Identification of multi-component trail pheromones in the most evolutionarily derived termites, the Nasutitermitinae (Termitidae)

In the present study, trail pheromone blends are identified for the first time in termites. In the phylogenetically complex Nasutitermitinae, trail-following pheromones are composed of dodecatrienol and neocembrene, the proportions of which vary according to species, although neocembrene is always more abundant than dodecatrienol (by 25-250-fold). Depending on species, termites were more sensitive to dodecatrienol or to neocembrene but the association of both components always elicited significantly higher trail following, with a clear synergistic effect in most of the studied species. A third component, trinervitatriene, was identified in the sternal gland secretion of several species, but its function remains unknown. The secretion of trail pheromone blends appears to be an important step in the evolution of chemical communication in termites. The pheromone optimizes foraging, and promotes their ecological success. (C) 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99, 20-27.

Revision of the Neotropical termite genus Orthognathotermes Holmgren (Isoptera: Termitidae: Termitinae)

This is a taxonomic revision of the Neotropical genus Orthognathotermes Holmgren, 1910 (Termitidae, Termitinae), previously with nine species: O. aduncus, O. brevipilosus, O. gibberorum, O. heberi, O. humilis, O. insignis, O. macrocephalus, O. orthognathus and O. wheeleri. We redescribe these species and describe six new species: O. longilamina sp. nov., O. mirim sp. nov., O. okeyma sp. nov., O. pilosus sp. nov., O. tubesauassu sp. nov., and O. uncimandibularis sp. nov., based on soldiers and, when possible, imago castes along with the first description of imagos of O. wheeleri and O. heberi. We present a key for soldier identification and distribution maps for all species.

A new species of Obtusitermes (Isoptera, Termitidae, Nasutitermitinae) from South America

Obtusitermes Snyder is a genus endemic to the Neotropics, restricted to northern South America and southern Central America. Obtusitermes panamae Snyder was described from Quipo, Panama. Herein, we describe Obtusitermes formosulus, n. sp., from Venezuela and Trinidad and Tobago, based on the dimorphic soldier and polymorphic worker. These descriptions provide strong evidence that Parvitermes bacchanalis Mathews should not be included in Obtusitermes.

Sex-pairing pheromones and reproductive isolation in three sympatric Cornitermes species (Isoptera, Termitidae, Syntermitinae)

The species-specificity of pairing has been studied in three sympatric Neotropical termites: Cornitermes bequaerti, Cornitermes cumulans and Cornitermes silvestrii (Termitidae, Syntermitinae). Bioassays showed that sex attraction was highly species-specific between C. bequaerti and C cumulans but not between C. cumulans and C. silvestrii. The sex-pairing pheromone of the three species is secreted by the tergal glands of female alates. It consists of a common compound (3Z,6Z,8E)-dodeca-3,6,8-trien-1-ol. In C. bequaerti, this polyunsaturated alcohol is the only compound of the sex-pairing pheromone, whereas it is associated with the oxygenated sesquiterpene (E)-nerolidol in C. cumulans, and with (E)-nerolidol and (Z)-dodec-3-en-1-ol in C silvestrii. (3Z,6Z,8E)-Dodeca-3,6,8-trien-1-ol is responsible for sexual attraction, whereas (E)-nerolidol, which is inactive in eliciting attraction of male alates, is responsible for the species-specificity of the attraction. This is the first time that a multicomponent sex-pairing pheromone has been identified in termites. The role of (Z)-dodec-3-en-1-ol present on the surface of the tergal glands of the female alates of C. silvestrii could not be definitively determined, but it is suggested that this compound could be involved in the species-specificity of sex attraction with other sympatric species of Cornitermes. Our study shows that the reproductive isolation in termites is due to a succession of factors, as the chronology of dispersal flights, the species-specificity of sex-pairing pheromones and the species-specific recognition. (C) 2011 Elsevier Ltd. All rights reserved.

An illustrated key to the soldiers of Cyranotermes Araujo with a new species from Amazonia (Isoptera: Termitidae: Nasutitermitinae)

Until now, the Neotropical termite genus Cyranotermes was known from three species: C. timuassu Araujo, C. glaber Constantino, and C. caete Cancello. In this paper a new species, Cyranotermes karipuna, n. sp., is described and illustrated from imago, worker, and soldier castes, along with its nest. It is also provided an illustrated identification key to species of Cyranotermes, a map with the occurrence of all species, and the first description of the imago caste of Cyranotermes, based on the first description of the imago of C. timuassu, and the imago of the new species.

Neotropical termites: revision of Armitermes Wasmann (Isoptera, Termitidae, Syntermitinae) and phylogeny of the Syntermitinae

We present a comprehensive phylogenetic analysis of Syntermitinae, including representatives of all genera of the subfamily, along with all 12 species assigned formerly to the genus Armitermes Wasmann (Termitidae, Syntermitinae), and 4 new species described herein. Syntermitinae was recovered as a natural group and the hypothesis that the frontal tube indicates convergence between Syntermitinae and Nasutitermitinae was corroborated. Also, several diagnostic characters proposed in the original description of Syntermitinae are discussed. Alongside the phylogenetic study, a taxonomic revision of the Neotropical genus Armitermes was carried out, resulting in division of the genus into four genera. Taxonomic novelties are: Armitermes now includes A. armiger (Motschulsky), A. bidentatus Rocha & Cancello sp.n. and A. spininotus Rocha & Cancello sp.n.; Silvestritermes Rocha & Cancello gen.n. includes S. euamignathus (Silvestri) comb.n., S. lanei (Canter) comb.n., S. gnomus (Constantino) comb.n., S. duende Rocha & Cancello sp.n., S. minutus (Emerson) comb.n., S. almirsateri Rocha & Cancello sp.n. and S. holmgreni (Snyder) comb.n.; Uncitermes Rocha & Cancello gen.n. includes U. teevani (Emerson) comb.n.; Mapinguaritermes Rocha & Cancello gen.n. includes M. peruanus (Holmgren) comb.n. and M. grandidens (Emerson) comb.n. A new synonymy is proposed for A. cerradoensis Mathews under S. euamignathus. All soldiers are described and illustrated, as are the mandibles and digestive tract of the worker and the imago caste, when available. We provide a dichotomous key, based on soldiers, for all genera of Syntermitinae, and distribution maps and dichotomous keys, based on soldiers, for the species of Armitermes and all the new genera described herein.

Developmental Pathways in Microcerotermes turneri (Termitidae: Termitinae): Biometric Descriptors of Worker Caste and Instar

The foraging process of location and exploitation of food in complex termite societies is in part reliant upon unequal division of specific tasks amongst its members (polyethism). To conduct studies assessing the role of individuals in foraging activities it is necessary to have descriptors of worker caste and instar. Here we provide biometric descriptors of specific caste and instar for worker caste and instars of Microcerotermes turneri (Froggatt) (Termitidae: Termitinae) for the worker castes (male and female) for the identification of individuals in laboratory assays applicable across multiple nests. The use of head width for determining sex of workers was successful across multiple nests. The length of the first three flagellum segments of the antenna and tibia three could be used to determine worker instar.

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.

A mitochondrial genome phylogeny of termites (Blattodea: Termitoidae) : robust support for interfamilial relationships and molecular synapomorphies define major clades

Despite their ecological significance as decomposers and their evolutionary significance as the most speciose eusocial insect group outside the Hymenoptera, termite (Blattodea: Termitoidae or Isoptera) evolutionary relationships have yet to be well resolved. Previous morphological and molecular analyses strongly conflict at the family level and are marked by poor support for backbone nodes. A mitochondrial (mt) genome phylogeny of termites was produced to test relationships between the recognised termite families, improve nodal support and test the phylogenetic utility of rare genomic changes found in the termite mt genome. Complete mt genomes were sequenced for 7 of the 9 extant termite families with additional representatives of each of the two most speciose families Rhinotermitidae (3 of 7 subfamilies) and Termitidae (3 of 8 subfamilies). The mt genome of the well supported sister group of termites, the subsocial cockroach Cryptocercus, was also sequenced. A highly supported tree of termite relationships was produced by all analytical methods and data treatment approaches, however the relationship of the termites + Cryptocercus clade to other cockroach lineages was highly affected by the strong nucleotide compositional bias found in termites relative to other dictyopterans. The phylogeny supports previously proposed suprafamilial termite lineages, the Euisoptera and Neoisoptera, a later derived Kalotermitidae as sister group of the Neoisoptera and a monophyletic clade of dampwood (Stolotermitidae, Archotermopsidae) and harvester termites (Hodotermitidae). In contrast to previous termite phylogenetic studies, nodal supports were very high for family-level relationships within termites. Two rare genomic changes in the mt genome control region were found to be molecular synapomorphies for major clades. An elongated stem-loop structure defined the clade Polyphagidae + (Cryptocercus + termites), and a further series of compensatory base changes in this stem loop is synapomorphic for the Neoisoptera. The complicated repeat structures first identified in Reticulitermes, composed of short (A-type) and long (B-type repeats) defines the clade Heterotermitinae + Termitidae, while the secondary loss of A-type repeats is synapomorphic for the non-macrotermitine Termitidae.

The evolutionary history of termites as inferred from 66 mitochondrial genomes

Termites have colonized many habitats and are among the most abundant animals in tropical ecosystems, which they modify considerably through their actions. The timing of their rise in abundance and of the dispersal events that gave rise to modern termite lineages is not well understood. To shed light on termite origins and diversification, we sequenced the mitochondrial genome of 48 termite species and combined them with 18 previously sequenced termite mitochondrial genomes for phylogenetic and molecular clock analyses using multiple fossil calibrations. The 66 genomes represent most major clades of termites. Unlike previous phylogenetic studies based on fewer molecular data, our phylogenetic tree is fully resolved for the lower termites. The phylogenetic positions of Macrotermitinae and Apicotermitinae are also resolved as the basal groups in the higher termites, but in the crown termitid groups, including Termitinae + Syntermitinae + Nasutitermitinae + Cubitermitinae, the position of some nodes remains uncertain. Our molecular clock tree indicates that the lineages leading to termites and Cryptocercus roaches diverged 170 Ma (153-196 Ma 95% confidence interval [CI]), that modern Termitidae arose 54 Ma (46-66 Ma 95% CI), and that the crown termitid group arose 40 Ma (35-49 Ma 95% CI). This indicates that the distribution of basal termite clades was influenced by the final stages of the breakup of Pangaea. Our inference of ancestral geographic ranges shows that the Termitidae, which includes more than 75% of extant termite species, most likely originated in Africa or Asia, and acquired their pantropical distribution after a series of dispersal and subsequent diversification events.

The origins and radiation of Australian Coptotermes termites: From rainforest to desert dwellers

The termite genus Coptotermes (Rhinotermitidae) is found in Asia, Africa, Central/South America and Australia, with greatest diversity in Asia. Some Coptotermes species are amongst the world’s most damaging invasive termites, but the genus is also significant for containing the most sophisticated mound-building termites outside the family Termitidae. These mound-building Coptotermes occur only in Australia. Despite its economic and evolutionary significance, the biogeographic history of the genus has not been well investigated, nor has the evolution of the Australian mound-building species. We present here the first phylogeny of the Australian Coptotermes to include representatives from all described species. We combined our new data with previously generated data to estimate the first phylogeny to include representatives from all continents where the genus is found. We also present the first estimation of divergence dates during the evolution of the genus. We found the Australian Coptotermes to be monophyletic and most closely related to the Asian Coptotermes, with considerable genetic diversity in some Australian taxa possibly representing undescribed species. The Australian mound-building species did not form a monophyletic clade. Our ancestral state reconstruction analysis indicated that the ancestral Australian Coptotermes was likely to have been a tree nester, and that mound-building behaviour has arisen multiple times. The Australian Coptotermes were found to have diversified ∼13 million years ago, which plausibly matches with the narrowing of the Arafura Sea allowing Asian taxa to cross into Australia. The first diverging Coptotermes group was found to be African, casting doubt on the previously raised hypothesis that the genus has an Asian origin.

Recursos alimentares explorados pelos cupins (Insecta: Isoptera)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Survey of the leg exocrine glands in termites(Isoptera)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Response to orphaning in two Neotropical termites: Armitermes euamignathus and Embiratermes festivellus

In this paper we examine the potential of the termites Armitermes euamignathus Silvestri: 1901 and Embiratermes festivellus (Silvestri, 1901) (Isoptera, Termitidae, Nasutitermitinae) to produce neotenics experimentally. Three nests of the mound-building termite A. euamignathus, from the Brazilian cerrado, had their primary queens removed in August 1994. After 12 months, only one mound survived; it had a normal appearance. In this healthy, orphaned colony we found the primary king, six physogastric nymphoid female replacement reproductives, two ergatoid female replacement reproductives, 46 nymphs, several presoldiers, soldiers, workers, larvae and many eggs. These data show that neotenics in A. euamignathus may originate from both workers and nymphs, but nymphoids are produced in larger numbers. The biometric study of nymphs and nymphoids suggests that these brachypterous neotenics were derived from third instar nymphs after a single moult or from four instar nymphs after a reduction of wing bud length. A piece of an E. festivellus nest with some third instar nymphs, soldiers and workers was kept under laboratory conditions. After 12 months, the whole experimental subcolony was examined and appeared to contain two pigmented nymphoid females, two pigmented nymphoid males, only one larva, seven nymphs of the same instar, 148 workers, five soldiers and many eggs. These results also indicate the capacity of the termite E. festivellus to produce nymphoid neotenics. These neotenic females were laying eggs, but they were not physogastric after a year, unlike some nymphoids of the same species collected from natural colonies.

Reciprocal interference between ants and stingless bees attending the honeydew-producing homopteran Aetalion reticulatum (Homoptera: Aetalionidae)

We evaluated the reciprocal effects between foragers of the ants Camponotus crassus and of the stingless bees Trigona hyalinata on aggregations of the honeydew-producing treehopper Aetalion reticulatum. The interactions were observed in Bauhinia variegata (Caesalpiniaceae) and Mangifera indica (Anacardiaceae) trees. We recorded the presence/absence of each attendant species in homopteran aggregations to test if the observed co-occurrence is lower than that expected by chance. An exclusion experiment was performed in which each attendant species was excluded from aggregations in order to test if an attendant species is more likely to occupy aggregations where the other attendant is not present. We also recorded the number of individuals of each attendant species in homopteran aggregations to search for any correlation between homopteran and attendant abundances. Additionally, we performed experiments using termites (Termitidae, Isoptera) as models to verify if the attendant species have the potential to defend A. reticulatum against natural enemies. The co-occurrence of attendant species was lower than that expected by chance. Homopteran aggregations without stingless bees were more visited by ants than those in which T. hyalinata was present, and vice-versa. The abundance of stingless bees was proportional to homopteran abundance, while ants abundance was not correlated to homopteran abundance. Both attendant species attacked the natural enemies models when we glued the termites ca. 1 cm away from homopteran aggregations, but only ants removed termites glued 5-7 cm away from aggregations. We suggest that the effects of non-formicid attendants should be included as another factor influencing the costs and benefits of ant-homopteran interactions, since honeydew availability for ants also depends on the presence and behavior of interspecific attendants.