James D. Skean

Multiple Events of Dispersal and Radiation of the Tribe Miconieae (Melastomataceae) in the Caribbean

In the Caribbean region, the Melastomataceae are represented by about 450 species (from 28 genera), close to 400 of them endemic. The majority of these endemic species (approximately 330) belong to the tribe Miconieae, a monophyletic group characterized by flowers with inferior or partly inferior ovaries that develop into baccate fruits, stamens with no or only poorly developed connective appendages, and the absence of megastyloids and imbricate bracts at the base of the flowers. A phylogenetic analysis of 460 accessions from 450 species of the tribe Miconieae, including 139 present in the Antilles (103 of these endemic), was performed based on nuclear (nrITS) and plastid (ndhF) DNA sequence data. This analysis shows that most of the Caribbean endemics are the product of five radiation events: (1) a clade containing the Caribbean endemic (or near-endemic) genera Pachyanthus, Calycogonium, Tetrazygia and Charianthus, as well as a few representatives of Miconia and Leandra. (2) The genus Mecranium. (3) The Caribbean species of Miconia section Chaenopleura (which are probably not the sister group of Andean Chaenopleura). (4) The Greater Antillean species of Clidemia and Ossaea (including Sagraea). (5) The Lesser Antillean representatives of Clidemia. Caribbean endemics that are more closely related to mainland species, rather than other Caribbean species are rare, and these often are segregates of widespread continental species. Because of a lack of resolution at the base of several clades, it is currently not possible to determine which mainland groups are the closest relatives of these Caribbean endemics, thus preventing us from establishing unequivocally the geographical origins of these species.ResumenEn la región del Caribe la familia Melastomataceae está representada por cerca de 450 especies (de 28°géneros), 400 de ellas endémicas. La mayoría de estas especies (approximately 330) pertenecen a la tribu Miconieae, un grupo monofilético caracterizado por flores con ovario parcial o totalmente ínfero que se desarrollan en frutos bayados, estambres con apéndices ausentes o poco desarrollados, ausencia de mega estiloides, y la ausencia de brácteas imbricadas en la base del as flores. Se realizó un análisis filogenético basado en secuencias nucleares (nrITS) de cloroplasto (ndhF) para la tribu Miconieae. El análisis incluyó 460 individuos, representando 450 especies de la tribu, de las cuales 139 están presentes en el Caribe (103 de estas endémicas). El análisis muestra que la mayoría de las especies endémicas del Caribe son producto de cinco eventos de radiación: (1) Un clado que contiene los géneros endémicos (o casi endémicos) Pachyanthus, Calycogonium, Tetrazygia y Charianthus, así como representantes de Miconia y Leandra. (2) El género Mecranium. (3) las especies Antillanas de Miconia sección Chaenopleura. (4) Las especies de las Antillas mayores de Clidemia y Ossaea (incluyendo Sagraea). (5) Las especies de las Antillas menores de Clidemia. Especies endémicas del Caribe que son hermanas o que están cercanamente relacionadas con especies del continente, y no con especies de la región son raras, y generalmente son segregadas de especies de amplia distribución. Debido a la falta de resolución en la base de muchos de estos clados en este estudio, en este momento no es posible determinar con precisión que grupos presentes en el continente son hermanos a los grupos del Caribe, por lo que no es posible establecer los orígenes geográficos de la mayoría de grupos endémicos.

A New Dicerandra (Labiatae) from the Lake Wales Ridge of Florida, with a Cladistic Analysis and Discussion of Endemism

Dicerandra christmanii, differing from D. frutescens in anther and corolla color, essential oils, average leaf length, and anther connective glandularity, is described from sclero- phyllous oak-sand pine scrub on yellow, well drained sandy soils near Sebring, in Highlands County, Florida. Its distinctness and phylogenetic placement are substantiated by phenetic analysis of mor- phological features, field study of variability in natural populations, survey of leaf essential oils, SEM study of anther micromorphology, preliminary investigation of pollination biology, garden observations, and a revised cladistic analysis of the genus. The discovery of D. christmanii is indicative of the need for additional taxonomic studies involving the highly endemic flora of the Lake Wales Ridge, a region of extensive and continuing habitat destruction due to agricultural and urban development.

Two new species of Miconia sect. Sagraea (Melastomataceae) from the Macaya Biosphere Reserve, Haiti, and twelve relevant new species combinations

The Sagraea clade (Melastomataceae, tribe Miconieae) is briefly characterized, typified, and formally treated as a section within Miconia. In addition, two new species of Miconia sect. Sagraea, endemic to the floristically diverse Massif de la Hotte of southwestern Haiti and discovered during the course of a systematic revision of the Caribbean species of this section, are here described and illustrated. Miconia hottensis and M. navifolia, morphologically similar and possible sister species, are compared to each other and to the widespread Caribbean species M. capillaris and the southwestern Dominican Republic endemic M. tetraptera; these four species share rectangular stems with four low ridges or wings and minute, short-stalked, peltate or pseudopeltate hairs and likely form a clade.

Taxonomic studies in the Miconieae (Melastomataceae). VI: Miconia santanana, a new species from Hispaniola

Miconia santanana, which occurs in broad-leaved forests along streams of pineland habitats in the Cordillera Central of the Dominican Republic, is described and illustrated. It is compared withM. ferruginea andM. adenocalyx, two presumed close relatives withinMiconia sect.Chaenopleura. Eco-geographic characterizations and a key are presented for these three species.

A new species of Henriettea (Melastomataceae) from the Sierra de Baoruco, the Dominican Republic

Henriettea uniflora, which is known only from a diverse moist montane forest in the vicinity of Loma Trocha de Pey (or “Monteada Nueva”), Loma Pie de Palo, and Loma Remigio, the easternmost peaks of the Sierra de Baoruco, is described and illustrated. It is compared to species of the Henriettea squamulosa complex, especially H. squamulosa and H. ciliata. The species of this complex are characterized by an indumentum of ferruginous, stellate-lepidote hairs.

Taxonomic studies in the Miconieae (Melastomataceae). IX. Calycogonium formonense, a new species from the Massif de la Hotte, Haiti

Calycogonium formonense, a new species, is here described from the floristically diverse Massif de la Hotte of southern Haiti. It is compared to C. hispidulum, to which it is likely related. Although the genus Calycogonium is not monophyletic, C. formonense and C. hispidulum are probably related to other species, e.g., C. calycopteris, C. heterophyllum, and C. reticulatum, that exhibit reduced inflorescences and 4-merous flowers having hypanthia with four conspicuous lobes separated by longitudinal grooves and external calyx lobes that are flattened parallel to the floral radii. These distinctive species may form a clade. Calycogonium formonense is distinguished from C. hispidulum by its smaller leaves with the tertiary veins not raised on the abaxial surface, with entire margins (i.e., margin without elongate multicellular hairs), and usually solitary flowers.

Taxonomic studies in the Miconieae (Melastomataceae). VII. Miconia howardiana, a new speices from Hispaniola

Miconia howardiana, which is known only from a diverse moist montane forest in the vicinity of Loma Trocha de Pey (or “Monteada Nueva”), the easternmost peak of the Sierra de Baoruco, is described and illustrated. It is compared to phenetically similar (and probably phylogenetically related) species of theMiconia favosa complex, i.e.,M. favosa, M. xenotricha, M. campanensis M. Sintenisii, M. foveolata, andM. pycnoneura. The species of this complex are characterized by bullate leaves with frequently cordate bases and often six secondary veins. Most species also have large berries and flowers, 5-locular ovaries, large inflorescence bracts and bracteoles, and more or less dendritic multicellular hairs.

Two New Species of Meriania (Melastomataceae) from Hispaniola

Two new species, Meriania brevipedunculata and M. parvifolia, are described from Morne Formon in Parc National Pic Macaya, in the Massif de la Hotte, Haiti. These species are compared with M. involucrata, M. ekmanii, and M. squamulosa, the three species of the genus previously known from Hispaniola. All five species are endemic to Hispaniola, and all except M. involucrata are limited to the Massif de la Hotte, a region of exceptional endemism. The flora of the Massif de la Hotte is discussed briefly. In the course of field work in connection with a biogeophysical inventory of the recently es- tablished Parc National Pic Macaya in the Mas- sif de la Hotte, Haiti, the following two unde- scribed species of Meriania Sw. (Merianieae) were collected. They are described below and compared with related taxa. Both species are recorded only from the Morne Formon region, the flora of which is known mainly through the work of Erik L. Ekman (see Ekman 1928 and unpublished field notes at Stockholm; Moscoso 1943).

Rediscovery of Ossaea alloeotricha, an endemic of the high-elevation Massif de la Hotte, Haiti, and its transfer to Miconia (Melastomataceae: Miconieae)

Ossaea alloeotricha, described by Urban on the basis of material with very immature flowers, has been re-collected (in flower and fruit) in the cloud forests and moist forests dominated byPinus occidentalis in the vicinity of Pic le Ciel, 2150 m, on Morne Formon of the Massif de la Hotte (western group), Haiti. The mature flowers of this species have broadly elliptic to suborbicular petals with rounded, asymmetrically notched apices, clearly indicating a placement inMiconia, notOssaea orLeandra (which have acute to acuminate petals); the species is here transferred toMiconia (sect.Cremanium).Miconia alloeotricha is provided with an expanded description and compared withM. desportesii, M. monciona, M. sphagnicola, andM. tetrandra, the other species ofMiconia sect.Cremanium occurring in Hispaniola (Dominican Republic and Haiti), and with the phenetically similarM. acuminata (sect.Chaenopleura), with which it occurs in the moist forests near and at the peak of Morne Formon. With the transfer ofOssaea alloeotricha toMiconia, we estimate that 58 species ofMiconia occur onHispaniola.