The varied foraging mode of the subtropical eublepharid gecko Goniurosaurus kuroiwae orientalis

Insectivorous lizards usually employ one of two foraging modes, ambush ‘sit-and-wait’ or active ‘widely foraging’, but in the Gekkonomorpha the situation has been unclear. Therefore we quantified the foraging mode of the eublepharid gecko Goniurosaurus kuroiwae orientalis on Tokashikijima near Okinawajima, Japan, in September 1999. The taxon is rare, endangered and protected. On the selected semi-urban study site the gecko was confirmed as a nocturnal cursorial gecko, which also ascends trees up to 1.8 m. Foraging regimes of marked individuals, during repeated 30-min observation periods, could vary from immobility throughout, to active locomotion 84% of the time. Foraging mode was not significantly affected by sex, body length, mass or state of tail regeneration of the individuals, or by the timing of the observation. In males, at higher temperatures single moves became longer, while time allocated to moving was stable. In both sexes longer observation bouts included longer sitting pauses, which, given stable move duration, reduced the share of time spent moving and the moves per minute. Goniurosaurus kuroiwae orientalis averaged moving during 23% of the time, moving 0.39 times per minute, the moves lasting 77 s and the pauses lasting 745 s. Compared to other geckos, G. k. orientalis may be defined as a widely foraging animal, despite its mixed behaviour. This result supports the definition of the Eublepharidae as widely foraging and is compatible with two hypotheses, that early Gekkonomorpha were widely foraging or that they had an intermediate, undefined, foraging mode.     

Observations of unusual acoustic behaviour in two Australian leafhoppers (Hemiptera; Cicadellidae)

Acoustic substrate‐borne communication between hoppers has been well studied with certain patterns of acoustic behaviour considered typical. We report observations of acoustic behaviour in two Australian leafhoppers, Stenocotis depressa (Walker) and Austrolopa brunensis Evans, that are markedly atypical. Two types of unusual acoustic behaviour were observed: female–female interactions, and the transmission of an elaborate male call through direct physical contact with the female. We discuss the evolution of these acoustic displays based on our observations of these hoppers and their environments, including the potential roles of intra‐sexual competition and the carrying capacity of the plant substrate. The discovery of these unusual behaviour patterns emphasizes the need for broader surveys of the diversity of acoustic behaviour in the Hemiptera.     

Necrophagous or predators? The role of Pheidole radoszkowskii Mayr (Hymenoptera: Formicidae) on Rattus norvegicus (Berkenhout) carcasses (Rodentia: Muridae)

This study aimed to identify the feeding habit of Pheidole radoszkowskii Mayr on Rattus norvegicus (Berkenhout) carcasses, as well as whether its presence limits the occurrence of flies. Pheidole radoszkowskii exhibited more necrophagous than predatory behaviour. Its abundance was inversely proportional to that of flies, confirming that this ant species may cause lesions in carcasses and its presence limits the occurrence of flies. This work clarifies the behaviour of an ant species often encountered on carcasses.     

Two new species of nematode (Spirurida: Physalopteridae) from Australian lizards (Reptilia: Scincidae: Gekkonidae)

Two new species of physalopterid nematodes are described from a skink (Scincidae) and a gecko (Gekkonidae) from the West Australian desert. Kreisiella chrysocampa gen. et sp. nov. (Spirurida: Physaloperidae) from Egernia inornata is characterized by the possession of a row of straight parallel denticles along the medial pseudolabial margins, male caudal alae unsupported by papillae, a truncated female tail and an anteriorly-placed vulva. The original female specimen of Physaloptera heterocephala Kreis, 1940 is transferred to this genus. In Physalopteroides filicauda sp. nov. (Physalopteridae) from Nephrurus laevissimus the external apical tooth present in immature worms is represented in adults by a knob-like structure, larger on the left pseudolabium. Both sexes possess a long slender tail terminating in a small knob. The spicules are markedly dissimilar and the vulva is surrounded anteriorly and posteriorly by horizontal rows of tubercules.     

Use of space by the marsupials Gracilinanus microtarsus (Gardner and Creighton, 1989) and Marmosops incanus (Lund, 1840) in an Atlantic Forest of southeastern Brazil

The use of space by animals is determined by environmental conditions, biological and ecological adaptations and interactions and mostly by resource availability. We sampled two species of Neotropical mammals to investigate their use of different strata in Atlantic Forest habitat in Brazil, as well as the home range sizes and movements of both sexes of each species. We found no difference in home ranges and movements between the sexes and species, but we found differences in the use of strata, with Gracilinanus microtarsus mostly using the canopy and Marmosops incanus using the ground. Gracilinanus microtarsus males mostly use the understorey in the wet season and the canopy in the dry season. We believe that these patterns of strata use reflect intrinsic characteristics of the species; and the shifts in resources and interspecific competition, which are lower in the dry season, seem to be responsible for the shifts in space use observed for G. microtarsus males. We recommend studies with spool-and-line techniques or radio tracking to further test refined hypotheses regarding the use of space, including the role of territoriality in females.     

III.—Idatiella China: Two new species,with a key (Hemiptera,Miridæ)

Summary

Nine soil, freshwater, and marine species of Thecamoeba have been isolated and investigated, and nine other probably or possibly valid species were reviewed from the literature. Locomotive form/behaviour and interphase nuclear structure are adequate to distinguish all known species, and on that basis the diagnoses of several species have been clarified and questions of possible synonymy resolved.

Most known species can be placed into either a rugose or a smooth group, but it is not yet clear that the genus can be formally divided along that line.

Feeding experiments and observations on six soil and freshwater species showed interspecific differences in the kind of protozoan prey ingested. Species also differed in their rate of multiplication in culture.

One recently discovered species, T. proteoides, approaches Amoeba proteus in both morphological and cultural characteristics more than does any other known species of Thecamoeba but is clearly a member of the latter genus.     

Reproductive behaviour of the glass frog Hyalinobatrachium cappellei (Anura: Centrolenidae) in the Southern Amazon

Frog species of the Centrolenidae family exhibit a high variation in reproductive behaviours. Herein we describe the reproductive, ecological, acoustic and behavioural features of Hyalinobatrachium cappellei in Southern Amazon. Two hypotheses were also evaluated: (1) are ecological characteristics of the reproductive site related to male size and quantity of eggs and clutches? And (2) do males with one or more existing clutches at reproductive sites accumulate more new clutches than those males initially without them? This study was conducted at two streams, with sampling at 1 km each in Southern Amazon. Species reproduction occurred during the wet season and was considered prolonged breeding. Although male vocalization occurred on both the upper and underside of leaves, clutches were most often deposited on the underside of leaves. Males emitted a courtship call upon female approach. The process of female approach until oviposition lasted approximately eight hours. After oviposition, females left the breeding site while males remained near the clutch, covering it with the belly in ventral brooding behaviour. Thus, egg attendance is reported for the first time for this species. No intraspecific or interspecific aggressive behaviour was recorded. There was no relationship between habitat characteristics of the reproductive sites and male size, number of eggs and clutches. However, after 10 days of monitoring, we found evidences that parental males had a higher number of clutches than those males initially without clutches. Similar to other glass frog species, the behavioural characteristics of H. cappellei make this species an excellent model to use in evaluating the cost-effectiveness of parental care and the importance of egg attendance for offspring survival. Therefore, these data contribute towards a better understanding of the complex phylogenetic and biogeographic relationships between centrolenid lineages.     

Reproductive ecology of the glass frog Espadarana prosoblepon (Anura: Centrolenidae) in an urban forest of the Central Andes of Colombia

Population and reproductive behaviour aspects of the glass frog Espadarana prosoblepon are well known for populations from Central America, but similar information is lacking for populations from South America. We recorded the reproductive ecology of a population of the glass frog E. prosoblepon in the city of Armenia, Central Andes of Colombia. With weekly surveys with mark-recapture between December 2013 and November 2015, we monitored activity patterns and evaluated if the probability of males mating is associated to their body size or to chorus tenure (i.e. the number of nights a same individual is calling for attracting a mate). In addition, upon observing an amplexus, we recorded the behaviour of the individuals until oviposition and noted characteristics of egg clutch. We recorded 47 males and 32 females, nine amplexus events, eight ovipositions, and 21 egg clutches (35.4 ± 4.79 eggs per clutch, N = 29). Activity of males and females and the number of egg clutches were positively correlated to rainfall. Mating success of males was not associated to their body size, but it was positively associated to longer chorus tenure; clutches from large females had a higher number of eggs than clutches from small females. Oviposition occurred on average 3.76 ± 1.74 hours after we first observed the amplexus, occurring 93.1% of the time in fronds of Selaginella geniculata at an average height of 1.58 ± 0.44 m. After the oviposition, the male left the site, while the female remained between 30 and 45 min, partially covering the eggs. The reproductive behaviour of E. prosoblepon did not vary widely between a population in Costa Rica and our population in time to oviposition, and mating success of males associated to chorus tenure; however, in our study population we recorded a larger clutch size and the preference for S. geniculata fronds as oviposition substrate.     

Attachment site selection of Hydrachna and Eylais (Acari: Hydrachnellae) watermite larvae infecting Corixidae (Hemiptera: Heteroptera)

The sites of attachment of four larval watermite species were recorded from four corixid species in Lough Corrib, Ireland. Parasitic watermites exhibited preferences in respect of attachment sites on the corixid hosts and these patterns were consistent for all host species examined. Hydrachna cruenta utilized areas of the host which were in direct contact with the water, the distribution of larvae reflecting the general behaviour and microdistribution of the hosts. Hydrachna conjecta infected the ventral hemielytra with a significant asymmetrical distribution on the right hemielytron, resulting from the folding pattern of the hemielytra and the larval route of entry to the subhemielytral air space. Eylais species attached to the abdominal terga of the host, E. infundibulifera infecting the anterior two terga and E. discreta terga three and four. Cymatia bonsdorffi was not parasitized by E. infundibulifera and on this host the majority of E. discreta attached to the second abdominal tergite. Eylais species infecting small corixid hosts may avoid interference competition with H. conjecta by attaching to the left side of the abdomen. Attachment site selection may contribute towards alleviation of intraspecific and interspecific interference competition for larval growing space.     

Asymmetric larval competition between two species of neotropical foam‐nesting frogs: Leptodactylus fuscus and Engystomops pustulosus

Larval competition was investigated in foam‐nesting frogs with contrasting breeding strategies. Leptodactylus fuscus nests in burrows with moderate numbers of large eggs, mainly on dry nights; Engystomops pustulosus makes floating nests with large numbers of small eggs, mainly on wet nights. Both use the same temporary pools in open habitat over an extended breeding season. Larval growth to metamorphosis was assessed in a semi‐natural experiment and in the laboratory. Tanks contained either single species or equal numbers of both species. Inter‐specific competition was asymmetric; L. fuscus survived as well as or better in competition with E. pustulosus than in intra‐specific competition. Leptodactylus fuscus attained larger sizes with E. pustulosus present. In interspecific competition E. pustulosus showed worse survival and grew slower and to a smaller size. Outdoors, both species tolerated water temperatures that often rose to 42°C and reached metamorphosis in very short times: 14 days after oviposition in L. fuscus and 17 days in E. pustulosus.     

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.     

Foraging mode of Australolacerta rupicola (FitzSimons, 1933) (Sauria: Lacertidae): evidence of seasonal variation in an extremely active predator?

Foraging mode of the endemic Soutpansberg rock lizard (Australolacerta rupicola) was determined by (1) measuring the number of movements per minute (MPM) and the percentage time spent moving (PTM); and (2) analysing faecal samples. Furthermore, these criteria were related to diet composition, proportion of attacks initiated while moving and foraging substrate. The results are discussed in comparison to the foraging modes of 20 other lacertid species. Values for MPM and PTM as well as faecal analysis indicate an active foraging strategy for A. rupicola. Although rock living, this species mostly forages in leaf litter where it is well camouflaged while actively searching for sedentary prey. Even in comparison to other active foragers of the family Lacertidae, A. rupicola displays the prototypic behaviour of a widely foraging lizard with very high PTM and very low MPM.     

Allometry,design and constraint of body components and of shape in sea urchins

Ontogenetic allometry of body components was studied in sea urchins from the tropical and subtropical Indo-Pacific Oceans. As sea urchins grow, the body wall, lantern and gut assume relatively smaller fractions of total wet weight whereas the coelomic fluid and gonad combined become relatively larger.

During growth, height (h) changes relative to diameter (d). Species that are relatively flat when small tend to become taller and if relatively tall become flatter as they grow with convergence towards h = d/2. This relationship is associated with equal volumetric increase for equal incremental changes in diameter and height at h = d/2. There is an interspecific relationship between height allometry and maximum size. If animals have a height diameter ratio less than 1:2 when they are very small, then the flatter they are initially, the larger the potential maximum size. There is a discontinuity in the relationship close to d = d/2 so if small individuals are relatively tall (h > d/2) then potential maximum size again is large. The allometric component of maximum size adds an interesting complication to analysis of size related features in life history evolution. The significance of allometric parameters for sea urchins include adaptation (α for body wall wet weight), developmental constraint (β for height: diameter allometry), and developmental plasticity (both α and β for the wet weight of Aristotle's lantern).     

Do caterpillars of Dryas iulia alcionea (Lepidoptera,Nymphalidae) show evidence of adaptive behaviour to avoid predation by ants?

Plants bearing extrafloral nectaries can attract wasps, bugs, and mainly ants. Ants can defend plants against herbivores by treating the plant as an extension of their own territory. We evaluated the efficiency of resting sites built by Dryas iulia alcionea larvae as protection against ant predation on their host plant Passiflora suberosa. The results showed that ants on P. suberosa have significant influence on the survival of D. iulia caterpillars. The use and construction of resting sites was recorded through the fourth larval stadium. A strong inverse relationship between the number of resting sites constructed per larva and the developmental stage of the larvae was observed. Additional results suggest that the efficacy of resting sites against cursorial predators decreases with larval development. The behaviour of constructing resting sites probably evolved by natural selection. It is likely that this behaviour was important for the ancestral lineage that gave origin to Heliconiinae genera Dryas, Dryadula and Phylaethria.     

Hybridization of beaked redfish (Sebastes mentella) with small redfish (Sebastes viviparus) and diversification of redfish (Actinopterygii: Scorpaeniformes) in the Irminger Sea

We searched for Sebastes mentella and Sebastes viviparus hybrids in samples of redfish with external traits typical of S. mentella. The samples were collected in the Irminger Sea in 2007 (n = 131) and 2010 (n = 72). Hybrids were identified using MDH-2* locus coding malate dehydrogenase. Both samples contained hybrids (two and one individuals, respectively). The results of our investigations and previously published data show that interspecific hybridization may have a strong impact on the genetic structure of S. mentella in the Irminger Sea, presumably being one of the main reasons for the differentiation of allele frequencies of some genes between samples collected at different depths. This should be taken into consideration in studies of Irminger Sea redfish.     

Indirect sperm transfer and sexual differences of Erythraeus phalangioides (De Geer), (Prostigmata,Erythraeidae)

The spermatophore and morphological differences in the sexual organs of Erythraeus phalangioides (De Geer) as well as the reproductive behaviour of males are described.     

Octopus mimicking its follower reef fish

We describe a possible example of social mimicry between Octopus insularis and the small grouper Cephalopholis fulva, which frequently associate during foraging at Fernando de Noronha Archipelago, Brazil. The octopus, when swimming backwards, jet‐propelled, becomes similar in colour and shape to accompanying C. fulva individuals and is therefore less conspicuous within the fish group. We regard this as an instance of social mimicry, a form of protection against visually‐oriented predators in which different species similar in shape and colour mingle for the advantage of grouping. Even when swimming backwards alone, O. insularis may become similar to foraging C. fulva individuals, another putatively protective behaviour. We suggest that the feeding association commonly found between O. insularis and C. fulva minimized the evolutionary costs for the origin of mimicking by the octopus.     

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.