XXX.—Trichoptera collected in Morocco by Messrs. K. H. Chapman and G. A. Bisset

Summary

The tube-building amphipod Microdeutopus gryllotalpa Costa was successfully reared through several generations in the laboratory. Females produced young at six to eight day intervals, as many as eleven broods being produced during the two-month reproductive life of a single female in the laboratory. Brood numbers increased and decreased cyclically throughout the breeding period of any one female and a maximum of 58 young in a single brood was recorded. At 21°C young moulted at five-day intervals during their early instars and at about nine to ten day intervals in their later stages. Both sexes reached sexual maturity after the ninth moult, but males continued to differentiate morphologically after attaining sexual maturity.     

Extended parental care in two endobenthic amphipods

Extended parental care is described for two endobenthic amphipods which inhabit the estuarine soft-bottoms along the Gulf of Maine. The juveniles of both amphipod species, Leptocheirus pinguis and Casco bigelowi, remain in the burrow of their mother after they hatch from the brood pouch. Several consecutive clutches of L. pinguis can inhabit the female's burrow simultaneously, but in C. bigelowi there is always only one clutch of juveniles in the burrow of the female. Larger juveniles of L. pinguis start building their own small tubes at the bottom of the female's burrow. Casco bigelowi females increase the size of their burrows during the time when the juveniles grow. The juveniles of both species leave the female's burrow at about half adult size. The major tasks of female L. pinguis and C. bigelowi during the time of extended parental care is to irrigate and maintain the deep burrow. It is hypothesized that extended parental care in L. pinguis, C. bigelowi and other tube/burrow-living peracarids is a mechanism to protect small offspring from epibenthic predation.     

Embryonic development and reproductive strategy of Pseudorchestoidea brasiliensis (Amphipoda: Talitridae) at Prainha Beach,Brazil

The embryonic development and reproductive strategy of Pseudorchestoidea brasiliensis, a talitrid amphipod of the supra- and midlittoral zones, were investigated by combining collections from June 1993 to May 1995 at Prainha, Rio de Janeiro (23°05′S and 43°25′W). The initial stage of embryonic development (I) was most frequent and was seen in about 70% of ovigerous females. Mean embryo volume in the final stage of development was almost twice that in the initial stage. Brood mortality between embryonic Stages I and IV was estimated at 11.42%. Multivoltism, continuous reproduction, low brood mortality (may be caused by better parental care with offspring) and the larger number of females than males in the population were indicated as compensating factors for the low fecundity observed in P. brasiliensis.     

Egg production of two sympatric species of Hyalella Smith, 1874 (Crustacea,Amphipoda, Dogielinotidae) in aquaculture ponds in southern Brazil

This study tests the hypothesis that sympatric species of Hyalella may show different reproductive strategies that permit their coexistence. Ovigerous females were collected monthly with nets during a 1-year period in two aquaculture trout ponds in Vale das Trutas, São José dos Ausentes County, southern Brazil. In both species there was a decrease in the number of embryos in the brood pouch during embryonic development, and an increase in egg volume. However, the two species differed in the body size of ovigerous females, number of eggs and juveniles per female, brood mortality rate, egg size and hatching size of juveniles. Egg production continued throughout the year, with the highest number of eggs produced during winter and spring by Hyalella pleoacuta, and winter, spring and autumn by Hyalella castroi. These differences in the reproductive traits of species of Hyalella may permit their coexistence in nature.     

The occurrence of the genus Ingolfiella (Crustacea,Amphipoda) in South Africa,with description of a new species

Abstract

The occurrence in South West Africa, i.e. within the confines of the Republic of South Africa, of the Amphipod genus Ingolfiella Hansen is recorded. The species is subterranean, is larger than any of the previously known species, and is described as I. opisthodorus sp. n. It is compared with I. leleupi Ruffo from the Congo and Northern Rhodesia. The majority of the specimens seem to be females although none has even a trace of oostegites or brood lamellæ. They exhibit a marked dimorphism of the first pair of pleopods, chiefly in specimens exceeding 14 mm. in body length; a juvenile form of this pair occurs in specimens measuring 12 to 14 mm. A few supposed males, among the last specimens to be collected (in June), are smaller than the supposed females but the two pairs of gnathopods are relatively larger and of a different form.     

Behavioural and morphological dimorphism of the sexes: an account of two primitively eusocial wasps

In social Hymenoptera, foraging, nest building, brood care and all other colony maintenance functions are carried out by the females while males function solely as reproductives. This asymmetry in social roles of the two sexes has led social insect researchers to focus almost exclusively on the females whereas males have remained relatively neglected. We studied two sympatric, primitively eusocial wasps, Ropalidia marginata and Ropalidia cyathiformis, and compared the morphological and behavioural profiles of males and females. Males of both species are smaller in size and weigh less compared to females. Males of the two species live in the nest for different durations. Borrowing from the ecological literature we use novel methods to compute and compare behavioural diversity and behavioural richness and show that females of both species are behaviourally richer and more diverse than the males.     

Sexual dimorphism,reproduction and diet of the casque-headed treefrog Itapotihyla langsdorffii (Hylidae: Lophiohylini)

Itapotihyla langsdorffii is a large “casque-headed” treefrog (Hylidae: Lophiohylini) found along most of the Brazilian Atlantic Forest biome. We studied some aspects of the ecology of a population of I. langsdorffii from the Estação Biológica de Santa Lúcia, in Espírito Santo State, southeastern Brazil. Itapotihyla langsdorffii shows considerable sexual size dimorphism, with females (mean snout-vent length 103 mm) being significantly larger than males (mean snout-vent length 81 mm). This species is an explosive breeder with a generalized reproductive mode and has a mean brood size of over 6000 eggs. It feeds on few, large prey, with orthopterans being the dominant items in the diet, though even smaller frogs may occasionally be preyed upon. We discuss our data, making comparisons with other Neotropical hylids, with emphasis on other species in the Tribe Lophiohylini.     

Reproductive biology of Limnoria chilensis: another boring peracarid species with extended parental care

Several boring peracarid species engage in extended parental care with parents tolerating small juveniles in their burrows, but only anecdotal observations have been reported from boring isopods of the genus Limnoria. The isopod Limnoria chilensis Menzies is frequently found in holdfasts of the macroalgae Macrocystis pyrifera (L.) C. Agardh and Durvillea antarctica (Chamisso) Hariot. In the present study, holdfasts of D. antarctica that harboured L. chilensis were carefully dissected in order to examine the association pattern of reproductive females and small juveniles. In most infested holdfasts, L. chilensis reached very high densities of 43.7 ± 3.9 (mean ± SE) individuals cm^?2 (range: 0–90 individuals cm^?2). The overall sex ratio (females:males) was close to unity (1.2). Male size varied between 1.5 and 2.6 mm body length (BL) and female size between 1.5 and 3.6mm BL. The percentage of reproductive females was low (19.7% of all females), and only the largest females (>2.6 mm BL) were reproductive. Embryo numbers ranged between six and 19 per female and a significant correlation between female BL and the number of embryos was found. Several females were found with small juveniles (0.8–1.2 mm BL) in the terminal end of their burrows. On several occasions, aggregations of similar-sized juveniles (1.0–1.5 mm BL) in their own burrows were found near a female burrow, indicating that these juveniles initiated their first individual burrows from within the maternal burrows. Some females with small juveniles in the terminal end of their burrows were either accompanied by males or they were ovigerous, indicating that they may have been in the process of producing a second brood. The fact that juveniles build their first burrows in the protection of female burrows suggests that such small juveniles have not yet developed full boring capacity. Extended parental care in this (and other boring) peracarid species represents a mechanism facilitating high juvenile survival rates. Given the highly local recruitment, it is suggested that the reproductive biology of this isopod has strong implications for Its population biology.     

Biology and life cycle of Tmetonyx similis (G. O. Sars, 1891) (Amphipoda,Lysianassidae), a scavenging amphipod from the continental slope of the Mediterranean

The present study focused on the biology and life cycle of Tmetonyx similis, a scavenging amphipod inhabiting the continental slope of the north‐western Mediterranean. All the categories of individuals were observed in the samples. The emergence of offspring occurs in successive cohorts. The lifespan of the females is longer than that of the males, but the sex ratio is strongly in favour of the males. The fecundity was found to be lower than that of the other female crustaceans present in these samples. The growth pattern was modelled. A strong correlation was observed between the length and the weight of the animals collected. Several hypotheses are proposed to explain a sex ratio in favour of males. This result may be explained by a migratory process of the females of T. similis. A comparison of the reproduction strategy is given for the three main scavenger crustacean species (amphipods and isopod) collected in this area.     

Brood protection in the stenoglossan gastropod Bullia melanoides (Deshayes)

Summary

Two individuals of the stenoglossan gastropod Bullia melanoides were found carrying egg capsules. In one, 33 capsules contained up to four early embryos; in the other, three capsules remained attached each containing one or two fully formed miniature adults. This species exhibits a form of brood protection in which the expanded foot is folded around the egg capsules to form a tubular brood pouch, and this habit is associated with the animals' occurrence on disturbed surf beaches on the tropical west coast of India.     

Mating behaviour and sexual selection in the African ball-rolling scarab Khepher platynotus (Bates) (Coleoptera: Scarabaeidae)

Mating behaviour of the ball-rolling dung beetle Kheper platynotus (Bates), adults of which are active in rainy seasons, was studied in southeastern Kenya. Male mating behaviour changed with the progression of the rainy season. In the early season when females made food balls, males attempted forced copulation with wandering and food-ball-making females on dung mounds. As the season progressed, females made brood balls, and males attempted to pair off with such females, as well as attempting forced copulation with wandering and food-ball-making females. A male who paired off with a brood-ball-making female cooperated with the female to make the ball. The male usually copulated after burying the ball (pre-copulatory mate guarding), but sometimes copulated during ball-making. In the latter case the male usually showed post-copulatory mate guarding until ball burial, but sometimes left soon after copulation. In the late season, when available females decreased because of maternal care in the underground nests, males started to make food balls to secure food resources for survival until the next rainy season. Male mate guarding involving ball-making, -rolling and -burying seemed to function to raise paternity confidence, but such assistance seemed to be less beneficial to females. Fights frequently occurred between guarding and intruding males on brood balls. Both residency and relative body sizes of fighters were important asymmetries influencing contest outcome. This seemed to result in not active but passive mate choice by brood-ball-making females.     

Biology and life cycle of Scopelocheirus hopei (A. Costa, 1851), a scavenging amphipod from the continental slope of the Mediterranean

The biology of Scopelocheirus hopei, a deep-sea (500 m) scavenging amphipod that lives on the continental slope of Mediterranean canyons, was studied. Animals were collected using a baited trap. A new method was developed for reproducibly measuring the exact length of the animals. All the categories of individuals were always present in the samples. The emergence of offspring occurs in successive cohorts. Individuals of the two sexes do not grow at the same rate: the males grow more quickly than the females, but their lifespans are shorter. The males are always less numerous than the females. Two production cycles occur. The females produce offspring all year round. The mean fecundity was found to be 218 eggs per female. The growth pattern was modelled. A strong correlation was observed between the length and the weight of the animals collected. Several hypotheses are proposed to explain the results obtained.     

Ampithoid amphipods from the South Pacific: Papua New Guinea,French Polynesia and New Caledonia

This paper documents 13 known and seven new species of Ampithoidae from three South Pacific locations: Papua New Guinea; the Austral Isles, French Polynesia; and the Loyalty Islands, New Caledonia. The new species Ampithoe ricaudyana, Ampithoe takeuchii, Cymadusa lituus, Cymadusa paradisaea, Plumithoe boulari, Sunamphitoe kanaka and Sunamphitoe tjiboui are described. http://www.zoobank.org/urn:lsid:zoobank.org:pub:590B4276-1DFA-40C1-B562-A7B5FC1E6A5C     

A review of the genus Parapenaeonella (Isopoda: Bopyridae: Orbioninae), with description of a new species from Chinese waters and synonymy of Parapenaeonella lamellata Bourdon, 1979

We report the first record of the parasitic isopod genus Parapenaeonella Shiino, 1949 from China. Two species are reported infesting penaeid shrimps; one is new to science, and another is a new record from China. The new species differs from Parapenaeonella distincta Shiino, 1949 in its widely open brood pouch, small biramous pleopods, simple barbula, and its male with midventral tubercle on the first pleomere. Information on the high morphological variability of males of P. distincta Shiino, 1949 and its new synonym, Parapenaeonella lamellata Bourdon, 1979, is presented. http://www.zoobank.org/urn:lsid:zoobank.org:pub:B3E0879E-EF5E-42EA-B062-3A6361DA1B5D     

Comparative investigation of the late embryogenesis of Leptodora kindtii (Focke, 1844) (Crustacea: Branchiopoda), with notes on types of embryonic development and larvae in Cladocera

The embryonic development of the parthenogenetic eggs of Leptodora kindtii has been investigated by observing living embryos removed from the female brood pouch. The sequence of morphological changes was analysed, as was the time at which the activity of certain organs began. The timing of these events at 20–22°C is documented. These data were compared with similar information obtained for some representatives of Ctenopoda and Anomopoda. The sequence of appearance of rudiments of organs on the ventral side of the embryos is similar in all these groups but the timing of shedding of the embryonic membranes differs. Hatching from the inner egg membranes takes place at the late metanauplius stage in Leptodora as in Ctenopoda and Cyclestherida, while in Anomopoda this stage is embryonized. The development of Leptodora is more like that of Ctenopoda than of Anomopoda. The embryos of all the above‐mentioned groups begin to grow at approximately the same morphological stage. A new scheme for the periodization of the embryogenesis of L. kindtii is proposed, which includes four well‐separated stages. Previously, the same number of developmental stages has been reported for Ctenopoda and Anomopoda. In Leptodora, as well as in Ctenopoda, the first two of these occur within the egg membranes. Cyclestheria has at least one embryonic moult and one embryonic stage more than Leptodora and other cladocerans. Embryonic stages 3 and 4 of the parthenogenetic eggs of L. kindtii represent a peculiar type of secondary larvae developing inside the female's brood pouch. The appearance of a free‐living nauplius in L. kindtii arises from its mode of hatching from the gamogenetic egg.     

Branchinecta hiberna , a new species of fairy shrimp (Crustacea: Anostraca) from western North America

Branchinecta hiberna , a new species of fairy shrimp, is described from temporary pools in the Great Basin region of south central Oregon, northeastern California, and adjacent Nevada. The new species shares several characters with Branchinecta cornigera Lynch, 1958: males bear a similar large patch of small spines on the basal segment of antenna 2, and females bear the similar robust antenna 2 with medial spur, brood pouch shape, and resting egg (cyst) morphology. The new species differs from B. cornigera in the shape of the distal segment of antenna 2 and the number and size of spines on the paired penis warts of males, and in the thoracic spine pattern and lack of dorsal cephalic projections in females. Observations on behavior and ecology of B. hiberna are discussed.     

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.     

Behaviour and habitat of Neohela monstrosa (Boeck, 1861) (Amphipoda: Corophiida) in Norwegian Sea deep water

There are few in situ observations of deep-sea macrofauna, due to the remoteness of this ecosystem. Visual surveys conducted for marine management by MAREANO, (marine area database for Norwegian waters) and the petroleum industry (by SERPENTS, scientific and environmental remotely operated vehicle partnership using existing industrial technology) have provided unique material of visual information from large areas in the Norwegian Sea. The distribution, density and behaviour of the deep-sea amphipod Neohela monstrosa (Boeck, 1861) is described based on videos and samples from the Norwegian Sea. This amphipod is common on mud bottoms at 200–2181 m depth in the area. Dense communities were found in stands of the arctic sea pen Umbellula encrinus at more than 1000 m depth where temperatures were below 0° C. The mean density of N. monstrosa observed for larger areas was 4/100 m² but densities of 15–36 individuals per m² were found in local patches. It is domicolous which is characteristic of the superfamily Corophiida and digs burrows in soft muddy bottoms primarily by using large shovel-like gnathopods to scoop the sediment out. The amphipod was observed pushing and rolling sediment balls out of its burrow, which were probably held together with amphipod silk. It digs out an upper 3 to 4 cm wide burrow with a horizontal side burrow a couple of centimetres down. Neohela monstrosa appears to feeds on newly settled detritus that it collects from the surface sediment through the use of its long antennae while the burrow is mainly used for protection against predators such as demersal fish. Newly released juveniles are probably kept in the burrow for protection. Based on the local high density of N. monstrosa together with its habit of making long burrows, we suggest that there is significant bioturbation associated with the presence of N. monstrosa in deep sedimentary habitats of the Norwegian Sea, which likely provides an important ecosystem function.     

Reproductive features of three maternal-caring species of Leptodactylus (Anura: Leptodactylidae) with a report on alloparental care in frogs

We describe aspects of the reproduction of three shoaling/maternal-caring Leptodactylus species (Leptodactylus aff. latrans, Leptodactylus podicipinus and Leptodactylus aff. leptodactyloides), pointing to the relevance of the female to tadpoles and describe a case of alloparental care in frogs. Females of the three species connected water bodies by digging channels to their tadpoles. Leptodactylus aff. latrans females often expelled predatory snakes and conspecific males that approached shoals to prey upon tadpoles. In water bodies containing predatory teleosts, tadpoles of L. aff. latrans only reached metamorphosis in the presence of guardian females. Channel digging can provide tadpoles with access to new feeding grounds and prevent predation and desiccation. We found brood mixing and alloparental care between L. aff. latrans and L. podicipinus which, as in some Teleostei, may be regarded as the result of identification mistakes.