Chromosome Studies of Brazilian

Alice F. Tryon (1) Hortensia P. Bautista (2) lzonete da Silva Araújo (3)

Abstract cent paper by Britton (1974) which summarizes tho work in cytology and indicates they Chromosome numbers, habitat and general geo­ graphic distributions are reported for a sample of are rather well sampled except for those of ferns from the vicinity of Manaus. These numbers South /\merica and mainland China. The are compared with those reported for species in opportunity to include a section on cytology in other regions. The report of n=ca. 154 for Schi­ the Class of Pteridophyta, taught during Sep­ za.ea incurvata is the first record of the genus in tember and October 197 4, as part of the Cur­ the American tropics and the others are first counts of these species in continental South America. In so de Botânica Tropical do Instituto Nacional Lindsaea n=42 and n=ca. 84, are somewhat lower de Pesquisas da Amazônia was taken to begin and appear to represent a line distinct from the work with Brazílian students. We hope that species of the paleotropics with n=47. In Tricho­ this sample of our accomplishments over a manes n=32, 64 and 128 appear to be levels of po­ relatively brief period will motivate further lyploidy based on X= 8, while n=72 is possibly ba­ sed on X = 9 and suggest possible diverse lines in studies in the Amazonian area and in other the genus. Pityrogramma calomelanos with n=ll6 parts of South America. is considered as an octoploid based on X= 29 . Our sample cov~ring about ten percent of the pterido­ phytes in the area we collected, yielded numbers MATERIALS AND METHODS ranging between n=32 and n = 154, and generally appears to represent high polyploid levels. Leaves with young sporangia were fixed in Farmer's solution consisting of 1 part gla­ cial acetic acid to 3 parts absolute alcohol. The American tropics has one of the Some material fixed in 96% alcohol softened, world's richest fern floras encompassing some for example, see Fig. 10 of pilo­ 4000 species, but cytologically it is poorly sum, and the chromosomes are not well­ known. Cytological surveys of pteridophytes spread. The si ides were prepared by removing were initiated with studies centering on the sporangia from the leaves into a drop of fixa­ British species by Manton (1950) and were tive. A drop of aceto-carm i ne was added after soon extended to many regions as lndia, Cey­ the solution evaporated; the slide was then lon, Japan, West Africa, New Zealand and heated over an alcohol lamp, and squashed. eastern North America. The most comprehen­ Preparations were made permanent by inver­ sive study of American species is the survey ting t he slides on glass rods in 95% alcohol, of Jamaican ferns by Walker (1966) w hich en­ untíl the cover glass dropped, and mounting campasses 270 of some 540 species listed for in Diaphane. the island. This is a major col'ltribution to the subject and the most useful reference for our Meiotic f igures obtained in eleven species work. There are essentially no cytological in­ are illustrated and discussed in this paper. vestigations of t he ferns of continental South Collections were made at four localities in the America. This point is clearly made in a re- vicinity of Manaus- at the Instituto Nacional

( 1} ~ Gray Herbarium, Harvard University, Cambridge, Massachusetts 02138. ( 2) - INPA, Museu Paraense Emílio Goeldi, Belém. Bolsista do CNPq. ( 3} - Instituto Nacional de Pesquisas da Amazônia, Manaus. Bolsista do CNPq.

ACTA AMAZONICA 5(1):35-43. 1975 -35 de Pesquisas da Amazônia (INPA), at the Re­ 130 on the Manaus to Caracaraí road. Perma­ serve Florestal Ducke (km 26), on the Manaus nent slides and herbarium vouchêrs- are depo­ to ltacoatiara road, at the Estação Experimen­ sited at the Gray Herbariurn, Harvard Univer­ tal de Silvicultura Tropical (km 60), and at km sity.

Schizaea Species, voucher Meiotic number General Distribution S. incurvata Schkur ca. 154 Guianas, Amazonian, Brazil, Upper Orinoco INPA, Conant 1103 and Gran Sabana, Venezuela, Vaupés, Manaus. Colombia.

This is one of the two species of Schizaea species of t he Polypodiaceae in which there frequent on the open, white sandy campina usually are only 16 spore mother cells per areas that are interspersed arnong the forests, spomngium. In this material of Schizaea the near Manaus. This and S. pennula Sw. form chwmosomes were easily spread, and meiosis l<:1 rge colonies in open sunny places or often appears to be synchronized with numerous arn ong shrubs at the edge of the forest. The nuclei in different phases of diakinesis within sterile leaves of both species are filiform, a single sporangium. characteristic of a group of species in Schi­ fhe chromosome number in Schizaea in­ zaea, but the fertile ones are quite distinct. curvata is clearly polyploid although the levei The fertile segments of S. incurvata are atta­ is difficu lt to establish. The lowest number ched laterally to a central rachis and are often reported for the genus is n= 77 in S. asperula conduplicate as in Fig. 1. Those of S. pennula Wakefield, from New Zealand. The same num­ are clustered at the petiole apex in a tufted ber is reported in S. dichotoma (L.) Smith, from arrangement. Ceylon while another specimen of the species, This report of ca. 154 in Schizaea incur­ from New Zealand is reported as n= 540. This vata (Fig. 2). the first cytological record of the large number of chromosomes approaches genus for the American tropics, is relatively that in Ophioglossum reticulatum L., from In­ high for the pteridophytes. There are some dia which is illustrated by Ninan (1958) with pt·oblerns in working with such high numbers n= 630, the largest nurnber of chromosomes of chromosomes but there are also cornpensa­ reported for any living organism. lt is interes­ tions in these . They have large sporan­ ting to note that the leaf form in Schizaea is gia with many more megasporocytes than in a simple one as it is in Ophioglossum.

Trichomanes Species, voucher Meiotic number General Distribution T. arbuscu/a Desv. ca. 128 Guianas, Amazonian Brazil, Bolivar and km 130, Bautista + Araújo 14 Amazonas, Venezuela, Vaupés, Colom­ bia T. crístatum Kaulf. 72 Guianas south to Bo livia and Rio Grande km 60, Bautista + Araújo 22 do Sul, Brasil T. elegans Rich. 32 Guianas south to Peru and Santa Catarina, Ducke, Bautista + Araújo 4 Brazil, Jamaica, Hispaniola and Lesser Antilles T. pilosum Saddi ca. 62-68 Guianas, Bolivar, Venezuela south to Peru km 130, Bautista + Araújo 20 and Uruguay T. tanaicum Hook. 32 Arnazonian Brazil, Colombia and Loreto, Ducke, Bautista + Araújo 3 Peru

36- Tryon et alli 3

Fig. 1 - Leaves of Scbizaea incurvata Schkuhr, two of the three fertile ones with conduplicate segments, growing at the Campina, km 60. Fig. 2 - Meiotic chromosomes of Schizaea incurvata n = ca. 154 showing various types o f bivalent associations, X 800. Fig. 3 - Dimorphic leaves in voucher collection of Trichoma­ nes arbuscula Desv., the fertile ones long petiolate. Fig. 4 - Late diplotene chromosomes of T. arbuscula n =ca. 128 showing various types of bivalent associations, X 600 .

Some of the extreme morphological and tinate Iam i na. Only a few plants were found ecological diversity among the species of in dense moss at the base of a large tree. Trichomanes is shown in the sample of spe­ Trichomanes e/egans has exceptionally large cies cytologically studied. A li of them grow leaves for the genus with the lamina finely in generally moist, shaded situations but occu­ dissected and more than 30 em long (Fig. 5). PY quite different habitats. Trichomanes ar­ We found only a single along a stream buscu/a forms dense colonies near the edge bank with the leaves overhanging the water. of tr.e water, along stream banks . The leaves Plants of T. pi/osum were abundant on the fa­ are dimorphic with the fertile ones long petio· ce of shaded sandstone rocks . The caespitose late (Fig. 3). Leaves of T. cristatum are mo­ leaves (Fig. 9) are covered with dense indu­ nomorphic, caespitose and with a deeply pec- ment. Trichomanes tanaicum is scandent and

Cl1romosome studies ... -37 quite a rare species although with a rather mewhat smaller but are in an earlier, diplote­ wide distribution in northern South America. ne stage prior to diakinesis. This species has We found only a single plant (Fig. 7) on an ca. 128 bivalents, the highest number known upright, dead tree trunk. for the genus which has also been reported The species of Trichomanes are excellent in T. crispum L. from Jamaica, by Walker cytological subjects for many have- relative:y (1966). He also has a record of n=64 in T. ar­ few, and remarkably large chromosomes as in buscu/a from Trinidad, which is considered as Fig. 6 of T. elegans and Fig. 8 of T. tanaicum. possibly 16 X. Thus our collection from Brazil The bivalents in T. arbuscula (Fig. 4) are so- with n= 128 may be 32X. The chromosome

1\

Fíg. 5 - Voucher collectíon of Trichomanes elegans Rích . with híghly divíded monomorphic leaves. Fig. 6 - Chromosomes of Trichomanes elegans at diakine~ís n=32, X 1000. Fig. 1 - Volicher collection of Trichomanes tanaicum Hook. with scandent rhizomes. The numerous elongate leaves with slender, marginal sori. Fíg. 8 - Chromo?omes of T. tanaicum at diakinesis n = 32, X lOOO.

38- Tryon et alii number of T. pilosum between n=62-68 (Fig. both T. elegans and T. tanaicum, which are 1O) is not clear beca use of severa! superimpo­ morphologically very distinct, indicates that sed bivalents, but certainly represents a rela­ number may be established in different evo­ tively high polyploid levei. lutionary I ines. Consideration of the chromo­ The species of Trichomanes are also good some numbers along with other aspects of cytological subjects because of the gradate the plants suggests that n=72 in T. cristatum sorus. Meiosis can usually be found on the (Fig. 11) may be constituted from a line based receptacle between the basal point where on 9 rather than 8 as in the other species. sporangia are initiated and the apex where Trichomanes elegans is a very distinctive they are dehiscing. Our record of n=32 in species and has been treated in subgenus

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...,. • f 12 , . .. ~~·~!..,_...... ~• • •.z •.. ,,., '• • 1_,\ S.. • • ,. '' •' , 111(.• ,.J •• • • " -~1-

Fig. n - Specimens of Trichomanes pilosum Raddi with caespitose leaves. Fig. 10 - Meiotic chromoso­ mes of Trichomanes pilosum with ssveral superimposed bivalents n=ca. 62-68, X 1000 . Fig. 11 - Chromo­ somes of Trichomanes cristatum Kaulf. at diakinesis n=72, X 1000. Fig. 12 - Chromosomes of Pityro· gramma calomelanos (L.) Link var. calomelaoos at diakinesis n = 116, X 800.

Chromosome studies ... -39 Pachychaetum, in its own section Davalliopsis, cussed in considerable detail by Walker (1966) in the treatment of the genera of the Hymeno­ and he postulates 6, 7, 8, and 9 as base num­ phyllaceae by Morton (1968). In that work, bers. In this system our records of 32, 64 and T. tanaicum and the other species that have 128 would be based on 8, while 72 would be been studied here are placed in different on 9. The scheme of Walker seems more plau­ sections of the subgenus Achomanes. sible than one proposed by Vessey & Barlow Chromosome numbers have been reported (1963) in which chromosomes are lost and in about 77 species of the different sets are combined to arrive at the and there is a considerable range of numbers correct sum. In that scheme n= 32 would be between 11 and 128. Derivation of the num­ based on X= 17 wHh the loss o f one and dou­ bers in the Hymenophyllaceae has been dis- bling to 32.

Pityrogramma Species, voucher Meiotic number General Distribution

P. calomelanos (L.) Link 116 Wide ranging from Mexico south to Bolí• var. calome/anos via and Argentina, Antilles and Floridêõ km 130, Bautista + Araújo 11

Plants are often abundant in open, sunny species is reported as n= ca. 120, from Jamai­ sites especially in disturbed places along ca , by Walker (1966). That same number is roadsides and on cleared hillsides. There were given for a specimen from northern lndia, and large colonies at km 130 where we collected there are also records of n=116 for plants ou r specimen at the edge ot the forest. Pity­ from southern lndia and Formosa. The species rogramma belongs to a complex of genera is regarded as wholly American, in the taxo­ that have chromosome numbers based on nomic treatment of the genus by R. Tryon X= 29, including Anogramma, Eriosorus, and ( 1962), but it i s noted that it h as been i ntro­ Jamesonia, although one of the most distincti­ duced in many are as of the paleotrop:cs. lt is ve species, Pityrogramma triangularis (Kaulf.) a frequent species in the American tropics. Maxon, in Ca lifornia ha,~ a diploid race with Further cytological work to determine whether n==30 and a tetrapolid race with n= 60. Seve­ both numbers do i ndeed occur in different po­ ra! nuclei in our preparations of Pityrogramma pulations and especially whether lower diploid ca/omelanos are clearly n= 116 as Fig, 12. The populations occur in the American trop·cs, will be of much interest.

Lindsaea Species, voucher Meiotic number General Distribution L. divaricata Kl. 42 Guatemala south to Bolívia and Paraguay Ducke, B~utfsta + Araújo 2 and also in Guadeloupe L. /ancea (L.) Bedd. 42 Panama south to Bolívia, Pará, and in Bahia var. fa/cata (Dryand.) Roserís. km 60, Bautista + Araújo 24 L. . quadrangularis Raddi 84-88 Southern Mexico south to Colombia, Cuba ssp. suba/ata Kraemer un~va l ents - km 130, Bautista + Araújo 18 L. schomburgkii Kl. ca. 84 Mostly Amazonian, also in Mato Grosso km 130, Bautista + Araújo 16 and Peru

40- Tryon et alli Lindsaea is a frequent genus in the moist chromosome numbers range between 34 and forests around Manaus and two or three spe­ 155. The most frequent, n= 47, is reported in cies may occupy the same si te. The plants nine species from widely distant areas as are terrestrial, commonly on stream ban!

Chromosome studies . .. -41 14

16

18

Fig. 13- Voucher collection of Lindsaea lancea (L.) Bedd. var. falcata (Dryand.) Rosenst. Fig. 14- Meio­ tic nuclei of "Lindsaea lancea var. falcata n = 42, X 1000 . Fig. 15 - Habit of Ieaves of Lindsaea divaricata Kl. growing at Reserva Florestal Ducke. Flg. 16 - Nucleus of Lindsaea divaricata at early diakinesis n = 42, X 1000. Fig. 17 - Meiotic nuclei of Lindsaea quadrangularis Raddii ssp. subalata Kramer with 84-88 lar· gely univalents and some bivalents, at arrow, X 1000 . Fig. 18 - Meiotic chromosomes of Lindsaea schom­ burgkii Kl. n=ca. 84, X 1000 .

42- Tryon et alii would represent an octoploid and our highest 77, 94, 96, 103, 270, 325 (± 30). 350-370, and number n= 128 would be 32X. Pityrogramma 540. A base number for Schizaea was propo­ ca/ome/anos with n = 116 represents an octo­ sed as X= 77. lf this is accepted, our speci­ ploid based on X= 29. The highest number mens would represent a relatively low levei among the species we report, n=ca. 154, in of ploidy, in spite of the high number of b:va­ Schizaea incurvata, is intermedtate in the se­ lents. ries of numbers reported for species of the The following table summarizes our re­ paleotropics and one of North America with ports on Amazonian fern cytology.

Number Figure Species Locality Maiotic Number

Schizaea incurvata Schkuhr INPA Station ca. 154 2 Trichomanes arbuscula Desv. km 130 ca. 128 4 T. cristatum Kaulf. km 60 72 11 T. elegans Rich. Ducke 32 6 T. pilosum Raddi km 130 ca. 62-68 10 T. tanaicum Hook. Ducke 32 8 Pityrogramma calomelanos (L.) Link var. calomelanos km 130 116 12 Lindsaea divaricata Kl. Ducke 42 16 L. lancea (L.) Bedd. var. falcata (Dryand.) Rosenst. km 60 42 14 L. quadrangularis Raddi ssp. 84-88 subalata Kramer km 130 univalents 17 L. schomburgkii Kl. km 130 ca. 84 18

ACKNOWLEDGEMENTS BROWNLIE, G. 1965 - Chromosome numbers in some Pacific pteridophyta. Pacific Sei., 19 (4 ) : We are grateful to Dr. Ghillean T. Prance, 493-497. KRAMER K. Director of the Curso de Botânica Tropical do 1 U. INPA for exp'Jditing our field and laboratory 1957 - A revision of the genus Linds11ea in the new world with not~s on a1lied genera. work. Dr. Osório Fonseca generously helped Act. Bot. NeerJandica, 6: 97-290. with some photographs of the chromosomes, MANTON, J. 1950 - Problems of cytology and evolution in and David Conant and Rolla Tryon assisted in the pteridophyta. Cambridge, England. herbarium and field work. MICKEL, J. T. 1966 - Chromosome observations on the fems of Mexico . Caryologia, 19 (1): 95-102 . RESUMO MORTON, C. V. 1968 - The genera, subgenera, and sections of São apresentados números de cromossomos, the Hymenophyllaceae. Contr. U. S. habitats e distribuição geral de 11 espécies (4 gêne­ Nat. Herb., 38 (5): 153-214. ros) de pteridófitas da região de Manaus. Estas NINAN, C. A. 1958 - Studies on the cytology and phylogeny são as primeiras contagens cromossômicas destas of the pteridophytes 6. Observalions espécies na América do Sul. São feitas compara­ on the Ophioglossaceae. 23 (3): 291-316. ções com números referidos para estes gêneros em TRYON, R. M. outras regiões geográficas. Os números variam en­ 1962 - Taxonornic fern notes 2. Pityogramma tre n = 32 e n = 154 e parecem representar altos ní• (including Trismaria.) and Anogramma. Contr. Gray Herb., 189: 52-76. veis de poliploidia. VESSEY, J. & BARIJOW, B. A. 1963 - Chromosome numbers and phylogeny LrTERATURE CITED in the Hymenophyllaceae. Proc. Linn. Soe. N. S. W., 88: 301-306. BRITrON, D. M. WALKER, T. G. 1974 - The signüicance of chromosome num­ 1966 - A cytotaxonomic survey of the pteri­ bers in fems. An, Mis. Bot. Gard., dophytes of Jamaica. Trans. Roy. Soe. 61 (2): 310-317. Edinburgh , 66 (9): 169-237.

Chrornosome studies ... -43