The Exclusively Neotropical Genus Scaphispatha Was Formerly Considered Monospecific. the Type Species

The Exclusively Neotropical Genus Scaphispatha Was Formerly Considered Monospecific. the Type Species

A REVISION OF SCAPHISPATHA (ARACEAE – CALADIEAE) INCLUDING A NEW SPECIES Eduardo Gomes Gonçalves1 ABSTRACT (A revision of Scaphispatha (Araceae – Caladieae) including a new species) The formerly considered monospecific genus Scaphispatha (Araceae – Caladieae) is here revised. Scaphispatha robusta E.G.Gonç, a second species for the genus is newly described from the Cerrado Biome and the transition Cerrado- Amazonia. It differs from S. gracilis Brongn. ex Schott by the much more robust petioles and leaves, primary lateral veins drying clearer than the lamina, lateral secondary veins conspicously more prominent than tertiary veins and for the female spadix with 11-15 rows of flowers visible in side view. A key to separate both species is provided, as well as ink illustrations and general remarks on the genus. Key-words: Scaphispatha, Cerrado, Caladieae, Araceae, geophyte. RESUMO (Revisão de Scaphispatha (Araceae – Caladieae), incluíndo a descrição de uma nova espécie para o gênero) O gênero Scaphispatha (Araceae – Caladieae), até então considerado monoespecífico, é aqui revisado. Scaphispatha robusta E.G.Gonç., uma segunda espécie para o gênero é descrita para o bioma Cerrado e a transição Cerrado-Amazonia. Difere de S. gracilis Brongn. ex Schott pelos pecíolos e folhas muito mais robustas, nervuras laterais mais claras que o limbo quando secas, nervuras laterais secundárias mais proemi- nentes que as terciárias e pela porção feminina do espádice com 11-15 espirais de flores visíveis em vista lateral. Uma chave para separar as espécies, assim como ilustrações em nanquim e aspectos gerais para o gênero são apresentados. Palavras-chave: Scaphispatha, Cerrado, Caladieae, Araceae, geófita. INTRODUCTION was recognized when plants from Pará state The exclusively neotropical genus (Northern Brazil) flowered in cultivation. Scaphispatha was formerly considered Sterile specimens of this species has been monospecific. The type species – Scaphispatha collected and seen for years, but they were gracilis – ranges from Brazil to Bolivia consistently considered as belonging to (Bogner 1980; Mayo et al. 1997), at the Caladium because of the large-sized peltate transitional areas between the leaves, usually speckled in white. phytogeographic provinces of the Cerrado, In order to make easier the comparisons Caatinga and the Amazonia. Despite the wide of the newly described species with the former occurrence, flowering seems to be an one, both are fully described and illustrated ephemeral event, so flowering specimens are and a taxonomic account for the genus is very rarely collected. Until living collections presented. were brought to cultivation by Josef Bogner in 1980, only three flowering collections TAXONOMICAL TREATMENT (including the type specimen) were History of the genus recognized in herbaria (Bogner 1980) and the The genus Scaphispatha was originally leaves were unknown. described by Heinrich Wilhelm Schott (1860), Recently, a second species of Scaphispatha Artigo recebido em 05/2005. Aceito para publicação em 08/2005. 1Universidade Católica de Brasília. Curso de Ciências Biológicas. Prédio São Gaspar Bertoni - sala M-206, QS-7, Lote 1 - EPTC. CEP 72030-170, Taguatinga - DF - Brazil. Phone: 55 61 356-9300 Financial support: Instituto Plantarum de Estudos da Flora Ltda; Biodiversidade do Bioma Cerrado (EMBRAPA, UnB, ISPN, DFID); Fundação Botânica Margaret Mee. 54 Gonçalves, E. G. based on a d´Orbigny specimen deposited Flowering and fruiting are said to occur in 10- the Herbarium of the Paris Museum. He used 14 days (Bogner 1980)! Inflorescences in the name suggested by Adolphe Brongniart Scaphispatha seem to appear in late October in the type sheet. It was placed in the tribe and infructescences are no longer to be found Caladieae, “Subtribus Problematicae”. In his by mid November. Leaves persist a little Das Pflanzenreich treatment, Engler placed longer, as long as late February. Scaphispatha in the subfamily Aroideae, tribe Zomicarpeae, together with Zomicarpa, Biogeography Ulearum, Zomicarpella and Xenophia (now Both species of Scaphispatha have more Alocasia). The reason for this placement was or less the same general occurrence, ranging the presence of a unilocular ovary with basal across the transition between the Cerrado anatropous ovules. biome and the Amazonia, with one species in The genus was reevaluated by Josef the transition between the Cerrado and the Bogner (1980) when new collections from Caatinga biome (dry thorn forest). Both Ceará State, Brazil, were brought into species can be considered sympatric to some cultivation. These new collections were taken extent, but the distributions present different very far from the original locality but a third patterns. Scaphispatha gracilis seems to collection was localized from Pará state. present a wider distribution, ranging from Bogner transferred Scaphispatha to the Ceará State to Bolivia, also penetrating deeply Englerian subfamily Colocasiodieae, subtribe in the Cerrado and reaching northern Goiás Caladiineae, based on chromosome numbers State. Scaphispatha robusta has a more or less and pollen type. This was also the first similar distribution, but it seems to penetrate description of its leaves, which has proven to more deeply in the Amazonia, probably be peltate. Mayo and collaborators (1997) occurring in deciduous forms of Amazonian summarized the current information of this forest, common in Brazilian States of Acre genus in their “The Genera of Araceae”, and Rondônia. providing detailed illustrations and including it in the tribe Caladieae, with no subtribal Relationships recognition. Since then, almost nothing has Scaphispatha belongs to the tribe been published about the genus, except a few Caladieae, together with the economically ecological remarks (Gonçalves 2004). important genera Xanthosoma, Caladium and Syngonium (Bogner 1980; Mayo et al., 1997). Ecology It is not supposed to be especially close to Both species of Scaphispatha are true any other genus in the tribe, but Scaphispatha geophytes, producing flowers and leaves was not surveyed in the only cpDNA during the rainy months and resting leafless phylogenetic analysis of the entire family, during the drier or colder months. Both species performed by French et al. (1995). occur in well drained soils, but S. gracilis Morphologically, Scaphispatha does not seems to prefer drier areas, occuring in open have any special aspect that would mark woodland (Cerradão), usually in shaded any obvious affinity on it. Vegetatively it portions near small ravines. Scaphispatha looks like a Caladium, with peltate leaves that robusta seems to prefer heavier soils, usually are sometimes white-speckled. The occurring in forest edges or nearby clearings inflorescence is also of a general type, and in the forest. the only remarkable aspect is the presence of Flowering is usually a short event and a unilocular ovary with basal ovules in the fruiting has proven to be even quicker. female flowers. Other interesting aspect that Rodriguésia 56 (88): 53-60. 2005 Revision of Scaphispatha 55 could be considered is the presence of a primary lateral veins forming a conspicuous short but noticeable style. Both features are collective vein, minor venation reticulate. shared with most genera of the small Inflorescences solitary, appearing much neotropical tribe Zomicarpeae. In fact, the before the leaves or together with them; tribe Zomicarpeae was considered inseparable peduncle from shorter to longer than the from Caladieae (French et al. 1995) and some petiole. Spathe usually decurrent at base, classifications have both groups in an constriction weak to moderate, tube expanded Caladieae (see Keating 2004). incompletely convolute. Spadix usually Anyhow, the inclusion of Scaphispatha shorter than the spathe, not constricted, in a phylogenetic analysis of the entire densely flowered, fertile male and female complex Caladieae-Zomicarpeae would help zones contiguous or separated by 1–3 rows the clarify which genus or genera are closest of sterile male flowers. Flowers unisexual, to Scaphispatha. A DNA phylogeny of the perigone absent. Male flower 4-6 androus, complex (as well as chromosome counts) has stamens connate in synandria, with a lateral been currently reconstructed by Gonçalves thecae opening by a slit or a “T” like opening; and collaborators and the results will be pollen grains solitary, inaperturate, exine published further. verrucose to subarolate. Female flower with a ovoid to obovoid ovary, 1-locular, ovules Scaphispatha Brongn. ex Schott, Prodr. Syst. 3–7, anatropous, basally attached by a short Aroid. 214 (1860). Type: S. gracilis Brongn. funicle; style well developed, connoid, much ex Schott. narrower than the ovary, stigma capitate, Tuberous herb, tuber globose or slightly slightly broader than the apex of the style. depressed apically. Leaf usually solitary, Infrutescence with persistent spathe tube, occasionally 2–3. Petiole long, marbled, berries subglobose, one seeded. Testa thin sheath short, inconspicuous. Blade always and smooth, endosperm abundant. peltate, ovate-sagittate to ovate-hastate, Chromosomes: 2n=28 (only counted for S. gracilis). Key to the species of Scaphispatha Petioles slender, rarely reaching 28 cm long (usually up to 20 cm long) and always less than 4 mm in diameter at base; primary lateral veins drying darker than the lamina; lateral secondary and tertiary veins not significantly different from each other; female part of spadix with 6-9 rows of flowers visible in side view. .................................................................................

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