Ceratozamia euryphyllidia Vazq .Torres, Sabato & D.W.Stev., Brittonia 38(1): 17. 1986

Martinez-Dominguez, Lili, Nicolalde-Morejon, Fernando, Vergara-Silva, Francisco & Stevenson, Dennis Wm., 2022, Monograph of Ceratozamia (Zamiaceae, Cycadales): an endangered genus, PhytoKeys 208, pp. 1-102 : 1

9. Ceratozamia euryphyllidia Vazq.Torres, Sabato & D.W.Stev., Brittonia 38(1): 17. 1986

Fig. 15I

Type.

Mexico. Veracruz: Mun. Minatitlán, 21 Jun 1984, M. Vázquez-Torres 2842 ♀ (holotype: NY! [acc. # 1157-1166]; isotypes: CHAPA [n.v.], NY! [♂ acc. # 00001167- 00001173], XALU [n.v.]) .

Description.

Stem 25-50 cm long, 8-15.3 cm in diameter, semi-hypogeous, erect and decumbent. Cataphylls 4.5-7 × 4.2-7.5 cm wide at the base, persistent, triangular, reddish brown, densely tomentose at emergence, glabrous at maturity, apex acute. Leaves 2-22, 95-337.5 cm long, ascending, light green, glaucous at emergence, with whitish gray trichomes, glabrous at maturity. Petiole 40-193 cm long, terete, linear, green to yellowish (pink in new leaves); with 8-35 thin prickles, 0.13-0.50 cm long. Rachis 53-218.5 cm long, terete, linear, green to yellowish in mature leaves, with prickles. Leaflets 6-17 pairs, opposite to subopposite, insertion in one plane, broadly obovate, in general longitudinally planar, not basally falcate, membranaceous, flat, green with adaxial and abaxial sides glabrous, distal end with sinuate margins, acuminate and asymmetrical at the apex, attenuate at base, with prominent and light-green veins; median leaflets 19.9-35.7 × 8.5-17.6 cm, 9-22 cm between leaflets; articulations 0.9-1.4 cm wide, yellow and green. Pollen strobili 27-35 cm long, 3-4.3 cm in diameter, solitary, cylindrical, erect, greenish yellow with reddish trichomes at emergence, greenish with black trichomes at maturity; peduncle 6-12 cm long, 1.5-2 cm in diameter, tomentose, reddish brown to brown; microsporophylls 1.0-1.5 × 0.5-1.3 cm, discoid with a non-recurved distal face and a lobate fertile portion, infertile portion 0.37-0.45 cm long and orbicular and rounded with straight horns 0.35-0.50 cm long, 0.60-0.72 cm and an acute angle between the horns. Ovulate strobili 15-20 cm long, 5-6 cm in diameter, solitary, cylindrical, erect, yellowish green to green with abundant, deep red trichomes at emergence, greenish brown with abundant, dark reddish brown trichomes at maturity, acuminate apex; peduncle 5-11.5 cm long, 1-2.5 cm in diameter, erect, tomentose, light brown; megasporophylls 35-64, 1.5-3 × 1.2-1.8 cm, 7-8 orthostichies with 5-8 sporophylls per orthostichy, 2.0-4.0 × 2.8-3.4 cm wide, with a truncate distal face, horns straight and 0.60-0.80 cm long, 0.99-1.40 cm between horns with an acute angle between the horns. Seeds 2.3-2.5 cm long, 1.5-1.7 cm in diameter, ovate, sarcotesta whitish red when immature, light brown at maturity.

Distribution and habit.

Ceratozamia euryphyllidia is endemic to the forest of Uxpanapa-Chimalapas in Oaxaca and Veracruz States, Mexico (Fig. 17A ) where it inhabits evergreen tropical rain forest on clay soils at the top and sides of hills between 100 and 630 m elevation.

Etymology.

The specific epithet represents the very wide, diagnostic leaflets of this species. It comes from the Greek euryphyllos, which means, "wide leaflet".

Common names.

None recorded.

Uses.

None recorded.

Conservation status.

( IUCN 2021). Ceratozamia euryphyllidia is listed as "Critically Endangered (CR)" under criteria B2ab(i,ii,iii,iv,v). We carried out a census in two populations for this species, in which we found between 20 to 60 adult plants. The population in Veracruz has reproductive plants, juvenile and seedlings; however, it is a small population and the surrounding area has been transformed to anthropogenic landscapes. We suggest that this status should be maintained.

Discussion.

Ceratozamia euryphyllidia is easily diagnosable from its congeners in Mexico by its broadly obovate, lustrous and membranaceous leaflets asymmetrical apex of leaflets. Also, the ovulate strobili are greenish brown with an acuminate apex, and its megasporophylls are green with abundant dark brown trichomes. This species is most similar to C. hondurensis , but it can be distinguished by its sinuate margins at distal end of leaflets, whereas in C. hondurensis they are entire.

Specimens examined.

Mexico. Veracruz: Mun. Minatitlán , 100 m, 24 Jul 1986, A.P. Vovides & E.R. Acosta 1108 (MO, XAL); 21 Jun 1984, M. Vázquez-Torres 1157 (NY). Mun. Jesús Carranza, 24 May 1982, M. Vázquez-Torres 2532 (CIB, MEXU); 26 Mar 1982, M. Vázquez-Torres et al. 2374 (CHAPA, MEXU, NY); 100 m, 5 Jun 1989, M. Vázquez-Torres & J.P. Sclavo 4037 (CIB); 18 Apr 1982, M. Vázquez-Torres 2451 (CHAPA, MEXU, MO, NY); 120 m, 28 Jul 1983, M. Vázquez-Torres 2614 (CIB, NY); 21 Jun 1984, M. Vázquez-Torres 4126 (NY); 120 m, 28 Dec 1984, T. Wenth et al. 4732 (CHAPA). Mun. Uxpanapa, 398 m, 18 Mar 2014, F. Nicolalde-Morejón & L. Martínez-Domínguez 1984 (CIB); 19 Mar 2014, L. Marti ́nez-Domínguez & F. Nicolalde-Morejo ́n 71-77 (CIB). Mun. Hidalgotitla ́n (plant cultivated at JBC-INECOL), V.E. Luna M. 1520 (XAL). Oaxaca: Mun. Santa Mari ́a Chimalapa , 232 m, 13 May 1995, E. Torres B. 687 (SERO, XAL); 398 m, 18 Mar 2014, F. Nicolalde-Morejón & L. Martínez-Domínguez 1982, 1983 (CIB); 335 m, 5 May 1996, J.E. Rivera H. & S. Escobedo 102 (XAL); 630 m, 16 May 1998, J.E. Rivera H. et al. 700 (MEXU); 475 m, 21 Mar 1999, J.E. Rivera H. et al. 1195 (SERO); 398 m, 18 Mar 2014, L. Martínez-Domínguez & F. Nicolalde-Morejón 51-70 (CIB).

Figures

Figure 15. Plants of Ceratozamia in habitat A C. alvarezii B C. aurantiaca C C. becerrae D C. brevifrons E C. chamberlainii F C. chimalapensis G C. decumbens H C. delucana I C. euryphyllidia J C. fuscoviridis K C. hondurensis L C. huastecorum.

Figure 17. Distribution of Ceratozamia species A C. euryphyllidia B C. fuscoviridis C C. hildae D C. hondurensis.