Barry E. Hammel

Nyssa talamancana (Cornaceae), an addition to the remnant Laurasian Tertiary flora of southern Central America

A new species,Nyssa talamancana, with fruits larger than those of any other, either living or fossil, is described from Costa Rica and Panama. In size, number of germination valves, and surface-sculpturing, its endocarps resemble those of the fossil assemblage more than those of the other living species. The occurrence of this distinctive new member of a definitely Laurasian family, in association with other endemic or nearly endemic Laurasian taxa, at wet mid-elevations lends credence to the idea that these forests harbor remnants of the really ancient flora of southern Central America.

A noteworthy new species of Tovomita (Clusiaceae) from Amazonian white sand forests of Peru and Colombia

Tovomita calophyllophylla, from white sand forests of the Amazonian lowlands of Colombia and Peru, is described. The species is unique by its leaves and petioles which somewhat resemble those of two other genera of Clusiaceae,Calophyllum andGarcinia.ResumenTovomita calophyllophylla, una nueva especie de los bosques sobre arenas blancas de la Amazonía colombiana y peruana es descrita. Esta especie es única por sus hojas y peciolo que asemejan algo a los de otros dos géneros de Clusiaceae,Calophyllum y Garcinia.

Ruptiliocarpon (Lepidobotryaceae): A New Arborescent Genus and Tropical American Link to Africa, with a Reconsideration of the Family'

A new genus and species of trees from Costa Rica and northern South America, Ruptilio- carpon caracolito, is described and compared to the African Lepidobotrys. It is distinguished from Lepidobotrys primarily by its much shorter fila- ments, basifixed rather than versatile anthers, its lack of styles, its two-rather than three-locular ova- ry, and by its irregularly dehiscent fruits with a woody exocarp and cartilagineous endocarp. In wood anatomy, apart from the presence of vestured pits in Ruptiliocarpon, the two genera are remarkably similar. They match in important floral and fruit characteristics (dioecious; 5 + 5 stamens of unequal length with filaments fused at base; two apical, col- lateral ovules per locule; one-seeded fruit; black seed with a large red aril and no endosperm), and both have unifoliolate leaves with very fugaceous stipules and stipels, and leaf-opposed inflorescences. The familial placement of Lepidobotrys has been con- troversial: the genus was placed first in the Linaceae by Engler, then in the Oxalidaceae by Hallier, then in its own family (between Linaceae and Erythrox- ylaceae) by Leonard, and then again in the Oxali- daceae by Cronquist. Reviewing evidence, old and new, we maintain Ruptiliocarpon and Lepidobo- trys (only) in the Lepidobotryaceae and suggest that they relate more to Sapindales or possibly Euphor- biaceae than to Oxalidaceae.

Aspects of reproductive ecology of Clusia valerioi Standl. and Clusia peninsulae Hammel (sp. nov.), two Central American species of Clusiaceae with resin flowers

Clusia valerioi Standl. and C. peninsulae Hammel, sp. nov. (formally established in the Appendix), two Central American species of Clusiaceae offering resin as a floral reward, were studied in the Piedras Blancas National Park, SW Costa Rica. Basic data on phenology, flower structure, course of anthesis, flower visitors, flower visitation and pollination processes, fruit development and seed dispersal are communicated. Resin collection and pollen release are reported and documented in greater detail. The significance of stingless bees for pollination is confirmed, but honeybees were also observed to visit the flowers and to collect resin. The seeds of C. valerioi, exhibiting a clearly ornithochorous character syndrome, were observed to be eaten and dispersed by four species of the tanager family (Thraupidae) and one species of finch (Fringillidae). Ants were also observed to carry away the seeds.

Rubiacearum Americanarum Magna Hama Pars XXVIII: New Taxa, New Combinations, New Names, and Lectotypification for Several Species Found in Mexico and Central America

Abstract.  The Neotropical genus Borojoa Cuatrec. (Rubiaceae) is now considered a synonym of Alibertia A. Rich. ex DC. Consequently, three species named in Borojoa and found in Costa Rica and Panama are transferred to Alibertia with these corresponding nomenclatural changes: the new combination A. atlantica (Dwyer) Delprete & C. H. Perss. is based on B. atlantica Dwyer, the new name A. dwyeri Delprete & C. H. Perss. is provided for B. panamensis Dwyer, and the new combination A. patinoi (Cuatrec.) Delprete & C. H. Perss. is provided for B. patinoi Cuatrec. Additionally, the species A. premontana C. M. Taylor is reduced to a variety of A. edulis (Rich.) A. Rich. ex DC., as A. edulis var. premontana (C. M. Taylor) Delprete & C. H. Perss. A lectotype is selected for A. edulis. The recent publication of Arachnothryx chimalaparum Lorence ex Borhidi designated a holotype deposited at MO, but no such specimen has been located; a lectotype is here chosen based on a duplicate of the holotype deposited at MEXU. The new species Notopleura recondita Hammel & C. M. Taylor of the Osa Peninsula of Costa Rica can be distinguished from N. polyphlebia (Donn. Sm.) C. M. Taylor by its leaf blades with the secondary veins plane on the adaxial surface and its short cymose or paniculiform inflorescences. The new species Palicourea matamana C. M. Taylor of premontane forests of central-eastern Costa Rica can be separated from P. orosiana C. M. Taylor by its larger stipules, longer calyx lobes, and hirsute pubescence. The new species P. providenciana J. Sánchez-Gonz. & C. M. Taylor of montane forests in south-central Costa Rica can be separated from P. hammelii C. M. Taylor by its longer lanceolate stipule lobes, dark purple or yellow-flushed inflorescences, and shorter calyx lobes. The Panamanian plants treated previously as Psychotria acuminata subsp. boraginoides Dwyer are here considered to differ at the species level from P. acuminata Benth., and accordingly the new combination P. boraginoides (Dwyer) C. M. Taylor is here published for this species. Clarification of the identity of Cephaelis croatii Dwyer shows that it is a distinct species of Psychotria, and the new combination P. croatii (Dwyer) C. M. Taylor is published here for this species. The new species P. herrerana C. M. Taylor of central Costa Rica can be recognized by its combination of large, sessile, elliptic leaves, its large paniculiform inflorescences, and its relatively small corollas. Study of the Costa Rican plants previously called Rudgea thyrsiflora Donn. Sm. shows that these do not have the characters of Rudgea, but are similar to Psychotria racemosa Rich. and better included in this latter genus; the new name P. tsakiana C. M. Taylor is here published for this species. The new combination Simira panamensis (Dwyer) C. M. Taylor is published here based on the name Bathysa panamensis Dwyer, which has priority over the name S. darienensis Dwyer; both of the names Dwyer published are based on the same type specimen, thus the later name S. darienensis is illegitimate.

New species of Cyclanthaceae from southern Central America and northern South America

Four new species of Asplundia and one of Dicranopygium are described and illustrat- ed. Asplundia allenii is endemic to Panama, D. ta- tica is endemic to Costa Rica, A. brunneistigma is known from Costa Rica and Panama, A. ceci from Costa Rica to northern Colombia, and A. albicarpa from Costa Rica to Ecuador. Asplundia stenophylla, described originally from Costa Rica from sterile material and now known from Costa Rica to Ec- uador, is here provided with a full description in- cluding staminate and pistillate flowers, as well as fruits.

PRELIMINARY REPORT ON THE FLORA PROJECT OF LA SELVA FIELD STATION, COSTA RICA'

Finca La Selva is an intensively studied biological field station with a poorly known flora. Presently we can account for about 1,500 species of vascular plants but the flora may contain as many as 2,000. Although collecting has been nearly continuous since the beginning of the project in the summer of 1979, we are still finding novelties. Experience at La Selva has driven home the fact that certain genera of both bulky and inaccessible plants have been habitually ignored by botanical collectors in the tropics. The wet Caribbean lowlands of Central America have themselves been relatively inaccessible and ignored. General collecting throughout the region is urgently needed. HISTORY Finca La Selva is a 730 hectare4 biological field station owned and operated by the Organization for Tropical Studies (OTS), which is a consortium of North and Central American universities. The station is located near the confluence of the Puerto Viejo and Sarapiqui rivers in the province of Heredia in the Caribbean lowlands of northeastern Costa Rica. The property encompasses about 650 hectares of primary forest in addition to 80 hectares of disturbed land, including old pasture, abandoned cacao and pejibaye (peach palm) plantations, 25-year-old successional woods, and regularly maintained one- through five-year-old successional plots. In the Holdridge Life Zone system, the vegetation is classified as Tropical Premontane Wet Forest (Holdridge et al., 1971). The average annual rainfall is about 3,900 mm. The elevation varies from 100 m along the Rio Puerto Viejo on the north edge of the property to 220 m in the ridge-dissected southern section (Petriceks, 1956). Thus, the altitudinal range from one end of the property to the other, a distance of about 3.4 km, exceeds that from the Caribbean coast to the La Selva field station, a distance of about 55 km. For the last 12 years the station has been the annual site of as many as three OTS courses in tropical ecology as well as a number of courses offered by other institutions. The site has served almost continuously for the last 25 years as base for many researchers and has been particularly attractive to plant ecologists. A bibliography of published papers based on work done at La Selva contained about 200 entries by fall of 1981. Nevertheless, until recently fewer than half the species of vascular plants now known to occur at the station had been even tentatively identified or otherwise accounted for. The need for a means to identify plants at La Selva has been ever-present. Standleys Flora of Costa Rica (1937-1938) is much out of date and provides only

Lectotypification and Reinstatement of Stachytarpheta friedrichsthalii (Verbenaceae), with Notes on the Lectotypification of S. indica

Abstract.  Certain material of Stachytarpheta Vahl (Verbenaceae), mostly from the Caribbean coast of Central America (from Honduras to Panama), apparently related to S. calderonii Moldenke and S. indica (L.) Vahl, but consistently misidentified as S. jamaicensis (L.) Vahl, has been identified as S. friedrichsthalii Hayek. Examination of both syntypes of the latter name (Fendler 219, MO; Friedrichsthal 466, W) confirms that the calyx is more or less bilobed, versus 4-toothed in S. jamaicensis, under which S. friedrichsthalii has erroneously been placed in synonymy. One of the two sheets of Friedrichsthal 466 (W)—the one corresponding to Field Museum negative 34320—is chosen as the lectotype. Contrary to recent suggestion, the latest lectotypification of Verbena indica L. (on a portion of LINN 35.1) is found to be consistent with its protologue, and the consequent synonymy of S. angustifolia (Mill.) Vahl under S. indica is here accepted. Furthermore, it is suggested that S. friedrichsthalii may also be the correct name for some African material that has been included in S. indica (in much the same way S. friedrichsthalii has been found among Central American material of S. jamaicensis).

The origami of botany: a guide to collecting and mounting specimens of Cyclanthaceae

Guidelines for preparing and mounting specimens of Cyclanthaceae, as well as a key to the genera, are presented in order to facilitate collecting of a difficult and often neglected family. In general, specimens should be prepared so the depth of the leaf division is apparent and the lower surface of the basal part of the leaf is visible or accessible. The family Cyclanthaceae has far fewer species than the other related families of large intractable monocots for which guides to the preparation of herbarium specimens have recently been published (Croat, 1985; Dransfield, 1986; Stone, 1983). Nevertheless, in much of the wet lowlands of the Neotropics the cyclanths form a very conspicuous element of the understory and epiphyte flora (Figs. 1, 2). Careful collecting in almost any area of wet primary forest often yields new species because the family is poorly represented in herbaria and many species are narrowly endemic. This paper is a call for more collections as well as a guide to help insure that they be properly prepared.

Clusia hirsuta, a New Species from Clusia sect. Retinostemon and the First Description of Trichomes in the Genus

Abstract. Clusia hirsuta Hammel (Clusiaceae), a new species from the Pacific wet forest in Colombia and Ecuador, is described. Trichomes are reported here for the first time in the genus and described using micromorphological techniques. Morphological and molecular data are used to establish the phylogenetic position of this newly described taxon within the genus Clusia L.