A revision of the genus <Emphasis Type="Italic">Podococcus</Emphasis> (<Emphasis Type="Italic">Arecaceae</Emphasis>)

Summary  A taxonomic revision of the palm genus Podococcus (Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed     

A revision of asterogyne (Arecaceae: Arecoideae: Geonomeae)

A taxonomic revision of the neotropical genusAsterogyne Hook. (Arecaceae: Arecoideae: Geonomeae) is presented. The genus is characterized by one autoapomorphic character, the separation of anther thecae by a bifid connective, and the combination of small to medium-sized stems, bifid simple leaf blades, floral pits in bud covered by a rounded upper lip that overlaps a lower lip, and pistillate flowers with staminodial lobes that are displayed in a starlike shape. Five species are recognized in this treatment: one of them (Asterogyne martiana) is widely distributed from Belize in Central America to northern Ecuador, three species (A. ramosa, A. spicata, andA. yaracuyense) are endemic to small areas in the Venezuelan Coastal Range, and one species (A. guianensis) is endemic to eastern French Guiana. The taxonomic history, morphology, reproductive biology, distribution and ecology, intrageneric relationships, and conservation status are reviewed.     

A revision of the Greater Antillean species of Bactris (Bactridinae: Arecaceae)

Three species ofBactris are recognized in the Greater Antilles:B. cubensis (from Cuba),B. plumeriana (from Hispaniola), andB. jamaicana (from Jamaica). A cladistic analysis of the non-ocreate clade—i.e.,Bactris cubensis, B. plumeriana, B. jamaicana, B. macana, andB. gasipaes—confirmed that the Greater Antillean species ofBactris form a monophyletic group, i.e., the Antillean clade. Synapomorphies supporting the Antillean clade are mesocarp and endocarp fibers numerous, parallel, predominantly narrow, few broad, extending the entire length of the endocarp; and leaf segments 45–80 per side of rachis. The presence of fiber-sclereids in the leaf lamina, and petals of the staminate flowers ovate to ovatetrullate, with sparsely branched fibers, may represent additional synapomorphies.Bactris plumeriana andB. jamaicana are hypothesized to be sister species, a grouping weakly supported by their short anthers. Each species has at least one autapomorphy; therefore, all are considered to be a cladospecies. Noteworthy interpopulational variation occurs withinBactris plumeriana andB. cubensis.     

Flowering biology ofGeonoma irena andG. cuneata var.sodiroi (Arecaceae)

The phenology and flowering of two sympatric understory palms from western Ecuador, until recently regarded as conspecific, is described.Geonoma irena Borchs. flowers throughout the year. Anthesis lasts 11–14 weeks per inflorescence, with overlapping male and female phases. Flowers open in the midmorning, and are visited mainly by meliponid and halictid bees.Geonoma cuneata var.sodiroi (Burret)Skov flowers from December to April, with a distinct peak in Feburary. Anthesis lasts 6–8 days per inflorescence, with non-overlapping male and female phases. Flowers open at dawn, and are visited mainly by drosophilid and sphaerocerid flies. The flowering pattern of the two species match different specific behavioural features of their insect visitors. The study provides an example of how differences in reproductive biology may act as an important barrier to gene flow between related, co-occurring taxa.     

Pathways of karyological differentiation in palms (Arecaceae)

Karyological data are given for 56 palm taxa coming from all 6 palm subfamilies. In 11 genera and 17 species, chromosome numbers are reported for the first time. Most chromosome numbers in palms range between 2n = 36 and 2n = 26 in dysploid series. Species of the same genus usually exhibit identical chromosome numbers which additionally may be constant in larger groups of closely related genera (Coryphoideae trib.Corypheae with nearly always 2n = 36,Arecoideae subtribesEuterpeinae andRoystoneinae with 2n = 36,Arecoideae subtrib.Butiinae with mostly 2n = 32). Polyploidy among palms is of minor significance but the endemic Madagascan genusVoanioala (2n = 606 ± 3) is the most striking exception. — With respect to structure of interphase nuclei and longitudinal differentiation of prophase and metaphase chromosomes, the palm family is highly differentiated. Euchromatin types with different prophase condensation properties and fluorochrome and C-banding patterns of heterochromatin permit a discrimination of several subfamilies on the nuclear level (Arecoideae, Ceroxyloideae, Nypoideae, Phytelephantoideae, Calamoideae).Arecoideae andCeroxyloideae, andNypoideae andPhytelephantoideae have some features in common. Subfam.Coryphoideae s. l. is a non-uniform group. — Nuclear characters among palms exclusively found in recentCoryphoideae subtrib.Thrinacinae link palms with other monocotyledons. Most probably, such a nuclear condition represents an ancestral state in the evolution of palm genomes within subfam.Coryphoideae s. l., but also the conspicuous nuclear characters of the other modern palm subfamilies appear to be derived from a similar starting point, since transitional character states are still present in subfam.Calamoideae and some taxa of subfam.Arecoideae. Early karyoevolution in palms obviously did not involve numerical change of the ancient chromosome number of 2n = 36 which started subsequently, as a dysploid reduction in numerous parallel series, independent in subfam.Coryphoideae (2n = 36 to 2n = 28),Calamoideae (2n = 36 to 2n = 26),Ceroxyloideae (2n = 34 to 2n = 26), andArecoideae (2n = 36 to 2n = 28). Possible mechanisms of karyological change are discussed. — Karyological characters are compared to morphological, ecological, taxonomical, and chorological features, and give some new insight into older and more recent phases of palm evolution. (1) Strong deviations in vegetative or floral morphology are often accompanied by major karyological differences, and sometimes the direction of advancement can be traced through intermediate stages. (2) Apart fromCoryphoideae subtrib.Thrinacinae, the strongest concentration of apparently original karyological traits is found in the more basal members of each subfamily. (3) The most successful and actively radiating colonizers of the forest floors in evergreen tropical forests which belong to completely different subfamilies (Old WorldLicuala, New WorldChamaedorea andGeonoma), appear to be very advanced karyologically.     

Floral scent chemistry and pollination ecology in phytelephantoid palms (Arecaceae)

The subfamilyPhytelephantoideae comprises three genera (Ammandra, Aphandra, andPhytelephas) and seven species of dioecious palms. The floral scents ofAmmandra dasyneura, A. decasperma, Aphandra natalia, Phytelephas aequatorialis, P. macrocarpa, andP. seemannii were analyzed by gas chromatography-mass spectrometry. We studied the pollination biology ofA. natalia, P. aequatorialis, andP. macrocarpa, and tested how the synthetically produced main constituents of the floral scents ofAphandra andPhytelephas attracted insects in two natural populations ofPhytelephas. The genera are distinct in terms of floral scents.Ammandra has sesquiterpenes,Aphandra (+)-2-methoxy-3-sec-butylpyrazine, andPhytelephas p-methyl anisol. These constituents dominated the scents quantitatively and qualitatively. The similarity between scents of male and female inflorescences was 76.5% inAmmandra, 84.2% inAphandra, and >99% inPhytelephas. Different species ofAleocharinae (Staphylinidae) pollinateAphandra natalia andPhytelephas species and reproduce in their male inflorescences.Derelomini (Curculinoidae) andMystrops (Nitidulidae) only visit and pollinatePhytelephas in which male inflorescences they reproduce. A species ofBaridinae (Curculionidae) only visits and pollinatesAphandra natalia, and reproduces in its female inflorescence. The apparent reliance on one or a few floral scent constituents as attractants and few and specific pollinators may indicate co-evolution. Sympatric species ofPhytelephantoideae have different scents. We suggest that species with similar scents have allopatric distributions due to the absence of a pollinator isolation mechanism.     

A revision of the <Emphasis Type="Italic">Heterospathe elegans</Emphasis> (<Emphasis Type="Italic">Arecaceae</Emphasis>) complex in New Guinea

Summary  Three closely affiliated species of Heterospathe Scheff. (H. elegans (Becc.) Becc., H. humilis Becc. and H. versteegiana Becc.) from New Guinea are revised. They are reduced to a single species which is divided into two subspecies, and the new combination H. elegans subsp. humilis (Becc.) M. S. Trudgen & W. J. Baker is made. The subspecies can be readily distinguished by their growth habit. Epitypes are designated for the three previously published names, as informative material on the habit is not included in the existing type specimens. A new, potentially related species is described as H. pullenii M. S. Trudgen & W. J. Baker.     

A phylogenetic analysis of the palm subtribe Oncospermatinae (Arecaceae) based on morphological characters

Subtribe Oncospermatinae (Arecaceae: Arecoideae: Areceae) is a diverse group of spiny Old World palms. The subtribe includesOncosperma, a widespread Asian genus of five species, along with seven monotypic genera, all endemic to the Seychelles and Mascarene Islands of the western Indian Ocean. A phylogenetic analysis was conducted in order to test the monophyly of subtribe Oncospermatinae with respect to other Old World genera of tribe Areceae. A matrix of 38 morphological characters was scored for 29 taxa, including 11 species of the Oncospermatinae. A single most parsimonious tree was found, resolving the subtribe as a polyphyletic group of two distinct clades. One clade containingAcanthophoenix, Deckenia, Oncosperma, andTectiphiala was placed as sister to a large group that includes members of subtribes Archontophoenicinae, Arecinae, Iguanurinae, and Ptychospermatinae. The other clade of Oncospermatinae, including the Seychelles endemic generaNephrosperma, Phoenicophorium, Roscheria, andVerschaffeltia, was resolved as sister to the Madagascar endemic subtribe Masoalinae, and may have arisen in the western Indian Ocean region.     

Calospatha subsumed in Calamus (Arecaceae: Calamoideae)

Summary  Based on previously published phylogenetic research, the genus Calospatha Becc. (Calamoideae) is placed in synonymy within Calamus L. The new combination, Calamus calospathus (Ridl.) W. J. Baker & J. Dransf. is made.     

A synopsis of the genus allomarkgrafia (Apocynaceae)

The nine species of the genusAllomarkgrafia are treated synoptically, with a review of their systematics and nomenclature. Two new species,Allomarkgrafia ecuatoriana andA. insignis, and a new combination,Allomarkgrafia campanulata, are proposed here.     

A revision of the genus Hemitrochostoma (Hemiptera,Heteroptera, Plataspidae)

The genus Hemitrochostoma Bergroth, 1913 (Hemiptera, Heteroptera, Plataspidae) is redescribed and reviewed. Two species are recognized: the type species Hemitrochostoma altilabris Bergroth, 1913 (Malaysia: Sarawak), and Hemitrochostoma rutabulum sp. n. (Malaysia: Perak). The following new subjective synonymies are proposed: Hemitrochostoma Bergroth, 1913 = Inflatilabrum Tomokuni, 2012, syn. n.; Hemitrochostoma altilabris Bergroth, 1913 = Inflatilabrum lambirense Tomokuni, 2012, syn. n.     

A revision of Casimirella,including Humirianthera (Icacinaceae)

Casimirella Hassler (1913) is accepted and Humirianthera Huber (1914) considered a synonym. Casimirella diversifolia and C. lanata from Brazil are described as new species. Casimirella ampla (Miers) based on Leretia ampla Miers, C. crispula (Howard) based on Humirianthera crispula Howard, and C. rupestris (Ducke) based on Humirianthera rupestris Ducke are new combinations.     

Taxonomic revision of the genus Prionopelta (Hymenoptera,Formicidae) in the Malagasy region

In this study we revise the taxonomy of the genus Prionopelta for the Malagasy region, treating seven species, six of which are newly described (Prionopelta laurae sp. n., Prionopelta seychelles sp. n., Prionopelta subtilis sp. n., Prionopelta talos sp. n., Prionopelta vampira sp. n., Prionopelta xerosilva sp. n.), and one redescribed (Prionopelta descarpentriesi Santschi). One species, Prionopelta seychelles, is restricted to Seychelles, while the six remaining species treated are endemic to Madagascar.     

A revision of epidendrum subgenus epidanthus (Orchidaceae)

Epidendrum subgenusEpidanthus (L. O. Williams) Barringer (Orchidaceae) is a group of small, slender-stemmed epiphytes formerly classified in the genusEpidanthus L. O. Williams. The seven species are distributed from southern Mexico to Columbia in wet forests, usually above 1000 m in elevation. Species of subgenusEpidanthus are distinguished from the rest ofEpidendrum by their linear leaves, slender stems, and two pollinia. The new speciesEpidendrum aurigineum is described and the new nameEpidendrum, insolatum is created forE. crassum (Dressler) Mora-Retana & J. García.     

A synoptic revision of Dacryodes (Burseraceae) in Africa, with a new species from Central Africa

Summary  A synoptic revision is presented for the genus Dacryodes Vahl in Africa. The studies are based on examination of herbarium material. Eighteen species are recognised, including two not well known due to poor material. The new species Dacryodes villiersiana Onana is described and illustrated. The conservation status of the species is discussed following the categories and criteria of IUCN (2001).     

Flowering, pollination, nectar standing crop, and nectaries ofEuterpe precatoria (Arecaceae), an Amazonian rain forest palm

Flowering and pollination biology of the monoecious palmEuterpe precatoria was studied in the forest of the Reserva Ducke near Manaus, Brazil, during two annual flowering periods (middle of October to end of March) between 1991 and 1993. Individuals produced one to four bisexual inflorescences per flowering period. Inflorescences have staminate and pistillate flowers in triads. The anthesis of the whole inflorescence averaged 26 days, with the male phase extending over the first 17 days, followed by six days without any open flowers, and the female phase covering the last three days. The distinct dichogamy of the inflorescence results in obligate outcrossing. The pollen-ovule ratio is high (42000). Both male and female flowers emit an almond oil-like scent and produce nectar in septal nectaries. The concentration and total amount of sugar of the nectar of female flowers (37% and 0.021 mg) were significantly higher than that of male flowers (9% and 0.007 mg). The nectar is hexose-rich and with a moderately high amino acid concentration (68 µg/ml).Euterpe precatoria seems to be a generally entomophilous palm with a predominance of beetles and bees as potential pollinators. The most constant visitors were beetles of the familiesCurculionidae, Chrysomelidae, Staphylinidae, and bees of the familyHalictidae. The actual composition of the insect spectrum depends on climatic and biotic factors. Additionally, wind pollination may occur. Fruit development lasted four months and ripe fruits are swallowed by toucans who thus disperse the seeds.This study is part of an unpublished doctoral thesis of the first author. The paper is dedicated to emer. Univ.-Prof. DrFriedrich Ehrendorfer at the occasion of his 70th birthday