Daily activity schedule,gregariousness, and defensive behaviour in the Neotropical harvestman Goniosoma longipes (Opiliones: Gonyleptidae)

In this paper we provide a field account of some aspects of the behavioural biology of Goniosoma longipes (Roewer), a harvestman which commonly occurs in caves in South-east Brazil. During daytime, solitary and aggregated individuals can be found resting on the cave walls. Just after sunset, however, many individuals leave the cave to forage for live and dead arthropods. Foraging individuals return to the cave before dawn. Aggregations of G. longipes contain on average 34 individuals (range 7-200), and the groups are usually found close to the water source and away from the cave entrance. The main predators of G. longipes are the spider Ctenus fasciatus Mello-Leitao (Ctenidae) and the opossum Philander opossum (L.) (Didelphidae). Upon disturbance solitary and aggregated individuals may either flee, or drop from the cave wall or vegetation. The harvestmen can also release a repugnatory liquid upon manipulation, and aggregated individuals collectively discharge this secretion toward the aggressor before fleeing. The activity schedule of G. longipes shows that individuals need to leave the cave periodically to forage, and therefore the population can be considered trogloxene. Data on the food items collected by G. longipes indicate that the harvestman is a generalist predator which also feeds on dead animal matter. Gregarious behaviour is considered relatively common among harvestmen and has been interpreted in several ways. We suggest that gregarious behaviour in G. longipes may be related with the choice of more suitable microconditions in the cave habitat and/or with group chemical defence.     

Observations on the nesting behaviour of the spider wasp Eragenia congrua (Hymenoptera: Pompilidae), with the first record of the host

We describe, for the first time, the nesting behaviour of an Eragenia spider wasp, Eragenia congrua, based on field observations in the Brazilian Amazon. This species was observed nesting in holes at the base of the trunk of a Jacaranda copaia tree and provisioning nests with both amputated and non-amputated species of undetermined Corinna sp. (Corinnidae) spiders. The spiders are carried forward and grasped at the base of the chelicerae. Nesting is gregarious with females nesting in the same small area on successive days.     

Rare fishes from the Clyde sea area

Summary

The swarming flights of 23 species of termite were observed at three localities within Brazil and data collected on the periodicity of swarms, the predators which attach the exposed termites and the defensive behaviour of the three castes of termites.

The principal predators on termites during swarming were ants at ground level and birds in the air. The defensive behaviour of workers and soldiers effectively protected the termite alates from terrestrial predators, but only the low level of light at dawn and dusk protected them from aerial predators.

Most of the termites released their alates at the beginning of the rainy season, either at dawn or at dusk and protected them from grounded predators with a ‘blanket’ cordon of workers and soldiers.

Three species of the subterranean, soldierless Anoplotermes constructed special launching towers for the release of alates and protected them from predation with these structures. Armitermes euamignathus and Cornitermes cumulans also built launching structures on their nests for alates, but showed the ‘blanket’ behaviour of most termitids in their defence.

The towers constructed by the three species of Anoplotermes indicated, by their distribution and number, the density and approximate size of the subterranean colonies which built them. A mean density of 240 nests ha^-1 and 258·24 termites m^-2 was estimated for Anoplotermes sp I.     

Assembly of Myrmelachista Roger (Formicidae: Formicinae) in twigs fallen on the leaf litter of Brazilian Atlantic Forest

The nests of Myrmelachista are found in tree trunk cavities and branches. The biology of these arboreal ants is still relatively unknown. We investigated the nesting behaviour of this genus in fallen dry twigs in the Atlantic rainforest of southeastern Brazil. Physical characteristics of the nests, colony demographics, presence of breeders and ant worker sizes were recorded. Samples were collected weekly for 12 months, along open, sunny and undisturbed trails within forest remnants. In all, 202 nests were collected and six species were recorded. Myrmelachista ruszkii had the highest population of immatures and the greatest number of nests found. Myrmelachista nodigera had the smallest workers, was the least populous and the colony was housed in the finest branches. These results expand the current knowledge about the diversity and biology of Myrmelachista in the Brazilian Atlantic forest, and describe polydomic nests and competitive behaviour of M. ruszkii.     

New trophobiotic symbioses of ants with South East Asian Bugs

A trophobiotic relationship between two species of phloem-feeding plataspid bugs and an ant, Meranoplus mucronatus, was discovered on tree trunks in Malaysia. Similar relationships were found between coreid bugs and Crematogaster sp. and Anoplolepis longipes, on bamboo in the same area. The ants recruit to groups of the bugs and feed on the liquid, sugar-rich faeces of the larvae, stimulating release of the honeydew by tactile signals. They protect all stages of the bugs from disturbance by biting and by the use of defensive scretions. Phloem-feeding bugs in the families Plataspidae and Coreidae need long stylets to pierce the thick bark of their host tree. The different methods of accommodating the resting stylets in these two families are described. The plataspids are described as Tropidotylus servus sp. nov. and T. minister sp. nov. A coreid previously reported in association with M. mucronatus in Malaya is described as Hygia cliens sp. nov. The coreids on bamboo were determined as Cloresmus spp. and Notobitus affinis.     

Carton nest building and trophobiont manipulation in the south-east Asian ant Dolichoderus sulcaticeps (Mayr 1870) (Hymenoptera: Formicidae)

Dolichoderus sulcaticeps, a rare canopy living dolichoderine ant, was studied in the rainforest of Malaysia. It forms large polycalyc colonies comprising partial nests on trees and climbers. The three dimensional multichambered partial nests are situated on the leaf underside. Fibrous nest material is gathered from the surface of the nesting plants and soaked with water from the plant surface. Building activity, therefore, is strictly dependent on the presence of rainfall or dew. Within the cell with plant leaf surface contact, as well as on free feeding sites, non specific coccid and membracid throphobionts, are tended. Free feeding sites are permanently protected. Mealybugs are transported between existing and new free feeding sites, as well as to and from nest pavilions, especially during their construction or destruction. Prey hunting has not been observed in D. sulcaticeps. The workers, however, recruit to offered dead prey, and scavenged. During the day they were permanently on the surface of plants around their nests and feeding sites.     

Abundance and diversity of decapod crustaceans in the deep-Catalan Sea (Western Mediterranean)

The deep-slope decapod fauna of the Catalan Sea was extensively sampled with an OTSB-14 bottom trawl. A total of 67 bottom tows were taken from 1985 to 1989 at bottom depths ranging from 552 to 2261 m. Species in which abundance decreased with depth were Plesionika acanthonotus, Polycheles typhlops, Calocaris macandreae and Geryon longipes. Highest densities of Acanthephyra eximia, Stereomastis sculpta, and Nematocarcinus exilis were attained at the greatest depths studied. Total abundance, biomass and species richness for decapod crustaceans as a whole decreased with depth. Maximum decapod biomass and diversity occurred on the upper-middle slope on soft bottoms in the Catalan Sea and in all regions for which data were available. In the Catalan Sea, an oligotrophic area, the abundance of decapods as a group seemed to be higher than in north-Atlantic eutrophic regions. In these latter areas, other deep-sea benthic invertebrate groups, particularly ophiuroids, predominate.     

Hatching phenology,life history and population dynamics of the Oriental clam shrimp Eulimnadia indocylindrova Durga Prasad and Simhachalam with notes on phenology patterns in the Spinicaudata

We studied the natural history, hatching phenology and egg bank composition of the Oriental spinicaudatan clam shrimp Eulimnadia indocylindrova Durga Prasad and Simhachalam using both field studies and ex situ sediment rehydration. Field observations revealed that hatching began very early (1–2 days) after inundation, and continued for about 5 days. Mature adults could be observed by 10 days, and they survived up to 16 days. The population showed a largely hermaphrodite-biased sex ratio (male:hermaphrodite 1:3) observed over three years, with a decrease in number of males throughout the hydroperiod. Both amphigenic and monogenic hermaphrodites were observed. The total lifetime fecundity recorded was about 300 eggs laid in multiple clutches. The egg bank composition showed a high proportion of intact eggs, indicative of predictable hydrations and low sediment adversity. Hatching began on the first day post-inundation for all successive cyclical hydration treatments, with peak hatching on days 2 and 3. Hatching rate was highest (57% of total hatching in successive cycles) for the first hydration, decreasing subsequently for the further hydrations. Hatching duration decreased with successive hydrations and was the longest (around 7 days) for the first hydration. Maximum hatching (93%) occurred in the first 10 days for the continuous hydration treatment. Overall, the total emergence of nauplii in successive hydrations was larger than that observed for the continuous hydration treatment, indicative of a risk-spreading strategy across hydroperiods. Early and concentrated naupliar emergence, along with decreased hatching durations for successive cycles, was observed for all the hydrations. A survey of literature revealed a general lack of data on hatching phenology of clam shrimps, particularly from tropical and sub-tropical regions. Based on the available data, it appears that hatching patterns, particularly high, early hatching fractions, are commonly observed in Spinicaudata species, and do not seem to differ much across biogeographical regions.     

Predation on invasive land gastropods by a Neotropical land planarian

Studies on the predatory behaviour of land planarians have focused mainly on established invasive species, while the feeding habits of non-invasive planarians are poorly understood. We analyse the predatory behaviour of Obama ladislavii, a land planarian native to southern Brazil that is common in both natural and human-disturbed areas. Observations were performed in the laboratory. Several groups of invertebrates were offered as possible prey and interactions between these invertebrates and planarians were recorded. Obama ladislavii fed on the introduced land gastropods Bradybaena similaris, Helix aspersa and Deroceras laeve, ignoring other invertebrates. Once potential prey were identified, we tested the ability of O. ladislavii to recognize and follow slime trails, and demonstrated the planarian’s ability to follow chemical trails from prey in the environment. The consumption of exotic species indicates a flexible, generalist diet that is consistent with the ability of O. ladislavii to adapt to environments altered by human activities. Thus, this species may become invasive if introduced outside of its original distribution, but it also has the potential to be used in biological control programs for pest management in its native range.     

The ontogeny description of two Neotropical species of Crotonia (Acari: Oribatida: Crotonioidea)

A remarkable new species of black fungus gnat Pnyxiopalpus roslii sp. nov., was discovered from nests of the termite Nasutitermes proatripennis in Ulu Gombak, Malaysia, and is described based on the female morphology and DNA barcodes. This is the first record of a termitophilous black fungus gnat from South-east Asia. The new species is easily distinguished from its known congeners by the degeneration of all thoracic setae into tiny setulae. This species is described as a symbiont of the host termite based on field observations and the examination of specimens. The “wing stump” structure of the new species indicates that this species has wings after eclosion and later loses them, an adaptation to a cryptic life. A second still undescribed termitophilous species of Pnyxiopalpus was observed walking in a marching column of the termite Longipeditermes longipes in Ulu Gombak.     

How Stomaphis aphids use their giant proboscides

To penetrate tree bark, arboreal aphids of the genus Stomaphis Walk. (Hemiptera: Aphididae: Lachninae) have proboscides up to three times their body length. Our observations of S. quercus (L.) complement a recent analysis of the anatomy and function of these mouthparts by clarifying how these relatively short-legged aphids move their proboscides between the resting position, pointing back, and the prognathous working position. The absence of crumenae in Stomaphis aphids and their feeding technique are discussed.     

Polygyny,oviposition, life cycle and longevity of the three subspecies of leaf-cutting ants,Acromyrmex subterraneus (Hymenoptera: Formicidae)

ABSTRACT

Research related to the comparative biology of phylogenetically close ant species has received little attention, although it is the basis for understanding the systematics of some sibling groups. The objective was to study the polygyny, oviposition, life cycle and longevity of the three subspecies of leaf-cutting ants. For that, we studied: oviposition rate – queens from three colonies were individually placed in plastic containers, and at 24-hour intervals, the laid eggs were quantified over a period of 96 hours; the workers’ life cycle – the development of immature ants was observed every 24 hours and, as a result, the duration of each stage of development was determined; the workers’ longevity – newly emerged adults were tagged and returned to the fungus chamber of their respective nests, and daily observations were made in each of the nest’s chamber. Laying rates were variable in the three queens studied, with a mean of total eggs laid of 271 for Acromyrmex subterraneus brunneus, 113 for Acromyrmex subterraneus subterraneus and 119 for Acromyrmex subterraneus molestans.The incubation period was 21.2 days in A. s. brunneus, 22.8 days in A. s. subterraneus and 20.4 days in A. s. molestans. The larval phase and pupal phase lasted on average 22.5 and 21.2 days in A. s. brunneus, 22.8 and 15.8 days in A. s. subterraneus and 17.2 and 14.2 days in A. s. molestans, respectively. Life cycle was different in the studied taxa, from 62 to 77 days in A. s. brunneus, from 59–68 days in A. s. subterraneus and from 51 to 55 days in A. s. molestans. The workers’ longevity varied between subspecies A. s. brunneus, A. s. subterraneus and A. s. molestans.     

Tapinillus longipes (Taczanowski), a web-building lynx spider from the American tropics (Araneae: Oxyopidae)

Summary

For the first time a member of the spider family Oxyopidae, Tapinillus longipes (Taczanowski), is reported to utilize a web for prey capture under natural conditions. It is suggested that this behaviour is primitive for the family Oxyopidae.     

A re-examination of 11 species of Otostigmus from the Indo-Australian region described by R. V. Chamberlin based on type specimens in the collection of the Museum of Comparative Zoology,Harvard (Chilopoda; Scolopendromorpha; Scolopendridae)

As a contribution to a revision of the scolopendromorph centipede subgenus Otostigmus of the genus Otostigmus, the type specimens of 11 species described by R. V. Chamberlin from the Indo-Australian region and in the collection of the Museum of Comparative Zoology at Harvard have been redescribed. Of these 11, six are junior synonyms of other Otostigmus species, one is a junior synonym of Rhysida longipes longipes (Newport, 1845) and one a nomen dubium. Only three, namely, Otostigmus amballae Chamberlin, 1913, Otostigmus proponens Chamberlin, 1920 and Otostigmus pamuanus Chamberlin, 1920 are valid.     

Decapod Crustacea from the International Indian Ocean Expedition (Larval and post-larval stages of Parapenaeus Smith (Penaeinae)

Summary

Developmental stages of Parapenaeus investigatoris Alcock and Anderson from second protozoea to late post-larva and an incomplete series of P. longipes Alcock and P. fissurus (Bate) are described and figured. Important generic characters of the larvae of Parpaenaeus are two pairs of supra-orbital spines in the protozoeae, a strong hepatic spine, a long dorsomedian spine on the third abdominal segment, ventromedian spines on the anterior abdominal segments and sometimes on the last thoracic segment, a pair of dorsolateral spines on the fifth and sixth abdominal segments and a median spine on the telson.

The species recorded are widely distributed in the northern Indian Ocean, particularly in the Bay of Bengal, but only two specimens were taken south of the Equator and few in the more open parts of the ocean.     

Descriptions of two new species of the genus Agathis Latreille (Hymenoptera,Braconidae, Agathidinae) from Spain,with a record of mating by one species on flowers

Two new species of the genus Agathis Latreille, A. icarus sp. n. and A. nixoni sp. n., are described from southern Spain. Both species were observed feeding on the nectar of Anacyclus clavatus (Desf.) Pers.. (Asteraceae). A. nixoni was also observed mating on flowers. Mating by parasitoids at feeding sites is discussed.     

Burrowing on borrowed time: tides in the affairs of the rabbit (Oryctolagus cuniculus)

Three transient rabbit-burrow systems with openings below the high tide mark in shelly sand at Ballochmartin Bay, Great Cumbrae Island (Scotland) established during late summer/autumn are reported. The first remained in being for <6 days prior to tidal inundation and collapse. The period of its existence followed the first hotter spell of weather experienced during 2002 locally. A second burrow, begun a month later, at a higher elevation on the beach, lasted <1 day due to mechanical collapse. A third high-shore burrow lasted 21 days. Rabbit activity along the high shore was observed directly and evidenced indirectly (by monitoring tracks). Feeding scrapes were frequently noted at the bases of Ammophila arenaria and at the roots of Potentilla anserina. The prostrate foliage and roots of Halimione (=Atriplex) glabriuscula and upright shoots of Raphanus maritimus plants were also heavily grazed. Stranded algae (mostly Fucus spp.) of different ages (from fresh to well decomposed) were also exploited and some feeding scrapes were even observed in apparently clean sand. Perhaps rabbits foraged there for comminuted seaweed fragments incorporated into the beach. The possibility of marine macroalgal consumption by rabbits having a wide choice of vascular plant species in summer appears not to have been reported before.     

XXX.—A new Cicada from Arabia

Summary

Carebara nests occur in between 2% and 10% of Macrotermes mounds, but can also occur well away from mounds. A brood of alate ants is regularly produced ready to fly in the short rains (November) but flights can also take place in the long rains (April). Male and female alates are usually produced in separate nests. After the flight, male alates seek out the females, and several males appear to mate with one female.

Dealate female ants exposed to Macrotermes workers remained passive and elicited no aggression. Fecundated female ants reared broods of about 1000 workers after 39 days in the laboratory. These workers were able to overpower, kill and eat the much larger workers of Macrotermes.     

Action of the saproxylic scarab larva Cetonia aurataeformis (Coleoptera: Scarabaeoidea: Cetoniidae) on woody substrates

The saproxylic beetle Cetonia aurataeformis Curti (Scarabaeoidea: Cetoniidae) is a common Iberian species, whose larvae develop in tree cavities feeding on wood and litter. The aim of this paper is to analyse how the larvae of this cetonid modify the woody substrate by feeding and what the ecological implications on their microhabitat could be. Thermal analysis and infrared spectroscopy have been used to study the changes suffered by different substrates, litter and wood of Betula alba and Quercus pyrenaica, after digestion by the larvae. Results show that larvae of C. aurataeformis are able to digest polysaccharides and lignin producing a residue richer in nutrients than the original substrate and with an organic structure that contains a fraction of lignin that is easier to decompose. The main conclusion is that the action of cetonid larvae on woody substrates could facilitate their use by other saproxylic organisms in natural ecosystems.