106 research outputs found
Multiple Factors Maintaining High Species-Specificity in Macaranga-Crematogaster (Hymenoptera: Formicidae) Myrmecophytism: Higher Mortality in Mismatched Ant-Seedling Pairs
Myrmecophytism, a type of mutualistic symbiosis, occurs between certain species of Macaranga trees and Crematogaster ants in the tropics of Southeast Asia. Several recent studies have revealed that myrmecophytism in Macaranga-Crematogaster involves a highly species-specific partnership, but there is less specificity at the beginning of the symbiosis when ant foundress queens settle into host seedlings. However, how 'mis-matched' species combinations of ants and plants are selected against in the field has not yet been investigated. We therefore experimentally swapped foundress queens among three sympatric species of myrmecophytic Macaranga and subsequently examined growth and survival of the ants and recipient plants. Our results suggest that severe mortality occurs among ants and seedlings of unmatched pairs throughout multiple processes, such as initial worker production, early colony growth after initial worker appearance, and defense by ants against herbivores. This contributes to the maintenance of high species-specificity in Macaranga-Crematogaster myrmecophytism.ArticleSOCIOBIOLOGY. 55(3):883-898 (2010)journal articl
How Do Scale Insects Settle into the Nests of Plant-Ants on Macaranga Myrmecophytes? Dispersal by Wind and Selection by Plant-Ants
This report elucidates the process of settlement by Coccus scale insects into Crematogaster plant-ant nests formed inside the hollow stems of a myrmecophytic species, Macaranga bancana, in a tropical rain forest. We collected wafting scale insect nymphs from the canopy using sticky traps and characterized the DNA sequence of the trapped nymphs. In addition, we experimentally introduced first-instar nymphs of both symbiotic and nonsymbiotic scale insects to M. bancana seedlings with newly formed plant-ant colonies. Nymphs of symbiotic species were generally carried by ants into their nests within a few minutes of introduction. Most nymphs of nonsymbiotic species were thrown to the ground by ants. Our results suggest that in Crematogaster-Macaranga myrmecophytism, symbiotic coccids disperse by wind onto host plant seedlings at the nymphal stage, and plant-ants actively carry the nymphs landing on seedlings into their nests in discrimination from nonsymbiotic scale insects.ArticleSOCIOBIOLOGY. 59(2):435-446 (2012)journal articl
Record of Phototactic Tenebrionidae (Coleoptera) from Lambir Hills, Borneo, with description of a new genus and twelve new species
Fifty-two species of phototactic Tenebrionidae are recorded from Lambir Hills National Park and the secondary forests surrounding the park. One new genus and twelve new species are described under the following names: Anognathena gen. nov., Anognathena neraida sp. nov., Amarygmus hansbremeri sp. nov., Cleomis purpuricollis sp. nov., Cryphaeus irregularis sp. nov., Euhemicera hutanicola sp. nov., Hemicera (Hemicera) vittigera sp. nov., Hemicera (Hemicera) parca sp. nov., Pseudonautes viridinitidus sp. nov., Psydus virgulatus sp. nov., Uloma (Uloma) nyctelia sp. nov., Uloma (Uloma) sarawakensis sp. nov. and Uloma (Uloma) serripunctata sp. nov
Difference in leaf herbivory between two plant-ant taxa associating with a myrmecophytic species, Macaranga lamellata
Macaranga lamellata (Euphorbiaceae) is a myrmecophytic species that is protected against herbivorous insects by two plant-ant taxa, Colobopsis macarangae (Formicinae) and Crematogaster spp. (Myrmicinae). Although a single M. lamellata tree houses one plant-ant colony of either of the two taxa, both coexist in a population of M. lamellata in a Bornean rainforest. To elucidate the extent of herbivory damage upon M. lamellata trees associated with Colobopsis relative to trees associated with Crematogaster, we counted the number of leaf galls and measured the leaf loss area chewed by leaf-chewing insects on M. lamellata in the forest. The occurrence of gall midges was not significantly different between the trees associated with the two plant-ants, while the degree of leaf-chewing herbivory was significantly higher on Crematogaster-associated trees than Colobopsis-associated trees. The data gathered on chewing traces observed on Crematogaster-associated trees indicated that most herbivory damage was caused by a phasmid species. These results suggest that the herbivory pressures and occurrences of different herbivore species differ between Crematogaster-associated and Colobopsis-associated trees within a population of M. lamellata
Phylogeography of the Coccus scale insects inhabiting myrmecophytic Macaranga plants in Southeast Asia
Comparative historical biogeography of multiple symbionts occurring on a common host taxa can shed light on the processes of symbiont diversification. Myrmecophytic Macaranga plants are associated with the obligate mutualistic symbionts: Crematogaster (subgenus Decacrema) ants and Coccus scale insects. We conduct phylogeographic analyses based on mitochondrial cytochrome oxidase I (COI) from 253 scale insects collected from 15 locations in Borneo, Malaya and Sumatra, to investigate the historical biogeography of the scales, and then to draw comparisons with that of the symbiotic, but independently dispersing, Decacrema ants which are not specific to different Coccus lineages. Despite the different mode of ancient diversification, reconstruction of ancestral area and age estimation on the Coccus phylogeny showed that the scales repeatedly migrated between Borneo and Malaya from Pliocene to Pleistocene, which is consistent with the Decacrema ants. Just as with the ants, the highest number of lineages in the scale insects was found in northern northwest Borneo, suggesting that these regions were rainforest refugia during cool dry phases of the Pleistocene. Overall, general congruence between the Plio-Pleistocene diversification histories of the symbiotic scales and ants suggests that they experienced a common history of extinction/migration despite their independent mode of dispersal and host-colonization.ArticlePopulation ecology. 52(1):137-146 (2010)journal articl
Tenebrionidae (Coleoptera) collected from fruiting bodies of polypores in Sarawak, Malaysia
Additional report of Tenebrionidae collected from fruiting bodies of polypores at eight sites, including seven national parks, in Sarawak, with descriptions of nine new species, Basides nakashizukai sp. nov., Basides ornatimarginatus sp. nov., Basides rhinoceros sp. nov., Boletoxenus persimilis sp. nov., Bolitonaeus grimmi sp. nov., Menimus (Menimus) pygmaeus sp. nov., Menimus (Menimus) sphaericus sp. nov., Neomida sarawakensis sp. nov., Pentaphyllus lambirensis sp. nov.; Three synonyms are proposed: Basides flavofasciatus Pic, 1916 = Basides bifasciatus Motschulsky, 1873; Ischnodactylus sexguttatus Gebien, 1925c = Basides trimaculatus Pic, 1916; Platydema sexpictum Kaszab, 1939 = Basides trimaculatus Pic, 1916
Through the Looking-Glass: reflection of ant-diversity in ant-mimics
Trabalho final de mestrado integrado em Medicina, apresentado à Faculdade de Medicina da Universidade de Coimbra.Todos os anos nascem cerca de 15 milhões de crianças prematuras em todo o mundo e
mais de 1 milhão morre no primeiro mês devido a várias complicações.
A sobrevivência de um prematuro é cada vez maior devido aos avanços nos cuidados
perinatais, contudo estas crianças sofrem frequentemente de morbilidade respiratória crónica.
Os recém-nascidos prematuros têm um risco aumentado de possuírem alterações na função
pulmonar durante a infância, adolescência e idade adulta, bem como um risco aumentado de
infeções respiratórias, asma e doença pulmonar obstrutiva crónica. Estes problemas
respiratórios são particularmente evidentes quando estas crianças prematuras desenvolvem
displasia broncopulmonar.
O objetivo deste trabalho passa deste modo por destacar quais as principais
complicações a nível do sistema respiratório dos nascimentos pré-termo, salientando a
importância de um correto desenvolvimento do aparelho respiratório na fase pré-natal e pósnatal.An estimated 15 million of babies are born too early every year around the world and
over 1 million die in the first month due to various complications.
Recent advances in perinatal care have increased the survival rates of preterm birth
however, this improved survival has led to an increase in significant chronic respiratory
morbidity.
The children born preterm have an increased risk of abnormal lung function during
childhood, adolescence and adulthood, as well as respiratory infections, asthma and chronic
obstructive pulmonary disease. These respiratory problems are particularly evident when
these preterm birth develop bronchopulmonary dysplasia (BDP).
The purpose of this work is thus to highlight what are the main complications in the
respiratory system due to preterm birth emphasizing the importance of a correct development
of the respiratory system in prenatal and postnatal phase
Timing of butterfly parasitization of a plant-ant-scale symbiosis
In the Southeast Asian tropics, Arhopala lycaenid butterflies feed on Macaranga ant-plants inhabited by Crematogaster (subgenus Decacrema) ants tending Coccus-scale insects. A recent phylogenetic study showed that (1) the plants and ants have been codiversifying for the past 20-16 million years (Myr), and that (2) the tripartite symbiosis was formed 9-7 Myr ago, when the scale insects became involved in the plant-ant mutualism. To determine when the lycaenids first parasitized the Macaranga tripartite symbiosis, we constructed a molecular phylogeny of the lycaenids that feed on Macaranga by using mitochondrial and nuclear DNA sequence data and estimated their divergence times based on the cytochrome oxidase I molecular clock. The minimum age of the lycaenids was estimated by the time-calibrated phylogeny to be 2.05 Myr, about one-tenth the age of the plant-ant association, suggesting that the lycaenids are latecomers that associated themselves with the pre-existing symbiosis of plant, ant, and scale insects.ArticleECOLOGICAL RESEARCH. 27(2):437-443 (2012)journal articl
Intra- and Interspecific Variations in the Balance between Ant and Non-Ant Defenses in Macaranga
Japan Science and Technology Corporation京都大学名古屋大学Proceedings : IUFRO Kanazawa 2003 "Forest Insect Population Dynamics and Host Influences"., Scedule:14-19 September 2003, Vemue: Kanazawa Citymonde Hotel, Kanazawa, Japan, Joint metting of IUFRO working groups : 7.01.02 Tree resistance to Insects | 7.03.06 Integrated management of forset defoloating insects | 7.03.07 Population dynamics of forest insects, Sponsored by: IUFRO-J | Ishikawa Prefecture | Kanazawa City | 21st-COE Program of Kanazawa University, Editors: Kamata, Naoto | Liebhold, Nadrew M. | Quiring, Dan T. | Clancy, Karen M
- …