Ceratozamia delucana Vazq .Torres, A.Moretti & Carv.-Hern., Delpinoa 50-51: 129. 2013 ( "2008-2009" )

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

8. Ceratozamia delucana Vazq.Torres, A.Moretti & Carv.-Hern., Delpinoa 50-51: 129. 2013 ( "2008-2009")

Figs 2A, B , 10A, B , 15H

Type.

Mexico. Veracruz: Mun. Atzalan, road Atzalan- Tlapacoyan, 3 km NE from Atzalan , 20 Jan 2012, M. Va ́zquez-Torres & C. Carvajal-Herna ́ndez 10200 ♀ (holotype: CIB! [acc. # 13915UV]; isotypes: XAL [n.v.], XALU!) .

Description.

Stem 20-90 cm long, 25-40 cm in diameter, epigeous, erect and decumbent. Cataphylls 2-5.5 × 2.5-4.5 cm wide at the base, persistent, narrowly triangular, reddish brown, densely tomentose at emergence, partially tomentose at maturity, apex acuminate. Leaves 10-100, 106-223 cm long, ascending, yellowish green at emergence with brown trichomes, glabrous at maturity. Petiole 30-87 cm long, terete, linear, light green at mature leaves; with 35-76 thin prickles, 0.21-0.76 cm long. Rachis 60-150 cm long, terete, linear, green in mature leaves, with prickles. Leaflets 20-43 pairs, opposite to subopposite, insertion in one plane, lanceolate and oblong, longitudinally curved abaxially to planar, basally falcate to non-basally falcate, papyraceous to coriaceous, flat, green, adaxial side glaucous and glabrous and abaxial side glaucous, distal end with entire margins, acuminate and symmetrical to asymmetrical at the apex, attenuate at base, with conspicuous and light-green veins; median leaflets 22-45 × 2.3-4.6 cm, 1.5-5 cm between leaflets; articulations 0.6-1.6 cm wide, green. Pollen strobili 24-32 cm long, 5.5-7.6 cm in diameter, solitary, cylindrical, erect, greenish yellow at emergence, greenish yellow with blackish trichomes at maturity; peduncle 3.5-12.5 cm long, 1.3-2 cm in diameter, tomentose, reddish brown to light-brown; microsporophylls 1.5-2.5 × 1.3-2 cm, discoid and obconic with a non-recurved distal face and a lobate fertile portion, infertile portion 0.30-0.45 cm long and orbicular with straight horns 0.15-0.25 cm long, 0.40-0.60 cm and a right angle between the horns. Ovulate strobili 17-40 cm long, 10-13.5 cm in diameter, solitary, cylindrical and globose, erect, dark green with blackish trichomes at emergence, green, generally glabrous at maturity, acute apex; peduncle 5.2-15 cm long, 1.8-2.2 cm in diameter, erect and pendulous, tomentose, brown to reddish brown; megasporophylls 48-266, 7-14 orthostichies with 6-19 sporophylls per orthostichy, 2.2-4.2 × 3.4-4.5 cm, with a truncate distal face, horns straight and 0.45-0.72 cm long, 1.05-1.67 cm between horns with a right angle between the horns. Seeds 2.0-3 cm long, 1.35-2.1 cm in diameter, ovate, sarcotesta whitish yellow to yellow when immature, light brown at maturity.

Distribution and habitat.

Ceratozamia delucana occurs in Veracruz and Puebla States, Mexico (Fig. 16D ) and grows on karstic rocks in evergreen tropical forest at 500-1,650 m.

Etymology.

The epithet is in honor of Dr. Paolo De Luca, Professor at University of Naples Federico II and a researcher into the biology of Mexican cycads ( Vázquez-Torres et al. 2013).

Common names.

None recorded.

Uses.

None recorded.

Conservation status.

During the last 6 years, we have monitored the 6 populations for Ceratozamia delucana , in which no loss of individuals and regeneration has been observed. These populations are periodically producing ovulate and pollen strobili. The main problem is the loss of habitat in the central area of Veracruz, where there are no protected natural areas ( Martínez-Domínguez et al. 2021). These data suggest the category "Endangered (EN)" under (B1ab(iii)) criteria.

Discussion.

Ceratozamia delucana is highly variable and in vegetative morphology similar to C. morettii . However, there are clear differences in their ovulate strobili. In C. delucana , ovulate strobili are green and generally without trichomes at maturity and have an acute apex, whereas in C. morettii they are green with blackish trichomes at maturity and have an apiculate apex. Additionally, C. delucana is a larger plant than C. morettii , with C. delucana having leaves up to 223 cm long with up to 43 pairs of leaflets and ovulate strobili 17-40 cm long.

Specimens examined.

Mexico. Puebla: Mun. Hueytamalco , 520 m, 25 Feb 2008, G. Ibarra Manríquez et al. 5485 (MEXU, MO). Mun. Xochitlan de Vicente Suarez , 1,644 m, 9 Jun 2015, F. Nicolalde-Morejón & L. Martínez-Domínguez 2244, 2245 (CIB); 850 m, 25 Apr 1991, G. Villalobos & E. Guerrero C. 325 (MEXU); 1,644 m, 9 Jun 2015 , L. Martínez-Domínguez & F. Nicolalde-Morejón 587 - 616 (CIB). Veracruz: Mun. Atzalan , 1,400 m, 20 Feb 2013, F. Nicolalde-Morejón et al. 1740-1742 (CIB); 1,400 m, 16 Aug 2014, F. Nicolalde-Morejón et al. 2125 - 2144 (CIB); 1,400 m, 13 Mar 2015, F. Nicolalde-Morejón et al. 2168 (CIB); 1,400 m, 27 Oct 2008, L. Lagunes-Galindo et al. 153 (CIB); 1396 m, 28 Oct 2008, L. Lagunes-Galindo et al. 155 (CIB); 1,400 m, 16 Aug 2014, L. Martínez-Domínguez et al. 163 (CIB); 863 m, 13 Mar 2015, L. Martínez-Domínguez et al. 228 - 238 (CIB); 1,400 m, 13 Mar 2015, L. Martínez-Domínguez et al. 239 - 248 (CIB). Mun. Las Minas , 2 Jun 1979 , A.P. Vovides 427 (XAL); 1,500 m, 22 Sep 1988, C. Durán et al. 658 (XAL), 660 (MEXU, XAL); 1,500 m, 22 Sep 1988, C. Durán E. 659 (MEXU, XAL); 1,586 m, 20 Feb 2013, F. Nicolalde-Morejón et al. 1735 - 1739 (CIB); 1,621 m, 16 Aug 2014, F. Nicolalde-Morejón & L. Martínez-Domínguez 2107 - 2124 (CIB); 1,621 m, 16 Aug 2014, L. Martínez-Domínguez et al. 162 (CIB); 1,621 m, 18 Mar 2015, L. Martínez-Domínguez et al. 249-260 (CIB); 1 Mar 2005, 1,430 m, L.H. Bojórquez-Galván 1349 (CIB) ; 1,420 m, 16 Mar 2005, L.H. Bojórquez-Galván 1374 (CIB); 1,470 m, 28 Apr 2009, M. Vázquez-Torres et al. 8972 (CIB). Mun. Tlapacoyan , 900 m, 10 Jun 1970, Nevling & A. Gómez-Pompa 1083 (MEXU).

Figures

Figure 2. Characters evaluated in sporophylls A megasporophylls of Ceratozamia delucana B microsporophylls of C. delucana. HLMe = Horn length of megasporophylls; DHMe = Distance between horn of megasporophylls; AHMe = Angle between horns of megasporophylls; WMe = Width of megasporophylls; LMi = Length of microsporophylls; WMi = Width of microsporophylls; NMic = Number of microsporangia; LlpMi = Length infertile portion of microsporophylls; DHMi = Distance between horn of microsporophylls; HLMi = Horn length of microsporophylls.

Figure 10. Shapes and pubescence of cataphylls and stipules A from left to right: Ceratozamia latifolia, C. delucana, C. morettii at emergence and C. morettii at maturity B cataphylls of C. delucana C stipules of C. morettii D stipules of C. matudae.

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.