. microstrobila, C. hildae, and species are "tepetmaizte," or "tepemaizte" (forest perhaps C. mexicana var. robusta, the other taxa maize), because of a similarity between the corn- are distributed south of the neovolcanic belt of cob and the cycad cones. Mexico in moist habitats. Acknowledgments. We thank Manuel Escamilla The following key separates Ceratozamia morettii for the botanical illustration of this species. This from other Ceratozamia species with wide leaflets. research was partially funded by CONACyT pro- jects No. 0063-N9106 and 1837P-N9507, LE. Sis- DIACNOSTIC KEY temática Vegetal project No. 904-14 and U.V. F641-M940. la. Emerging leaves presenting circinate vernation, leaves spreading, leaflets ovoid when immature, linear, falcate to subfalcate, not greater than 5 Literature Cited cm wide C. morettii Levan, A., K. Fredga & A. A. Sandberg. 1964. Nomen- 1b. Emerging leaves not presenting circinate verna- clature for centromeric position on chromosomes. Her- tion, leaves ascending or spreading, leaflets lan- editas 52: 201-220. ceolate, elliptic, obovate, or broadly oblanceo- Marchant, C. J. 1968. Chromosome patterns and nuclear late. phenomena in the cycad families Stangeriaceae and Za- 2a. Persistent leaf bases dark brown, not ap- miaceae. Chromosoma (Berl.) 24: 100-134. pressed to trunk. Moretti, A. 1990. Karyotypic data on north and central 3a. Leaflets coriaceous. American Zamiaceae (Cycadales) and their phylogenet- 4a. Leaflets lanceolate, less than 4 cm ic implications. Amer. J. Bot. 77: 1016-1029. wide C. mexicana var. robusta Schlarbaum. S. E. & T. Tsuchiya. 1984. The chromosomes 4b. Leaflets not lanceolate. of Cunninghamia konishi, C. lanceolata and Taiwania 5a. Leaflets obovate to broadly ob- cryptomeroides (Taxodiaceae). Pl. Syst. Evol. 145: 169— lanceolate, greater than 4 cm 181. wide C. miqueliana Vovides. A. P. 1983. Systematic studies on the Mexican 5b. Leaflets elliptic to oblanceo- Zamiaceae I. Chromosome numbers and karyotypes. late, less than 4.5 cm wide . . Amer. J. Bot. 70: 1002-1006. C. latifolia . 1985. Systematic studies on the Mexican Zami- 3b. Leaflets papyraceous. aceae II. Additional notes on Ceratozamia kuesleriana 6a. Leaflets linear lanceolate, less than from Tamaulipas, Mexico. Brittonia 37: 226-231. 4 cm wide C. whitelockiana , M. Vázquez-Torres, B. Schutzman & C. G. Igle- 6b. Leaflets broadly oblanceolate, sias. 1993. A new species of Ceratozamia (Zamiaceae) greater than 8 cm wide from Querétaro and Hidalgo, Mexico. Novon 3: 502— C. euryphyllidia 506.