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.     

Natural history and behaviour of the primitively eusocial wasp Ropalidia marginata (Hymenoptera: Vespidae): a comparison of the two sexes

We report the natural history and behaviour of the primitively eusocial wasp Ropalidia marginata with a special reference to the males. We found that just as nests of this species are found throughout the year, so are the males. Females spend all their life in their nests but males stay in their natal nests only for 1–12 days and leave to lead a nomadic life. Males maintained in the laboratory can live for up to 140 days. Like all eusocial hymenopteran males, R. marginata males also do not perform any colony maintenance activities. We found that males did not forage or feed larvae. Compared with females, males showed fewer dominance and subordinate behaviours and being solicited behaviour and more feeding self and soliciting behaviours. By comparing males with young females, we found similar differences, except that the males showed similar rates of feeding self and higher rates of subordinate behaviour.     

Social facilitation and food partitioning in the queenless ant Dinoponera quadriceps (Hymenoptera: Formicidae)

Social facilitation occurs when an animal is more likely to behave in a certain way in response to other animals engaged in the same behaviour. For example, an individual returning to the nest with food stimulates other ants to leave and to forage. In the present study we demonstrate the existence of new facets in the colony organization of Dinoponera quadriceps: a positive feedback between the incoming food and the activation of new foragers, and the occurrence of incipient task partitioning during the food sharing. Lower-ranked workers located inside the nest process protein resources and higher-ranked workers handle smaller pieces and distribute them to the larvae. In conclusion, D. quadriceps has a decentralized pattern of task allocation with a double regulatory mechanism, which can be considered a sophisticated aspect of division of labour in ponerine ants.     

Notes on the foraging behaviour and taxonomy of the southeast Asian termite Longipeditermes longipes (Termitidae: Nasutitermitinae)

The southeast Asian termite Longipeditermes longipes (Nasutitermitinae) forages above ground during the day in highly organised columns of workers protected by numerous soldiers. Preliminary data are presented on its foraging activity, based on observations of one colony in southern Kalimantan, Borneo. Foraging columns were observed on 7 of the 15 days, including successive days interspersed with periods of inactivity. Termites marched in columns to feeding sites along trails, reusing the same trails on successive days. Trail length varied from 7.0m to 14.5m. The termites were observed feeding on leaf litter and rotting tree trunks, and the workers displayed a division of labour between gnawing plant material and carrying the fragments back to the nest. Details are provided of soldiers and workers collected from tree canopies using insecticidal fogging. One of the two other species in the genus, L. mandibulatus, is shown to be a junior synonym of L. longipes.     

Aspects of the activity rhythm and population size of troglophilic mygalomorph spiders (Trechona sp., Dipluridae) in a quartzite cave in Minas Gerais,Brazil

Records of mygalomorphs inhabiting caves have increased in the past years. We present data on a population of Trechona sp. spiders, found in a quartizite cave in Diamantina, Minas Gerais, Brazil. The spiders and their retreats were marked, and this population was followed for 17 months. The population consisted of up to 100 individuals, comprising the worlds’ largest known cave-dwelling population of mygalomophs. The estimated population size (Jolly-Seber model) varied from 50.36 to 853.43, the latter considered much overestimated. We did not find individuals of Trechona sp. in the surrounding epigean areas. The number of spiders was higher in the entrance zone than in the other two zones (twilight and dark zones). We found that individuals at the entrance zone showed similar activity to a nocturnal spider, whereas the other two groups showed conspicuous differences from this pattern, spending longer periods without rest, on the sheet-web as a sit-and-wait predator.     

Biology of a nocturnal bee,Megalopta atra (Hymenoptera: Halictidae; Augochlorini), from the Panamanian highlands

Bees of the genus Megalopta have gained attention as a result of their social nesting and nocturnal foraging. Seventeen nests of Meglaopta atra from the highlands of Chiriqui Province, Panama, were collected at the end of the dry season when brood rearing is expected to be at its peak. Most nests contained single females; within multifemale nests only one female possessed enlarged ovarioles, although some non‐reproductive individuals were inseminated. In two of these nests reproductive individuals were clearly larger in body size than nestmates, but body size variation and macrocephaly were equivalent to those found in other Neotropical augochlorines. There was no evidence of a non‐reproductive worker‐like caste and multifemale nests did not appear to be more productive than solitary nests, which may represent pre‐reproductive assemblages. Megalopta atra appears to be isolated by altitude from co‐geners common in Panama, this is discussed in comparison with temperate halictine bees, in which environmental clines separate solitary from social populations.     

Foraging ecology of the giant Amazonian ant Dinoponera gigantea (Hymenoptera,Formicidae, Ponerinae): activity schedule,diet and spatial foraging patterns

This study provides a detailed account of the natural history and foraging biology of the ponerine ant Dinoponera gigantea in a rainforest in north Brazil. The species nests on the ground and the colonies contain 70–96 workers. Ant activity is negatively correlated with temperature, and is more intense at dawn and dusk. Foragers leave the nest independently and search for food individually on the leaf litter, within ca 10 m around the nest. Workers are opportunistic feeders that collect seeds and fruits, and hunt for live prey as well as scavenge for dead animal matter. The dry weight of food items ranges from <10 mg (spiders, insect parts) to >400 mg (seeds, fruits). There is no nestmate recruitment during the search for or retrieval of food, irrespective of food type and size. Foragers have a high directional fidelity, and ants from neighbouring colonies may engage in ritualized territorial contests at the border of their foraging areas. The foraging ecology of D. gigantea is compared with other ponerine species living in tropical forests, as well as with other ant groups showing similar behavioural patterns.     

Phoretic behaviour of Attacobius attarum (Roewer, 1935) (Araneae: Corinnidae: Corinninae) dispersion not associated with predation?

Attacobius attarum spiders exhibit a phoretic behaviour on the winged sexual of Atta leaf-cutting ants during their mating flight. However, it is unclear if this behaviour is for dispersion or to facilitate the predation of ants in the new colonies. A nest of Atta sexdens was monitored on the day of the mating flight, and the winged ants, as well as the spiders, were collected. The results obtained corroborate the hypothesis that phoretic behaviour is commonly used for dispersion of the spider A. attarum, predominantly females. Of these spiders, 64 individuals of A. attarium were collected, of which 62 were females (96.9%) and two were males (3.1%). Regarding the winged leaf-cutting ants sampled, 378 females and 361 males were collected, totaling 739 individuals. Of these, 64 individuals (8.7%) had a spider attached to its back for phoretic dispersal and none was observed on the queens after the nuptial flight. In our study, A. attarum females perform phoretic dispersal into the environment on winged leaf-cutting ants but do not settle in the new nests.     

Predatory behaviour in Deltochilum: convergent evolution or a primitive character within a clade?

We present data on predatory behaviour in Deltochilum cupreicolle viridescens, which belongs to the subgenus Aganhyboma, and we contrast it with the behaviour of a species from the subgenus Deltohyboma. By this comparison we can investigate whether the predatory behaviour in Deltochilum could have appeared independently in these two subgenera, or if the behaviour is so similar that it suggests a single origin in a possible ancestor exclusive to those two groups. These laboratory studies on the behaviour of Deltochilum c. viridescens individuals on diplopods are described and divided into the following stages: (1) approach and recognition of the diplopod; (2) attack and death of the prey; (3) on-site feeding; (4) transport of the diplopod. The results found here strengthen the hypothesis of a primitive and highly specialized behaviour within a possible clade formed by the predatory species of Diplopoda.     

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.     

Nesting behaviour and prey of Pseudoplisus Ashmead (Hymenoptera: Sphecidae)

Nesting behaviour and prey of two species of Pseudoplisus, a gorytine wasp genus in the sphecid subfamily Nyssoninae, are described. P. natalensis is a solitary nester in southern Africa nesting often in the soil in flower-pots. P. ranosahae in Madagascar nests in the ground in large aggregations. Both species show a high degree of prey specificity. Nests are provisioned only with large adult froghoppers (Aphrophoridae), P. natalensis preying on Ptyelus grossus and P. ranosahae on Ptyelus goudoti.     

A collection of recent and subfossil mammals from southern Turkey (Asia Minor), including the dormouse Myomimus personatus

Summary

Living representatives of twelve species of mammal are recorded from the vicinity of Finike, south-western Asia Minor. A further six species were found in the form of skulls or skeletons, mainly on the surface of cave floors. Some of these, along with an additional eight species, were also found by excavating the floor of a cave that now opens on the face of a cliff. These were associated with artefacts suggesting that the entire deposit was formed about 5000 B.C. All the mammals from the cave deposit are of species known to be living in Asia Minor, except the dormouse Myominus personatus.

Philistomys roachi Bate, from Pleistocene and post-Pleistocene cave deposits of Israel, is shown to be a synonym of Myomimus personatus Ognev.     

Prey choice and raiding behaviour of the Ponerine ant Pachycondyla analis (Hymenoptera: Formicidae)

Termite raiding behaviour of the African poneromorph ant Pachycondyla analis was studied at Mpala, Kenya. In all, 330 raids were observed with the raiding activity showing peaks in the morning and evening. Time spent at the termite source was positively correlated with the numbers of termites taken. The sizes of foraging parties, number of termites taken, distance travelled and time spent at termite sources also showed a positive correlation. Pachycondyla analis preyed significantly more on Microtermes spp. than they did on Odontotermes spp. but no significant differences were found in terms of predator efficiency even though many ants were injured in raids on Odontotermes spp. compared with those on Microtermes spp. Our results indicate that P. analis seems to forage optimally, balancing the costs of energy with prey reward and prey choices were not only influenced by prey abundance, but also by the costs of foraging, as influenced by prey defences, size and foraging behaviour.     

Biology and life history of the araneophagic assassin bug Stenolemus bituberus including a morphometric analysis of the instars (Heteroptera,Reduviidae)

Stenolemus bituberus is an araneophagic “assassin bug” (Heteroptera; Reduviidae; Emesinae) that typically is found living in spider webs. We documented the life history of S. bituberus in the field for 13 months, determining its developmental phenology and microhabitat characteristics as well as describing its mating and predatory behaviour. We also included a morphometric analysis of the instars. Our study revealed that S. bituberus is univoltine with five juvenile instars. Although S. bituberus is found in the webs of spiders from a wide range of genera, it is found most commonly in the webs of Achaearanea, Badumna, Pholcus, and Stiphidion. Multiple juveniles often were found on a single web, but adults tended to be more solitary. Stenolemus bituberus appears to have two distinct hunting strategies: “stalking”, in which they slowly approach the spider, make contact and then strike; and “luring”, in which they attract the spider within range by manipulating the silk with their legs.     

The reproductive ecology of Leptodactylus fuscus (Anura,Leptodactylidae): new data from natural temporary ponds in the Brazilian Cerrado and a review throughout its distribution

Recent studies indicate that populations historically called Leptodactylus fuscus (Schneider, 1799) comprise at least three well‐differentiated lineages. Herein, we describe the reproductive ecology of a southeastern clade population of L. fuscus, and review the characters of the reproductive ecology for several populations of the northern and southeastern clades. Most reproductive activity occurred in December and January, which coincided with the highest rainfall period. Males had an aggregated spatial distribution in the central area of the ponds. Three courtship interactions were observed. A female was observed closing the entrance to a burrow with moist sand after oviposition. This behaviour is described for the first time in L. fuscus. The review of the reproductive biology of the northern and southeastern clades indicates a relatively high plasticity in L. fuscus. Furthermore, the results corroborate the suggestion, based on molecular data, that the northern and southeastern clades of L. fuscus represent distinct evolutionary units.     

Two new species of terrestrial Isopoda (Crustacea,Oniscidea) from Ascension Island

A collection of eight species of terrestrial isopods from lava and cave sites on Ascension Island is described. Two species, Niambia longiantennata (Platyarthridae) and Elumoides coecus (Eubelidae), are described as new. Atlantoscia alceui Ferrara and Taiti (Philosciidae) is considered to be a junior synonym of A. floridana (Van Name) and the genus Ocelloscia Schultz and Johnson of Atlantoscia Ferrara and Taiti. At present the oniscidean fauna known from Ascension Island consists of 13 species.     

Long copulations and post-copulatory ‘escort’ behaviour in the locust leaf miner,Odontota dorsalis (Coleoptera: Chrysomelidae)

The adult behaviour of Odontota dorsalis on its host plant Robinia pseudo-acacia was studied by following marked individuals in nature. Copulations often lasted several hours, and were characteristically followed by long escort phases in which males remain mounted atop females. Pairing lasted as long as several days. Most pairs broke up around the time of day when most females were ovipositing. Females normally laid a small cluster of eggs once per day. Both sexes mated repeatedly, and females did not resist copulations.

Long pairings in O. dorsalis may have evolved because the encounter rate between the sexes is high and costs to the female low. It is suggested that escort behaviour will be found in many other species with similar ecology and in which males remain mounted on females while copulating.     

Foraminiferan (Protozoa) epizoites on the anthuridean (Crustacea,Isopoda) Calathura brachiata (Stimpson)

Foraminiferan epizoites were studied on the isopod Calathura brachiata (Stimpson). Most individuals found belonged to the genus Cibicides. The foraminiferans were either rare or quite frequent on Calathura brachiata, indicating patchy occurrence of living foraminiferans. They were most frequent on the anterior part of the body (head, first pereonites) and the first two pairs of legs (pereopods). This pattern, which is unusual among foraminiferan epizoites on isopods, is explained by habitat selection of the foraminiferans and the behaviour of the isopod, which presumably rests between feeding with the anterior part of the body held in an upward position, allowing foraminiferans to settle on mouthparts and on the legs (first two pereopods) used in grasping prey. The size range of the foraminiferans indicates that settling of foraminiferans from the water column is more important for the development of foraminiferan epibiosis on Calathura than migration of individuals from the bottom and this may be the general pattern for most isopod species.     

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.