Lowland Coastal Forests Research Articles

SEDIMENTARY FACIES AND DEPOSITIONAL ENVIRONMENTS OF DIVERSE EARLY PALEOCENE FLORAS, NORTH-CENTRAL SAN JORGE BASIN, PATAGONIA, ARGENTINA

We here investigate the sedimentology of the early Danian (ca. 66–64 Ma) Salamanca Formation in the north-central San Jorge Basin, southern Chubut Province, Patagonia, Argentina, in order to place the outstandingly diverse and well-preserved fossil floras it contains into specific environmental settings. These assemblages are among very few of Danian age from the entire Southern Hemisphere and thus provide critical data about geographic variation in recovery from the end-Cretaceous extinction. Understanding the depositional context of the Salamanca floras is necessary for comparison with other assemblages and for interpreting their exceptional preservation. The Salamanca Formation was deposited above a widespread erosional sequence boundary (SB-1) resulting from a relative base level rise and widespread marine transgression during the early Danian (Chron C29n). In response to this increase in accommodation space, a broad, shallow estuary formed that most likely extended westward at least as far as the San Bernardo belt. A transgressive systems tract was deposited in this estuary, consisting of bioturbated sand fining upwards to silt. The maximum marine flooding surface at the beginning of the highstand systems tract is defined by well laminated, unburrowed, clay deposits of a low energy, deep shelf. The Salamanca highstand systems tract (HST) consists of sandy and silty facies capped by accreting subtidal bars and sandy shoals containing an abundance of tidal indicators, suggesting deposition proximal to the San Jorge paleo-estuary head. A second sequence boundary (SB-2), formed during Chron C28r and early C28n, separates the older highstand deposits from younger lowstand and transgressive deposits. These consist of estuarine sand shoals, trough cross-bedded sands deposited in aggrading, fluvially influenced tidal channels, tidal flat muds, and bayhead deltas. The best preservation of compression floras and petrified trees occurred near the tops of subtidal bars below SB-2; at the end of the shallowing-upward cycle that caps the second HST; and in fluvially-influenced tidal channels, tidal flat mudstones, and bayhead deltas of the lowstand and transgressive systems tracts that lie above SB-2. These settings were proximal to the source forests and had rapid rates of burial. We interpret the dark muds of the Banco Negro Inferior, which cap the Salamanca Formation, as a late transgressive and highstand systems tract deposited during a time of rising groundwater table and declining river slopes in a widespread, lowland coastal forest.

Guatteria darienensis (Annonaceae), a new species from Panama and Colombia

Guatteria Ruiz & Pavón (1794: 85) is the largest genus of Annonaceae with about 210 recognized species (Chatrou et al. 2012, Maas et al. 2011). It comprises small- to medium- sized trees, rarely canopy trees or shrubs, and only two species are lianas, Guatteria scandens Ducke (1925:10) and G. fractiflexa Maas & Westra (2008: 491; Erkens et al. 2008). It is widely distributed throughout Mesoamerica, the Caribbean, and tropical South America (Erkens & Maas 2008). Species of Guatteria are common members of Neotropical forests where they occupy a wide variety of habitats, such as lowland rain forests, gallery forests, semideciduous forests, coastal forests, inundated forests, savannas and montane forests (Erkens et al. 2007b). However, the highest species diversity is found in the Amazon Basin with approximately half of the species occurring there. Central America harbours ca. 30 species, mostly endemics (Erkens et al. 2008) of which ca. 20 species occur in Panama, a highly under-collected country with respect to Guatteria (Erkens et al. 2006). In the adjacent Colombian Chocó region, we found ca. ten endemic species, and to date, only two species, Guatteria aberrans Erkens & Maas (2006: 201) and the new species described in this paper, are restricted to Panama and northwestern Colombia.

A new species of triadal coral snake of the genus Micrurus Wagler, 1824 (Serpentes: Elapidae) from northeastern Brazil.

The genus Micrurus comprises 123 currently recognized taxa (species and subspecies) that are traditionally arranged in four species groups diagnosable mainly by color pattern characteristics. Here, we describe a new species of triadal coral snake from northeastern Brazil. The new species is distinguished from other sympatric triadal congeners (M. lemniscatus carvalhoi, M. ibiboboca and M. brasiliensis) mainly by the entirely black parietals and by a suite of external characters and hemipenial morphology. The new species appears to be restricted to tropical ombrophilous lowland coastal forests of northeastern Brazil and all recently collected specimens are known to occur in small forest patches surrounded by periurban environment, which calls for an urgent evaluation on its conservation status.

Taxonomy of Atlantic Central African orchids 2. A second species of the rare genus Distylodon (Orchidaceae, Angraecinae) collected in Cameroon

While conducting field inventories in South Cameroon, we collected two specimens of a new species that we considered to belong to the genus Angraecopsis. Afterwards, a careful examination of specimens housed at main herbaria, along with the nomenclatural types, allows us to place it in Distylodon, a monotypic genus previously known from East Africa. Distylodon sonkeanum Droissart, Stévart & P.J.Cribb, sp. nov. was collected in the lowland coastal forest of Atlantic Central Africa. It is known from a single locality in the surroundings of the Campo-Ma’an National Park. The species differs from D. comptum, by its several-flowered inflorescences, longer leaves and spur, and shorter pedicel and ovary. The species appears to be rare and is assessed as Critically Endangered [CR B2ab(iii)] according to IUCN Red List Categories and Criteria. New field investigations are required to attempt to find it in the low-elevation parts of the Campo-Ma’an National Park in Cameroon.

Three new or resurrected species of Leptonychia (Sterculiaceae- Byttneriaceae-Malvaceae) from West-Central Africa

The name Leptonychia kamerunensis Engl. & K. Krause is resurrected for an understorey tree of submontane forest in the Cameroon Highlands. L. subtomentosa K. Schum. is resurrected for a tree of the hilly semi-deciduous forests around Yaounde in Central Province, Cameroon. L. moyesiae Cheek, a shrub of lowland coastal evergreen forest of SE Nigeria, SW Province Cameroon and Bioko, is newly described. The taxonomic affinities and conservation status of these three species are assessed.

Structure and floristic pattern of a coastal dunes in southeastern Brazil

The Brazilian shrublands area (restinga) is composed of marine coast vegetation on Quaternary sandy plains, where the species composition can vary depending on the surrounding ecosystems. The aims of this study were to describe the structure and floristic composition of a restinga near the community of Itaúnas, in the northern part of the state of Espírito Santo, to identify any relationships between this restinga and surrounding plant formations, and to determine which are the species that occur preferentially in the coastal forests of Espírito Santo. We sampled woody plants with a diameter at breast height > 2.5 cm, excluding lianas, in 50 plots of 100 m². We selected studies of coastal forests in the states of Espírito Santo and Bahia to prepare a database that would reveal patterns of floristic variation among these areas. We used t wo-way indicator species analysis for the identification of the species that occur preferentially in the coastal forests of Espírito Santo. We identified 114 species belonging to 38 families. Species richness was greatest for Myrtaceae (26 species), followed by Fabaceae (10). The Shannon index for the study area was 3.96. The estimated total density was 3,330 individuals/ha and basal area was 32.02 m²/ha. The highest importance value (IV) was for Protium heptaphyllum (IV, 23.4), indicating that it is characteristic of the Espírito Santo restinga. The results of our floristic analysis indicate that the species composition of the Itaúnas restinga is influenced by the so-called tabuleiro forests (coastal lowland forests on Tertiary deposits), which are most common in northern Espírito Santo. This seems to be the main factor responsible for the gradual reduction in floristic similarity between the restingas in the north of Espírito Santo and those in the south of the state, each constituting a distinct floristic block. In addition, we generated lists of species that occur preferentially in the restinga and tabuleiro forests. Those lists could inform decisions regarding environmental restoration programs.

Palaeoecology of a primate-friendly, middle Eocene community from Laredo, Texas and a review of stratigraphic occurrences of Paleogene land mammals across the Gulf Coastal Plain, USA

Recent analysis of primate remains in the Casa Blanca local fauna from the late middle Eocene Laredo Formation at Laredo, Texas has shown that the fauna’s primate species diversity was greater than previously reported. Recognition of Mahgarita cf. M. stevensi provided the first record of an Old World cercomoniine species in a Uintan community in North America. The presence of three omomyids indicates that primate species diversity in the paralic Casa Blanca community was similar to that in late Uintan age faunas in both Trans-Pecos, Texas and in the Uinta Basin of Utah. Palaeoecologic evidence from associated plant, invertebrate and vertebrate remains indicates that the regional community setting was a tropical mangrove swamp fringing a lowland coastal rain forest. This late middle Eocene climate was probably similar to the early middle Eocene climate which prevailed in Germany at the time the Messel community inhabited the region. A review of stratigraphic occurrences of Paleogene land mammal remains across the Gulf Coastal Plain indicates that the Casa Blanca fauna is one of only two Paleogene land mammal communities known from Gulf Coastal deposits. These coastal land mammal occurrences provide rare opportunities to correlate Paleogene land mammal communities known from the interior of North America with strata bearing marine species.

Podocarps in Africa: Temperate Zone Relicts or Rainforest Survivors?

Podocarp distribution in Africa follows a discontinuous mountainous belt from Cameroon to Angola in the west and from Ethiopia in the northeast to the southern Cape in South Africa. Besides a relict population of Afrocarpus falcatus in coastal lowland forest in northeastern South Africa and southern Mozambique, African podocarps are generally limited to highland (Afrotemperate) regions. All podocarps are restricted to montane regions in Madagascar. Afrotemperate landscapes are characterized by a patchy mosaic of forest and grassland. Processes in the matrix, such as fire, are important drivers of forest distribution in the highland regions. Here we examine the relative performance of podocarps and angiosperms along an altitudinal gradient from temperate highlands to subtropical coastal regions in eastern South Africa. Podocarpus latifolius is a successful component of temperate highland forest, where it dominates old-growth stages. The success of podocarps is attributed to their greater longevity and ability to regenerate in shade, whereas many potential competing angiosperms are less capable of doing so. Regeneration by P. latifolius and associated angiosperms is less successful in high-light gap environments, where ferns and grasses suppress establishment. Podocarps are rare in coastal scarp forest, where the population is dominated by adult individuals. They are unable to regenerate in very deep shade (<3% daylight), which may account for the lack of P. latifolius regeneration beneath the dense canopy of coastal scarp forest. Lownutrient soils did not favor podocarps over angiosperms, although the fact that soil nutrients do not appear to be limiting and the scarcity of shade-tolerant angiosperms in forests may influence this outcome. The relative role of light and soils on angiosperm-conifer competition is unknown for lowland forest, although current evidence from montane forests suggests that under prevailing soil conditions, light is the more important axis of niche differentiation.

New Records of Phlebotomine Sand Flies (Diptera: Psychodidae) from Ecuador

The number of recorded phlebotomine sand fly species in Ecuador has nearly doubled during the past 20 years as a result of surveys. In 2005, a sand fly survey of two localities, Tiputini in the Amazon rain forest and Paraiso Escondido in the Pacific coastal lowland forest, resulted in the capture of 25 species. New records for Ecuador consisted of five species from the Amazonian region and one from Paraiso Escondido. The Amazonian species were Nyssomyia richardwardi (Ready and Fraiha), Psathyromyia dreisbachi (Causey and Damasceno), Psathyromyia runoides (Fairchild and Hertig), Trichophoromyia pabloi (Barretto, Burbano and Young), and Trichopygomyia witoto (Young and Morales). The Pacific coastal lowland species was Psathyromyia punctigeniculata (Floch and Abonnenc).

Rapid Acoustic Survey for Biodiversity Appraisal

Biodiversity assessment remains one of the most difficult challenges encountered by ecologists and conservation biologists. This task is becoming even more urgent with the current increase of habitat loss. Many methods–from rapid biodiversity assessments (RBA) to all-taxa biodiversity inventories (ATBI)–have been developed for decades to estimate local species richness. However, these methods are costly and invasive. Several animals–birds, mammals, amphibians, fishes and arthropods–produce sounds when moving, communicating or sensing their environment. Here we propose a new concept and method to describe biodiversity. We suggest to forego species or morphospecies identification used by ATBI and RBA respectively but rather to tackle the problem at another evolutionary unit, the community level. We also propose that a part of diversity can be estimated and compared through a rapid acoustic analysis of the sound produced by animal communities. We produced α and β diversity indexes that we first tested with 540 simulated acoustic communities. The α index, which measures acoustic entropy, shows a logarithmic correlation with the number of species within the acoustic community. The β index, which estimates both temporal and spectral dissimilarities, is linearly linked to the number of unshared species between acoustic communities. We then applied both indexes to two closely spaced Tanzanian dry lowland coastal forests. Indexes reveal for this small sample a lower acoustic diversity for the most disturbed forest and acoustic dissimilarities between the two forests suggest that degradation could have significantly decreased and modified community composition. Our results demonstrate for the first time that an indicator of biological diversity can be reliably obtained in a non-invasive way and with a limited sampling effort. This new approach may facilitate the appraisal of animal diversity at large spatial and temporal scales.

Lepidopteran cereal stemborers and associated natural enemies on maize and wild grass hosts in Cameroon

Abstract: In Cameroon, the noctuid Busseola fusca is the most important pest of maize. The braconid Cotesia sesamiae, which is the most common larval parasitoid of noctuid stemborers in eastern Africa, was absent on B. fusca attacking maize. Thus, it is planned to introduce several strains of the parasitoid from Kenya. Pre‐release surveys were undertaken in major maize growing areas to catalogue stemborer species, and larval and pupal parasitoids on maize and four wild host plant species. On maize, B. fusca was the predominant borer in all ecozones except for the lowland coastal forest, usually accounting for 60–99%, followed by the pyralid Eldana saccharina in the forest zone and the crambid Chilo sp. in the mid‐altitudes. Contrary to what was reported before, the noctuid Poeonoma serrata– and not B. fusca– was the predominant borer on elephant grass, constituting 70–96% of all borers. On wild sorghum in the forest zone, the noctuid Sesamia poephaga was the most abundant species, while on Panicum sp., Chilo sp. predominated. On Setaria megaphylla in the forest zone, Chilo sp. was the most abundant species followed by Busseola quadrata. Busseola fusca was scarce on all wild grass species, indicating that previous reports on the predominance of this pest species on wild host plants were the result of misidentifications. Three tachinid and 16 hymenopteran parasitoids were obtained, most of them from B. fusca and P. serrata, on maize and Pennisetum purpureum respectively. C. sesamiae was scarce and never recovered from B. fusca on maize. In view of the new findings, acceptability and suitability studies involving the different stemborer species identified from wild plant hosts are required to determine if they will form a reproductive sink or perennate C. sesamiae populations during the off‐season when maize is scarce and B. fusca is diapausing.

Deforestation and apparent extinctions of endemic forest beetles in Madagascar

Madagascar has lost about half of its forest cover since 1953 with much regional variation, for instance most of the coastal lowland forests have been cleared. We sampled the endemic forest-dwelling Helictopleurini dung beetles across Madagascar during 2002–2006. Our samples include 29 of the 51 previously known species for which locality information is available. The most significant factor explaining apparent extinctions (species not collected by us) is forest loss within the historical range of the focal species, suggesting that deforestation has already caused the extinction, or effective extinction, of a large number of insect species with small geographical ranges, typical for many endemic taxa in Madagascar. Currently, roughly 10% of the original forest cover remains. Species–area considerations suggest that this will allow roughly half of the species to persist. Our results are consistent with this prediction.

Herpetofauna, community education and logging on Choiseul Island, Solomon Islands: implications for conservation

Biodiversity in the Solomon Islands Is extremely rich, and in the Pacific is second only to Papua New Guinea. Despite this high diversity there are only rough estimates for the biodiversity of most taxa in the Solomon Islands. As part of a terrestrial biodiversity survey, we conducted nocturnal surveys for frogs in a range of habitats from 10?1 060 m on Choiseul Island. This work was carried out between June 2005 and January 2006. In addition to the nocturnal surveys, we also conducted opportunistic diurnal searches for reptiles as well as community environmental education and awareness workshops. Fifteen frog species (65% of all Solomon Island frogs) including all five endemic species, were found during our surveys of Choiseul Island. Most of the species were fairly widespread and abundant, however, four species (Discodeles bufoniformis, Palmatorrapia solomonis, Brachylodes trossulus and B. wolfi) were fairly restricted in their distribution. In addition, we found 20 reptile species during opportunistic surveys (30% of all Solomon Island reptiles Including four endemics). Important habitats on Choiseul Island based on frog species richness and abundance are mid-altitude rainforest (500?600 m), primary lowland rainforest and lowland coastal forest. Unfortunately, it is these habitats that are most threatened by logging operations on the island. In order to aid biodiversity conservation on Choiseul Island we recommend a number of activities including additional biodiversity surveys, increased community awareness and education about biodiversity and the impacts of logging, and the drawing up of a management plan including all terrestrial taxa for Choiseul Island forests.

LEPIDOPTERA DIVERSITY, FLORISTIC COMPOSITION AND STRUCTURE OF THREE KAYA FORESTS ON THE SOUTH COAST OF KENYA

Three isolated lowland coastal forest patches in Kwale District, namely Kaya Muhaka, Kaya Kinondo and Kaya Diani are classified here as “Wetter mixed semi-deciduous forest”, “Groundwater forest on coral rag” and “Maritime scrub forest”. Although they are sacred to the Digo people, different rates of disturbance were assessed. Kaya Kinondo, which represents a rare forest type along the Kenya coast, is undisturbed at least since the authors began their studies in 1994. Floristic diversity and endemism are high in all Kayas. Lepidoptera diversity is low in Kaya Kinondo, showing that an undisturbed forest does not automatically have a rich Lepidoptera fauna and that the latter does not always respond to a diverse flora. With 352 species, Lepidoptera diversity and endemism is high in Kaya Muhaka. This includes species with a western and central Africa distribution, as well as the Kenyan endemic montane subspecies Charaxes acuminatus shimbanus. Larger moths that appear to be endemic to coastal eastern Africa are presented and others have been preliminary classified as rare for coastal Kenya including species first recorded from Kenya. Two biogeographical groups of coastal forests were found among ca. 30% of the Kenyan butterfly fauna and the authors believe that a further sub-division of the “Usambara-Kwale local centre of endemism” is possible between coastal forests further inland (e.g. Kaya Muhaka) and those close to the shoreline of the Indian Ocean (e.g. Kaya Kinondo, Kaya Diani).

Hollow-bearing trees in large glider habitat in south-east Queensland, Australia: Abundance, spatial distribution and management

This study examined factors influencing the distribution of live and dead trees with large diameter hollows (&gt;10 cm) in a productive coastal lowland forest of south-east Queensland. Forest age and type, historic logging rules and topographic position influenced the distribution of live hollow-bearing trees across the landscape. Also, some tree species (Eucalyptus acmenoides, Corymbia intermedia and C. trachyphloia) contained hollows at smaller diameters than others (C. citriodora, E. siderophloia and E. fibrosa), suggesting variation in rates of hollow formation among species. The average number of live hollow-bearing trees throughout the forest was 3.4 � 0.4 per ha (mean � s.e.), which is lower than the number of hollow-bearing trees to be retained during logging operations as specified by the Queensland Code of Practice for Native Forest Timber Production. The dead hollow-bearing tree resource is therefore important, and made up 42.3% of the total hollow-bearing tree resource. Dead hollow-bearing trees were available predominantly due to intensive silvicultural treatment conducted throughout the forest &gt;50 years ago. However, the abundance of dead hollow-bearing trees appears to be influenced by fire management. If current management practices persist, it is predicted that in 50 years the dead hollow-bearing tree resource will be depleted. If so, the hollow-bearing tree resource for the Yellow-bellied Glider Petaurus australis and in particular, the Greater Glider Petauroides vofans, will be critically limited in the study area.

Protecting NSW Coastal Lowland Forest: The Central Coast Community Environment Network

Protecting NSW Coastal Lowland Forest: The Central Coast Community Environment Network

Do Tropical Storm Regimes Influence the Structure of Tropical Lowland Rain Forests?

ABSTRACTIt has been suggested that the average canopy height of Madagascar's lowland rain forests is shorter and the average tree density is greater than in other tropical lowland rain forests of the world. The cause was hypothesized to be frequent cyclone disturbances. We compared the structure of the lowland rain forests in Madagascar to the structure described in published accounts of other tropical lowland rain forests. We found that the eastern coastal lowland forests of Madagascar have short canopy heights relative to that of many other lowland tropical rain forests, and that these Malagasy forests also have relatively high tree densities. On a worldwide basis, there is a significant correlation between short forest canopies and occurrence of tropical cyclones. The association between high tree density and occurrence of tropical cyclones is valid for Africa, but the pattern does not hold up globally.RÉSUMÉII a été conjecturé que la taille moyenne de la canopée des forȩts basses ombrophiles de Madagascar est moindre, et que la densité des arbres est plus grande, que pour d'autres forȩts tropicales ombrophiles du monde. L'hypothèse a été avancée que les perturbations fréquentes des cyclones en sont la cause. Nous avons compare la structure des forȩts ombrophiles de basse altitude de Madagascar avec la structure d'autres forȩts tropicales ombrophiles du monde. La hauteur de la canopée des foréts de I'est de Madagascar est relativement plus courte que celles de beaucoup d'autres forȩts tropicales humides de basse altitudes, et la densité des arbres est relativement élevée. A l'échelle globale, il y a une relation entre courte canopée et perturbations par les cyclones. La relation entre densité des arbres et perturbations par les cyclones est validée par cette étude seulement pour le continent Africain.

Reproductive behaviour and ecology of the dendrolimneticHadrothemis scabrifrons(Odonata: Libellulidae)

Abstract Oviposition in water-filled tree holes and mating behaviour of Hadrothemis scabrifrons was observed in a lowland coastal forest in Kenya. Conforming with the predominant mode of oviposition in the Libellulidae, females of H. scabrifrons touch the water with their ovipositor while hovering above tree holes. Male behaviour is opportunistic: usually males perch and patrol in clearings away from tree holes but at exceptionally large tree holes males are territorial and guard mates. Larvae and adults were found in different seasons; the species seems to be non-seasonal.

Species composition and phytogeographical significance of an afromontane forest fragment in the Mpumalanga province, South Africa

SYNOPSIS A floristic survey of an afromontane forest fragment, Pedlar's Bush, was done as part of an effort to proclaim this forest as a national heritage site. A checklist of 245 plant taxa has been compiled for Pedlar's Bush. The phytogeographical relationship of this forest with thirteen Afromontane and Coastal Lowland forests of the region was also investigated. Results show that Pedlar's Bush consists of tree species rare and uncommon for the region. The forest is also phytogeographically important because it forms a centre where species distribution endpoints overlap. The forest contains a number of tropical afromontane species such as Cola greenwayi var. greenwayi, Allophylus chaunostachys, Aphloia theiformis and Ocotea kenyensis which have a restricted and geographically isolated distribution pattern in South Africa. Pedlar's Bush is also situated on the periphery of a number of tree species distribution patterns, such as Chionanthus foveolatus subsp. major, Garcinia gerrardii, Maytenus nemorosa and Cryptocarya transvaalensis. Pedlar's Bush forms part of a system of forest fragments that contain a number of endemic species such as Pavetta barbertonensis, Heteropyxis canescens, Bowkeria cymosa, Polystichum macleae and Streptocarpus wilmsii on the eastern Drakensberg Escarpment. Results indicated the phytogeographical importance of this and probably other forest in the region of Barberton. Conservation of Pedlar's Bush, as largest remaining fragment, must be considered of high priority.

Effects of Chronic Human Activities on Invasion of Longleaf Pine Forests by Sand Pine

Chronic human activities may result in new and permanent successional trajectories in certain ecosystems. The invasion of longleaf pine ecosystems by sand pine in the Florida Panhandle is one such change in the landscape. This study examined the spatial pattern of sand pine expansion and explored the natural and anthropogenic disturbances that fostered this invasion. Aerial photographs (1949, 1994) and Geographic Information Systems analyses confirmed sand pine expansion at Eglin Air Force Base. In 1949, there were 8,982 ha of sand pine in the southern portion of the study area near riparian and coastal lowland forests. By 1994, sand pine had expanded further upland and inland, for a total of 17,147 ha in the study area. Sand pine age data showed that this expansion had started by 1920 but increased rapidly in the 1940s. Historical accounts and structural data from stands suggest that land-use activities associated with the extraction of turpentine promoted the invasion by sand pine. Fires were suppressed in longleaf pine forests to protect turpentine trees, resulting in increased vegetation cover and decreased regeneration of longleaf pine. In addition, stands were typically harvested after turpentining, and there was little or no advanced regeneration of longleaf pine. Sand pine age histograms showed that the onset of high establishment rates (1940s) coincided with changes in land ownership and widespread fire suppression. Sand pine is likely to persist in these ecosystems due to its abundant regeneration.