Biometrics studies of caste development in Nasutitermes coxipoensis (Isoptera; Termitidae)

A biometric study of caste development was carried out using Nasutitermes sp., by measuring the height, width, and length of the head, the length and width of the pronotum and mesonotum, and the length of the posterior tibia. These measurements were taken on 200 individuals, including larvae, nymphs, workers, pre-soldiers and soldiers. For instar separation, it was verified that the Principal Component Analysis (P.C.A.) was the most efficient methodology. Results of this analysis showed that Nasutitermes coxipoensis follows the general pattern of development presented by other Nasutitermes.

Spatial distribution of nests of Nasutitermes sp (Isoptera : Termitidae) in a Cerrado area in southeastern Brazil

The density and aggregation patterns of nests of a species of Nasutitermes were determined in an area of 12,750 m(2). We found 131 nests in this area, and the distribution pattern was regular, with a density equaling 102.74 nests per hectare. Nest volume was determined from the height and diameter of 105 nests and varied from 1.59 to 192.46 dm(3). of the colonies, 70.5% had a volume below the mean value: 51.4% of these had volumes lower than 9 dm(3). Regression between the mean volumes and the distance of the 2 nearest nests was positive and significant (P < 0.001), suggesting competition between colonies.

Reproductive mechanisms in a Nasutitermes species (Isoptera: Termitidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Growth rate of the mounds of Nasutitermes sp. (Isoptera: Termitidae)

The growth rate of mounds of Nasutitermes sp. was evaluated by taking monthly measurements of the diameter and the height of ten mounds during twelve months. Through these data, the monthly volumes were calculated for each of them and, later, a dispersion diagram between the volume of each mound and the number of days from the first observation was obtained. From this diagram, it was observed that during the 335 days of observation, the rate of growth of these mounds was null.

Biological data for the neotropical termite Nasutitermes globiceps (Isoptera: Termitidae: Nasutitermitinae)

Nasutitermes globiceps is a Neotropical termite, considered a pest in Brazil. It has been reported to cause damage to wood of buildings, transmission poles, fences, trees and stored material. Nest architecture of this arboreal Nasutitermes is described in a small area of natural vegetation of Sāo Paulo state. Polycalism and polygyny are reported as reproductive mechanisms present in the species.

Agonistic behavior of Nasutitermes sp. (Isoptera: Termitidae)

The possible existence of agonistic, intraspecific behavior, and polycalic nests was investigated for Nasutitermes sp. Aggressive tests among soldiers, workers and between soldiers and workers of different nests were carried out, and later, injury percentage was analyzed from the results of such tests. Agonistic behavior was observed in the majority of the experiments performed between individuals from different colonies. In the light of such results, it was assumed that polycalism does not exist among the nests of this species.

Filogeografia de Nasutitermes corniger (Isoptera: Termitidae: Nasutitermitinae) na região Neotropical

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Cuticular Hydrocarbons as Chemotaxonomic Characters for Nasutitermes corniger (Motschulsky) and N. ephratae (Holmgren) (Isoptera: Termitidae)

Forty-four cuticular hydrocarbon components from workers of the termites Nasutitermes corniger (Motschulsky) and N. ephratae (Holmgren) from three localities in Panama were characterized by capillary gas chromatography-electron impact mass spectrometry. Both species contain qualitatively identical homologous series of n-alkanes; 2-, 3-, 11-,13-,14-, and 15-methylalkanes; 11,15-, 12,16-, and 13,17-dimethylalkanes; and 11,15,19- and 13, 17,21-trimethylalkanes. Both species also contain a single alkene, 9-hentriacontene. The two species, however, are readily distinguished chemically by differences among the relative abundances of 11 of their major hydrocarbon components.

Borate protection of softwood from Coptotermes acinaciformis (Isoptera: Rhinotermitidae) damage: Variation in protection thresholds explained

Laboratory and field data reported in the literature are confusing with regard to “adequate” protection thresholds for borate timber preservatives. The confusion is compounded by differences in termite species, timber species and test methodology. Laboratory data indicate a borate retention of 0.5% mass/mass (m/m) boric acid equivalent (BAE) would cause >90% termite mortality and restrict mass loss in test specimens to ≤5%. Field data generally suggest that borate retentions appreciably >0.5% m/m BAE are required. We report two field experiments with varying amounts of untreated feeder material in which Coptotermes acinaciformis (Froggatt) (Isoptera: Rhinotermitidae) responses to borate-treated radiata (Monterey) pine, Pinus radiata D. Don, were measured. The apparently conflicting results between laboratory and field data are explained by the presence or absence of untreated feeder material in the test environment. In the absence of untreated feeder material, wood containing 0.5% BAE provided adequate protection from Coptotermes sp., whereas in the presence of untreated feeder material, increased retentions were required. Furthermore, the retentions required increased with increased amounts of susceptible material present. Some termites, Nasutitermes sp. and Mastotermes darwiniensis Froggatt, for example, are borate-tolerant and borate timber preservatives are not a viable management option with these species. The lack of uniform standards for termite test methodology and assessment criteria for efficacy across the world is recognized as a difficulty with research into the performance of timber preservatives with termites. The many variables in laboratory and field assays make “prescriptive” standards difficult to recommend. The use of “performance” standards to define efficacy criteria (“adequate” protection) is discussed.

Estudio de la composicion floristica y sanidad forestal de la arboleda del sector sur del campus principal de la Universidad Nacional Agraria, Managua

Con el objetivo de generar información sobre la composición florística y sobre los factores que inciden en la arboleda de la zona sur del campus principal de la Universidad Nacional Agraria, se realizó la presente investigación durante el periodo comprendido entre los meses de Agosto 2007 a Septiembre 2008. La técnica básica de toma de datos fue la inspección ocular directa del 100 % de los árboles existentes en la zona de estudio. Se pudo determinar que la arboleda del sector sur de la UNA esta constituida por un total de 761 árboles organizados en 39 especies y agrupados en 23 familias botánicas, siendo la familia mas representativa la Mimosáceas con un total de cinco especies, la especie de árbol mas abundante fue Azaridachta indica(árbol de Nim) con 271 individuos, lo que representa el 36,6 % de toda la arboleda. A nivel de la incidencia de factores bióticos sobre la arboleda se detectó la incidencia de una especie de planta parasita identificada como Struthanthus sp el cual es catalogado como un muérdago verdadero, esta planta se encontró parasitando 15 especies de árboles con una incidencia de 6 %, lo que significa 44 árboles infestados de toda la arboleda, el árbol con mayor numero de individuos afectados fue Terminalia catappa (almendro) con 9 de 20 individuos infestados. A nivel de microorganismos fue posible observas la incidencia de cuatro tipos de hongos asociados a Pestalotia sp, Colletotrichum sp, Cryphonectria cubensis y un tipo roya, así como la incidencia de bacterias fitopatógenas en cuatro especies de árboles. A nivel de insectos se encontraron 7 géneros pertenecientes a los órdenes: Coleóptera, Psocoptera, Homóptera, Thysanoptera, Isóptera e Hymenoptera, las especies lo mas relevantes fueron Nasutitermes sp y Atta cephalotes. También fue posible determinar la incidencia de dos especies de plantas epifitas Monstrera deliciosa e Hylocereus undatus(Pitahaya) y la ocurrencia de factores físicos de daño provocados por inscrustamientos de malla en tallos y podas inadecuadas. Los resultados encontrados en el estudio indican la urgencia de diseñar un plan de manejo silvicultural de la arboleda que contribuya a su mejor cuido y asegure su conservación

Mathematical models for Isoptera (Insecta) mound growth

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Survey of the leg exocrine glands in termites(Isoptera)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Anatomy of the frontal gland and ultramorphology of the frontal tube in the soldier caste of species of Nasutitermitinae (Isoptera, Termitidae)

is a predominant characteristic, conditioned by the presence of castes with different morphology, ontogeny, and development. The soldier caste is unique among social insects and it is responsible for colony defense. Soldiers belonging to the Nasutitermitinae subfamily are very peculiar, since they may be polymorphic and present a nasus in addition to either developed or vestigial mandibles. The defensive secretions of soldiers of the neotropical Nasutitermitinae have been the aim of several chemical studies, but few data exist concerning the anatomy and histology of the exocrine glands. This article presents a comparative study on the anatomy of the frontal gland of soldiers of several Nasutitermitinae species: Syntermes dirus (Burmeister), Syntermes nanus (Constantino), Constrictotermes cyphergaster (Silvestri), Nasutitermes corniger (Motschulsky) and Velocitermes heteropterus (Silvestri), with emphasis on the ultramorphology and ultrastructure of the frontal tube.

Polyethism and comparability of termite choice assays in a model system using Microcerotermes turneri (Termitidae : Termitinae): Implications for standardised testing techniques

Traditional measures of termite food preference assess consequences of foraging behavior such as wood consumption, aggregation and/or termite survivorship. Although studies have been done to investigate the specifics of foraging behavior this is not generally integrated into choice assay experiments. Here choice assays were conducted with small isolated (orphaned) groups of workers and compared with choice assays involving foragers from whole nests (non-orphaned) in the laboratory. Aggregation to two different wood types was used as a measure of preference. Specific worker caste and instars participating in initial exploration were compared between assay methods, with samples of termites taken from nest carton material and sites where termites were feeding. Aggregation results differ between choice assay techniques. Castes and instars responsible for initial exploration, as determined in whole nest trials, were not commonly found exploring in isolated group trials, nor were they numerous in termites taken from active feeding sites. Consequently the use of small groups of M. turneri worker termites extracted from active feeding sites may not be appropriate for use in choice assays.