Microcycas Calocoma

A Publication of the Cycad Society Dedicated to the Conservation of Cycads through Education and Scientifi c Research Volume 30 Number 4 - December 2007 Conservation of Florida Coontie ......................... 22 Conservation Guidelines ................................... 36 In This Issue: Cycad Geometry: A Pictorial .............................. 24 Strange But True ............................................ 37 President’s Report/ Editor’s Message ..................... 2 Cycad Math 101 ............................................. 26 Lisbon Tropical Garden .................................... 38 Letters .......................................................... 3 Can All Cycads Do Math? ................................... 27 Eumaeus atala............................................... 40 14 Days in Mexico .............................................4 Mutualistic Relationships involving Cycas circinalis . 28 Sustainable Cycad Care .................................... 41 Scarifi cation of Cycad Seeds ................................9The CycadStudies ofNewsletter Cycads in Panama 30(4) .............................. December 2007 30 PageBiocontrols 1 and Biofertilizers ............................ 42 Cycad Focus: Microcycas calocoma ..................... 10 Rescuing Chigua ............................................. 34 Coffee: Cycads’ New Best Friend? ....................... 44 Focus Focus Microcycas Focus Cycad Focus calocoma Focus Some News of Microcycas in Cuba from developing a closed canopy, such rocks show on the surface, with most Article and Photos as those with rocky soils, steep slopes, plants occurring near the top of the hills by Ramiro Chaves & Yuriet Ferrer or fl uvial banks. This happens because of in semi-deciduous forest. The maximum its slow growth and resultant poor ability altitude of 665 msl reported for the spe- In the past, information about Micro- to compete for the sunshine it needs. Its cies occurs on one of these mountains cycas calocoma in its natural habitat has habitat is also restricted to places with (Risco et al. 1984). frequently come from outside sources, as enough humidity to allow seedlings to The fourth type of habitat is that of is frequently the case with information survive the dry season. the karstic (water-eroded calcareous) about Cuba itself. The commercial em- The species is present in four types of horst hills (called ‘mogotes’) of the los bargo of Cuba by the United States, the habitat with different relief structures, Organos mountain chain. The soils are largest cycad marketplace, has had a posi- soils, vegetation types and degrees of usually scarce and rocks emerge almost tive effect on Microcycas in one sense; its usefulness for agriculture or cattle. The continuously, which allows for groups of natural populations have been protected two best known habitats—and also the Microcycas to occur at short intervals as from illegal commercial exploitation dur- most modifi ed because of their easy ac- part of some of the variant shapes of the ing the same few decades in which there cess — are those of stream banks in the so-called Mogote Vegetation Complex. has been an explosive increase in demand higher plains of Consolación del Sur, and Their conservation in the latter mountains for cycads. Conversely, the embargo has ravines of the neighboring slate hills. In has been assisted by the nature of this also meant a lack of possibilities to fund the plains, Microcycas are part of relict rough habitat, which is diffi cult to access research on this species and fewer op- river forests that have been heavily al- and almost completely useless for agricul- portunities for researchers to travel out tered. In the slate ravines, they form part ture or cattle. of Cuba. In addition, visits to the nearby of semi-deciduous or river forests based island by American scientists and people on acidic soils and bordered by natural Prevalence in habitat interested in cycads are impeded by a forests of pine and Quercus or planted The Microcycas colonies referred by U.S. governmental prohibition on travel pine plantations. to Cuba. All these things have contributed A third habitat is to make Microcycas an enigmatic genus in the western part among cycads. of Sierra del Rosario. These mountains Habitat description are composed of a Microcycas calocoma grows naturally stratifi ed mixture only in Pinar del Río, Cuba’s westernmost of rocks creating a province. Its distribution range includes steep but not abrupt eight of the province’s fourteen town- relief. Microcycas ships, encompassing more than 1,400 km2. populations there The species is able to grow on a variety of are less known but soils. However, it can only thrive in loca- better conserved. tions where taller trees are prevented They grow where A karstic hill, one type of Microcycas habitat Microcycas locality at Granadinos The Cycad Newsletter 30(4) December 2007 Page 10 botanic literature are few. Up to 1998, E. Peña and other researchers of the Na- tional Botanic Garden of Cuba reported only 23 colonies with an estimated 800 to 1,000 plants (Peña et al. 1998). Neverthe- less, geographers and speleologists—who are the most frequent explorers of the Los Organos ranges—have documented the presence of more than 6,000 plants in at least 69 colonies (Carmenate, 2004). These data were collateral to their own expedition work, not the result of active searching. The region may therefore be home to more than double the number of specimens thus far reported. This and the rest of the mountainous regions in the species’ distribution range have extensive unexplored areas with possibilities to fi nd Microcycas. Pollination In 1998, Peña and her group also reported that natural pollination occurred only in 19 female plants, with reproducing females in only seven of the 23 known colonies (Peña et al., 1998). This reproductive limitation in many of the colonies was attributed to a decline or extirpation of the yet unknown insect pollinator. Old female Microcycas plant at El Sebo Microcycas in the Viñales National Park The Cycad Newsletter 30(4) December 2007 Page 11 Chaves and Genaro (2005) described but we did observe small plants up to fi ve km2 area occupied by known colonies, a probable insect pollinator named years old. the severely fragmented habitat, and the Pharaxonotha esperanzae (Coleoptera: Only 50% of the fresh dehiscent male continuing reduction in geographic area, Eriotilidae). It was found on a karstic hill cones examined in Viñales National Park habitat quality, and number of reproduc- within the Viñales National Park, which had adult Pharaxonotha esperanzae pres- tive females. The total number of repro- contains about 1,000 Microcycas plants ent. This and their low presence per cone ductive females was also estimated by distributed in numerous closely-spaced are dissimilar to what has been described Peña (1998) to be fewer than 250; these groups, where young plants are abundant for pollinators of this beetle genus in were also reported to be actively declin- and seed production occurs annually. The other cycads. Pharaxonotha pollinators in ing in number and with no more than 50 probable function for this insect is based Ceratozamia are described as abundant, reproductive females in any individual on the fact that it is of the same genus with up to 5,300 adults per male cone colony. Data from newly discovered colo- and with the same behaviors as some of (Vovides, 1991). Almost every receptive nies remain to be analyzed, but overall those that pollinate species of three other male cone of Zamia fl oridana in habi- they do not seem to justify changing its New World cycad genera (Ceratozamia, tat in Florida is found to have a few to classifi cation. Dioon and Zamia) (Vovides, 1991; Tang, several dozen individuals of the pollina- Ethnobotanic issues 2004). Besides, this is the only fl ying tor Pharaxonotha fl oridana (Tang 1987). We think the arguments given by other insect with repeated presence at the Based on the common presence of pollina- authors regarding the etymology of the right moment to carry pollen from male tors in male cones that are much smaller common name ‘palma corcho’ or ‘corcho’ to female cones—although it has not yet than those of Microcycas, one would (cork) are illogical and lack merit. Seeds been observed on female cones to certify expect to see exceedingly larger numbers its role in pollination. of pollinators in the larger cones. Sadly, This little insect was scarcely observed this is not the case. by Chaves and Genaro (2005)—only an All of these things make us suspect average of 13 adults per male cone—so no that pollinators are declining in the region further work was conducted to search for of endemicity. Furthermore, although them on female cones. We can now show there is evidence of annual pollination, new data to uphold the probable pollina- only about half of the female cones set tion function of this insect. First, it was seed, and then only in small quantities. absent in male cones that we examined Conservation status from the colonies of Loma Granadinos, Microcycas was classifi ed as critically Cayo Ramones, and Barrabás. These are endangered in 1998 by Peña and her col- some of the colonies described by Foster laborators, based on the estimated 10 and Rodriguez San Pedro (1942) as lacking natural seed production for many years and which still fail to set seed. Con- versely, this year we found Pharaxonotha esperanzae in a male cone in the colony of Forneguera, which is located at the Mil Cumbres Protected Area of Managed Re- sources and contains about 87 Microcycas plants. This colony was reported in 1988 as having seed production (Peña et al., 1988). This year we did not fi nd seeds, LargeL coningi microsporangiatei i Large Microcycas calocoma plant at Old trunk of Microcycas calocoma Microcycas calocoma plant at Maceo Managuaca growing along a stream bank with its persistent armor of leaf bases The Cycad Newsletter 30(4) December 2007 Page 12 have neither the form nor the appearance ness and soft texture as compared to crocycas roots were once used as rat of a bottle cork, as stated by Caldwell those of a cork, as later stated by Foster poison in some of the zones of Sierra del (1907).

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