Ceratozamia chamberlainii Mart.- Dominguez , Nic.-Mor. & D.W.Stev., Phytotaxa 317(1): 22. 2017

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

5. Ceratozamia chamberlainii Mart.- Dominguez, Nic.-Mor. & D.W.Stev., Phytotaxa 317(1): 22. 2017

Figs 3C , 15E

Type.

Mexico. San Luis Potosí: Mun. Xilitla, 1,044 m, 20 Mar 2016, L. Martínez-Domínguez et al. 933 ♀ (holotype: CIB! [acc. # 17766UV]; isotypes: MEXU! [MEXU1492226, MEXU1492227, MEXU14922278], NY!) .

Description.

Stem 20-60 cm long, 15-30 cm in diameter, epigeous, erect and decumbent. Cataphylls 2.5-5.5 × 1.5-3.5 cm wide at the base, persistent, narrowly triangular, reddish brown, densely brownish tomentose at emergence, glabrous at maturity, apex acuminate. Leaves (5)10-40, 100-207 cm long, descending, reddish brown at emergence with whitish gray trichomes, glabrous at maturity. Petiole 30-69 cm long, terete, linear, blackish brown in mature leaves; with 9-30 robust prickles, 0.03-0.30 cm long. Rachis 65-144 cm long, terete, linear, reddish brown in mature leaves, with prickles. Leaflets 20-42 pairs, opposite to subopposite, insertion in one plane, oblong, longitudinally curved abaxially to planar, not basally falcate, coriaceous, flat, dark green with adaxial and abaxial sides glabrous, distal end with entire margins, acuminate and asymmetric at the apex, attenuate at base, with conspicuous and reddish brown veins; median leaflets 20-37 × 2.3-4 cm, 1.6-3.5 cm between leaflets; articulations 0.5-1.3 cm wide, generally reddish brown. Pollen strobili 20-31 cm long, 4.5-6 cm in diameter, generally solitary (1-2), cylindrical, erect, greenish brown at emergence with reddish trichomes becoming greenish with reddish brown trichomes at maturity; peduncle 5.2-8.1 cm long, 1.6-2.3 cm in diameter, reddish brown pubescent; microsporophylls 1.6-2.3 × 0.9-1.5 cm, obconic with a non-recurved distal face and a deeply lobate fertile portion, infertile portion 0.44-0.55 cm long and linear with curved horns 0.25-0.40 cm long, 0.40-0.80 cm and an acute angle between the horns. Ovulate strobili 25.5-30 cm long, 7.5-10.5 cm in diameter, cylindrical, erect, greyish green with reddish brown trichomes at emergence and becoming light grayish brown with reddish brown trichomes at maturity with an acuminate apex; peduncle 4.5-11.5 cm long, 1.3-2.5 cm in diameter, erect, tomentose, brown to reddish brown; megasporophylls 49-180, 7-12 orthostichies with 7-15 sporophylls per orthostichy, 2.0-3.0 × 2.3-4.0 cm, with a prominent distal face, horns straight and 0.40-0.80 cm long, 2.0-2.70 cm between horns with an acute angle between the horns. Seeds 2.2-3.5 (4) cm long, 0.6-1.7 cm in diameter, ovate, sarcotesta whitish red to pink when immature, light brown at maturity.

Distribution and habitat.

Ceratozamia chamberlainii is distributed in the northern montane region of Carso Huasteco in San Luis Potosí, Querétaro and Hidalgo States, Mexico (Fig. 16A ), where it occurs in cloud forest and pine-oak forest on rocky outcrops between 900-1,200 m.

Etymology.

The specific epithet is in honor of Charles Joseph Chamberlain in recognition of his remarkable contributions to knowledge of the biology of the cycads and his fieldwork on Mexican Cycads ( Martínez-Domínguez et al. 2017a).

Common names.

Mexico. San Luis Potosí: Chamal (A.P. Vovides 1288), chamalillo (H. Puig 3979); Hidalgo: teocintle (A. Vite-Reyes et al. 23).

Uses.

None recorded.

Preliminary conservation status.

According to the IUCN criteria, the data suggest "Endangered (EN)". Ceratozamia chamberlainii is included in Biosphere Reserve Sierra Gorda and have 9 populations recorded by us with several adult plants, juveniles and seedlings.

Discussion.

Ceratozamia chamberlainii is close geographically and morphologically to C. fuscoviridis and C. latifolia ; however, it differs by its petioles and rachis bearing abundant and short prickles, and its oblong and coriaceous leaflets with conspicuous, reddish brown veins. In addition, the leaves are reddish brown at emergence and at maturity have this color in the leaflet articulations and at the base of leaflets in contrast to the yellowish to greenish articulations in C. fuscoviridis and C. latifolia .

Specimens examined.

Mexico. Hidalgo: Mun. Chapulhuacan , 1,500 m, 21 Feb 1998, Alcántara-Ayala 3650 (FCME); 8 Jan 2009, A. Vite-Reyes et al. 23 (XAL); 1,157 m, 30 Mar 2015, F. Nicolalde-Morejón et al. 2200 - 2203 (CIB); 20 Sep 1964, L. González-Quintero 4634 (ENCB); 1,157 m, 30 Mar 2015, L. Martínez-Domínguez et al. 429 - 454 (CIB). Mun. La Mision , 1,120 a 1,400 m, 5 Oct 2007, A. Castro-Castro et al. 1017 (IBUG, XAL); 7 Jan 2009, A. Vite-Reyes et al. 20 (XAL). Querétaro: Mun. Landa de Matamoros , 1,050 m, 28 May 1999, A.P. Vovides 1288, 1289, 1290, 2000 (XAL), 1291 (XAL, MEXU); 2 Apr 1991, E. Carranza 6333 (IEB); 940 m, 2 Apr 1991, 3119 (MEXU); 1,335 m, 30 Mar 2015, F. Nicolalde-Morejón et al. 2192 - 2197 (CIB); 1,145 m, 30 Mar 2015, F. Nicolalde-Morejón et al. 2198, 2199 (CIB); 1,335 m, 30 Mar 2015, L. Martínez-Domínguez et al. 379 (CIB, MEXU), 380- 407 (CIB); 1,145 m, 30 Mar 2015, L. Martínez-Domínguez et al. 408-428 (CIB); 1,070 m, 9 May 1989, R. Hiram 647 (XAL). San Luis Potosí: Mun. Aquismon , 600 m, 10 Feb 1969, H. Puig 3979 (ENCB, P); 27 May 1979, J.A. Alcorn 3093 (MEXU); 1,125 m, 9 Jun 2015, T. Diego-Vargas & M. Bonta 35 (XAL). Mun. Tamazunchale , Jul 1952, A. Wilson 273, 274 ( US) ; Jul 1937, C.L. Lundell & A.A. Lundell 7235 (CIB, IEB) ; 600-900 m, 29 Jun 1959, J. Rzedowski 11087 (ENCB). Mun. Xilitla , 1,044 m, 20 Mar 2016, F. Nicolalde-Morejón et al. 2407 - 2420 (CIB); 1,044 m, 20 Mar 2016, L. Martínez-Domínguez et al. 924 - 932, 934 - 937 (CIB), 938 (CIB, MEXU), 939 (CIB); 1,948 m, 12 Jan 2001, T.W. Walters, TW-2001-04-A,B (XAL), TW-.2001-04-C (MEXU).

Figures

Figure 3. Comparison of qualitative characters of microsporophylls A Ceratozamia fuscoviridis B C. brevifrons C C. chamberlainii D C. kuesteriana.

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 16. Distribution of Ceratozamia species A C. chamberlainii B C. chimalapensis C C. decumbens D C. delucana.