In situ occurrence of a gall midge (Insecta,Diptera, Cecidomyiidae) on fossilized angiosperm leaf cuticle fragments from the Pliocene sediments of eastern India

In situ preservation of fossil insect damage in plant fossils is an excellent tool to study the coevolution of flora and fauna through geological time, but finding both damage and the insect causing that damage in the same specimen is a very rare phenomenon. Galling is a common form of angiosperm leaf damage, which can be regarded as a kind of extended phenotype of the causal insects, essentially the gall midges, but galls usually lack remains of the insects themselves. Here we report the in situ occurrence of a gall midge (Insecta, Diptera, Cecidomyiidae) as well as its pupal exuviae on the abaxial cuticular surface of fossilized leaf cuticle fragments of Fabaceae leaves (cf. Albizia) that also bear galls, recovered from the latest Neogene (Rajdanda Formation, Pliocene) sediments of the Chotonagpur Plateau, Jharkhand, northeastern India. This Pliocene gall midge features well-preserved legs, segmented antenna with distinct and enlarged scape, elongate curved setae, and longer than broad terminal plate of the ovipositor lamellae. The in situ presence of a gall midge on a host fabaceous leaf cuticle indicates the existence of a host-ectoparasite relationship in the ancient warm and humid tropical monsoon-influenced forests of eastern India during the Pliocene. This is the first authentic fossil record of an in situ phytophagous insect of Cecidomyiidae from India, as well as southeast Asia. Although the identification of the recovered phytophagous insect associated with the fossil leaf cuticle is only possible to family level, this find reveals that such plant-insect relationships existed in the Pliocene of eastern India.     

The life cycle ofAcetabularia (Dasycladales,Chlorophyceae): A compilation of evidence for meiosis in the primary nucleus

Summary The life cycle ofAcetabularia is described with special reference to nuclear divisions. Recent arguments, derived from the fields of cytology, genetics and systematics are in favour of the hypothesis, that meiosis occurs during the division of the primary nucleus. This hypothesis is summarized in a schematical representation of the whole life cycle.     

Giant ants from the Paleogene of Denmark with a discussion of the fossil history and early evolution of ants (Hymenoptera: Formicidae)

Pachycondyla rebekkae sp. nov. (Formicidae, Ponerinae) is described from the Fur and Ø1st Formations (transitional between Paleocene and Eocene, Denmark). About 95 complete or fragmentary gyne specimens and one almost complete male specimen were examined, revealing characters which permit classification and placement of the fossil species in the phylogenetic system of extant Formicidae. The palaeoecology and taphonomy of the insect fauna of the Fur and Ø1st Formations are discussed. Finally, the significance of the new species is discussed in light of the fossil history and early evolution of ants.     

Morphology and life cycle of a new loriciferan from the Atlantic coast of Florida with an emended diagnosis and life cycle of Nanaloricidae (Loricifera)

Abstract. A new interstitial loriciferan, Nanaloricus gwenae sp. nov., is described from coarse-sand and shell-hash habitats ( Amphioxus sand), at 15–17 m depth, 6–7 miles off the coast of Fort Pierce, FL, USA. The new species is very closely related to the type species Nanaloricus mysticus found off the coast of Roscoff, France in nearly the same kind of sediment ( Dentalium sand). All life stages (Higgins larva, postlarva, and adult) in the life cycle of the new species were found through the 10-year investigation, leading to the conclusion that all species of Nanaloricidae have only a sexual reproductive cycle. The adult of the new species can be distinguished by the different body shape, the lorical spikes and sculpture, and the shape of the scalids. The postlarva has stronger longitudinal ridges on the lorical plates and the Higgins larva has toes with smaller mucrones than those of N. mysticus . An emended definition of the Nanaloricidae is provided based on the new formula of the number of rows and shape of the scalids on the introvert. The associated meiofauna found in the subtidal sand or shell hash is both abundant and diverse. Tardigrades, gastrotrichs, and kinorhynchs are among the most common associates. N . gwenae sp. nov. is represented by only eight specimens collected during a 10-year period of sampling this habitat.     

An early Oligocene fossil acorn,associated leaves and pollen of the ring‐cupped oaks (Quercus subg. Cyclobalanopsis) from Maoming Basin,South China

The ring‐cupped oaks (Quercus subg. Cyclobalanopsis) characterized by united and concentric ring‐cupped acorns, are mainly distributed in broad‐leaved evergreen forests in tropical and subtropical regions of East and Southeast Asia. Their geological history has been traced from the middle Eocene to Pleistocene. Most reports of the subgenus have been on the basis of leaves, whereas the acorns or cupules, more valuable evidence for the inter‐ and intrageneric classifications, have been relatively poorly documented. Here, we describe a new species, Quercus shangcunensis sp. nov., based on a ring‐cupped fossil acorn and pollen on the acorn, as well as Quercus sp. associated leaves, recovered from the early Oligocene Shangcun Formation of Maoming Basin, Guangdong Province, South China. The morphological and anatomical structures of these fossils confirm their attribution to the subg. Cyclobalanopsis. Quercus shangcunensis sp. nov. represents the world's first Oligocene fossil acorn and the earliest fossil acorn in China for the subgenus, indicating that the subg. Cyclobalanopsis arrived in the low latitude area of South China at least by the early Oligocene. Our fossil provides evidence that the subgenus was present in one of its modern distribution centers in the Oligocene, suggesting that the modern distribution patterns of the subg. Cyclobalanopsis most likely originated during or prior to the Oligocene.     

Biology of the mayfly <Emphasis Type="Italic">Bleptus fasciatus</Emphasis> Eaton (Insecta: Ephemeroptera,Heptageniidae), with special reference to the distribution,habitat environment,life cycle,and nuptial behavior

As the habitats of the mayfly Bleptus fasciatus (Ephemeroptera, Heptageniidae) are unique and specialized, information on the distribution and biology of the mayfly is very poor. In this article, the biology of the mayfly is described, with special reference to the distribution and life cycle: the voltinism, emergence and reproductive season, nuptial behavior (i.e., swarming), egg period, and the early stage of postembryogenesis. The life cycle of the mayfly was judged as semivoltine, in contrast to the previous interpretation. Also, the unique nuptial behavior or the swarming of the mayfly is revealed.     

Physiological energetics of a midge,Chironomus riparius Meigen (Insecta,Diptera): normoxic heat output over the whole life cycle and response of larva to hypoxia and anoxia

The rate of metabolism of laboratory reared Chironomus riparius was monitored by direct calorimetry over the entire life cycle from egg to adult stage. The metabolic response of the fourth instar larva to decreasing oxygen concentrations and anoxia was also measured. Normoxic measurements were carried out at 20°C and the hypoxic-anoxic experiments at 10°C. In larvae with body sizes ranging from 0.0028 to 0.645 mg ash-free dry mass (afdm), the rate of heat dissipation was related to body mass by a power function, with a mass exponent of 0.71±0.02 corresponding to an exponent of -0.29 for the relationship between mass-specific metabolic rate and body mass. However, the allometric equations applicable to larvae would not predict the metabolic rates of eggs, pupae and adults. Single egg batches used in the experiments consisted of 354±90 eggs, the individual egg with a mass of 0.99±0.01 g (mean±SD). The mass-specific rate of heat dissipation of the egg (13.7±1.8 W mg^-1 afdm) was considerably lower than that of the first and second instar larvae (44–53 W mg^-1) but equal to that of fourth instar larvae (13.1±3.9 W mg^-1). Heat dissipation by a pupa shortly before adult emergence was high (14.8±1.8 W mg^-1), probably due to high metabolism during metamorphosis. Emergence of the adult in the calorimeter was indicated by a short but intense burst of heat. The newly emerged imago had a ca. 20–35% higher metabolic rate than the pupa. In response to reduced O₂ partial pressure the fourth instar larva of C. riparius displayed metabolic regulation. In continuously declining oxygen partial pressure, the fourth instar larva maintained its aerobic energy metabolism (4.2 W mg^-1) with only a small decrease down to 0.8 kPa, corresponding to an oxygen concentration of 0.42 mg O₂l^-1 H₂O. Below this critical oxygen concentration (P_c), the rate of heat dissipation decreased rapidly down to the anoxic level which was only 14–17% of the normoxic level. The high relative reduction of metabolic rate under anoxia gives a wrong impression of short-term tolerance of C. riparius to anoxia. The absolute energetic costs of C. riparius associated with anaerobic energy metabolism (0.64±0.11 W mg^-1) are almost 6 times higher than those of more anoxia tolerant invertebrates such as sphaeriid bivalves.     

Rugopharynx rosemariae new species (nematoda: Pharyngostrongylidae) from grey kangaroos (Macropus gig anteus and M. fuliginosus) with life cycle stages and associated pathology

Beverdge I. and Ppresidente P. J. A. 1978. Rugopharynx rosemarie sp. nov. (Nematoda: Pharyngostrongylidae) from grey kangaroos (Macropus giganteus and M. fuliginosus) with life cycle stages and associated pathology. International Journal for Parasitology8: 379–387. Rugopharynx rosemariae new species is described from the stomachs of grey kangaroos, Macropus giganteus Shaw, 1790 and Macropus fuliginosus (Desmarest, 1817) from south-eastern Australia. The new species differs from other species of the genus in spicule length and in the length and shape of the oesophagus. Parasitic life-cycle stages are described from natural infections; free-living life-cycle stages were obtained by culturing eggs from gravid females. Third stage larvae burrow into the gastric mucosa producing small elevated nodules resulting from a localized fibroplastic and inflammatory reaction in the lamina propria and submucosa. Fourth stage and adult worms occur in the stomach lumen. Rugopharynx brevis (Canavan, 1931) is made a synonym of Rugopharynx australis (Mönnig, 1926).     

A new long-proboscid genus of Pseudopolycentropodidae (Mecoptera) from the Middle Jurassic of China and its plant-host specializations

We describe a new genus and species of Mecoptera with siphonate mouthparts, Sinopolycentropus rasnitsynigen. et sp. n., assigned to the family Pseudopolycentropodidae Handlirsch, 1925. The specimen was collected from late Middle Jurassic nonmarine strata of the Jiulongshan Formation in Inner Mongolia, northeastern China. The new material provides additional evidence for an early diversification of pseudopolycentropodids that was ongoing during the Middle Jurassic. This diversity also adds to the variety of known pseudopolycentropodids with tubular proboscides that apparently fed on ovulate fluids produced by Mesozoic gymnosperms.     

Estimating index of population trend by re-sampling techniques (jackknife and bootstrap) and its application to the life table study of rice leaf roller, Cnaphalocrocis medinalis (Lepidoptera: Pyralidae)

Taking a published natural population life table of rice leaf roller, Cnaphalocrocis medinalis (Lepidoptera: Pyralidae), as an example, we estimated the population trend index, I, via re‐sampling methods (jackknife and bootstrap), determined its statistical properties and illustrated the application of these methods in determining the control effectiveness of bio‐agents and chemical insecticides. Depending on the simulation outputs, the smoothed distribution pattern of the estimates of I by delete‐1 jackknife is visually distinguishable from the normal density, but the smoothed pattern produced by delete‐d jackknife, and logarithm‐transformed smoothed patterns produced by both empirical and parametric bootstraps, matched well the corresponding normal density. Thus, the estimates of I produced by delete‐1 jackknife were not used to determine the suppressive effect of wasps and insecticides. The 95% percent confidence intervals or the narrowest 95 percentiles and Z‐test criterion were employed to compare the effectiveness of Trichogramma japonicum Ashmead and insecticides (powder, 1.5% mevinphos + 3% alpha‐hexachloro cyclohexane) against the rice leaf roller based on the estimates of I produced by delete‐d jackknife and bootstrap techniques. At α= 0.05 level, there were statistical differences between wasp treatment and control, and between wasp and insecticide treatments, if the normality is ensured, or by the narrowest 95 percentiles. However, there is still no difference between insecticide treatment and control. By Z‐test criterion, wasp treatment is better than control and insecticide treatment with P‐value < 0.01. Insecticide treatment is similar to control with P‐value > 0.2 indicating that 95% confidence intervals procedure is more conservative. Although similar conclusions may be drawn by re‐sampling techniques, such as the delta method, about the suppressive effect of trichogramma and insecticides, the normality of the estimates can be checked and guaranteed, and the correlation among sequential life stages of rice leaf roller is also considered in the estimation. Judged by the P‐values from Z‐test, the delta method is more conservative.     

Assessment of the exposure pathway in the uptake and distribution of americium and cesium in cuttlefish (Sepia officinalis) at different stages of its life cycle

Laboratory radiotracer experiments were performed to study the uptake, assimilation and retention of americium (²⁴¹Am) and cesium (¹³⁴Cs) by the common cuttlefish Sepia officinalis. Uptake and loss kinetics of the radionuclides were measured following exposure through sediments, seawater and food at different stages of the animal's life cycle. Sediment was found to be a minor uptake pathway for both radionuclides in juveniles. Following a short seawater exposure, cuttlefish accumulated ²⁴¹Am and ¹³⁴Cs, but only to a limited extent (whole-body CF < 2). Among the cuttlefish organs, branchial hearts and their appendages displayed the highest degree of uptake for ²⁴¹Am (CF = 42 and 16, respectively), but these tissues contained low percentage of total ²⁴¹Am due to their relatively small contribution to whole organism weight. The major fraction of incorporated radionuclides was associated with muscular tissues (viz. 65% and 82% of total ²⁴¹Am and ¹³⁴Cs, respectively). Whole-body loss of ²⁴¹Am and ¹³⁴Cs was relatively rapid (T_b½ = 14 and 6 days, respectively). After dietary exposure, around 60% and 30% of ingested ²⁴¹Am was assimilated into the tissues of juvenile and adult cuttlefish, respectively. However, assimilated ²⁴¹Am was more strongly retained in adults than in juveniles (T_b½ = 28 vs. 5 days, respectively), suggesting that different mechanisms govern ²⁴¹Am elimination at both ages. Ingested ¹³⁴Cs was assimilated to a similar extent in juveniles (29%) and adults (23%), but the depuration rate was four times faster in adults. Our results strongly suggest that these two radionuclides follow different excretion pathways and that the mechanisms can vary with age for a given radionuclide.     

A new species of Gorgoderina (Digenea: Gorgoderidae) from Rana berlandieri in Los Tuxtlas tropical rainforest,Mexico, with the elucidation of its life cycle

Species in the genus Gorgoderina Looss, 1902 are parasites of the urinary bladder of amphibians and include around 50 species described globally. Molecular data on species of the genus are scarce, as is the information of their life-cycle patterns. During a survey on the genetic characterization of the frog trematodes in the tropical rain forest of Los Tuxtlas, in the Gulf of Mexico slope of Mexico, specimens of two morphotypes of Gorgoderina were sampled from the Rio Grande leopard frog, Rana berlandieri. One of them represented an undescribed species which is described herein as Gorgoderina rosamondae n. sp., whereas the other one was morphologically very similar to an apparently widely distributed North American species, G. attenuata, which has been previously reported in the same geographical area. Specimens of both morphotypes were sequenced for two nuclear and one mitochondrial genes. Phylogenetic trees corroborated the distinction of the new species, and data on the internal transcribed spacer 2 revealed genetic differences between G. attenuata sequenced from frogs in USA and specimens of Gorgoderina sp. from Los Tuxtlas, indicating the possibility that they also represent an undescribed species. COI sequences showed high genetic divergence values between the new species and Gorgoderina sp. from Los Tuxtlas (8.63–9.99%). Additionally, COI sequences of the larval forms (sporocyst, cercariae and metacercariae) sampled in the same locality from their first and second intermediate hosts (Pisidium sp. and Agriogomphus tumens, respectively) showed conspecificity, and the 3 host life-cycle of the new species was elucidated.     

Re-evaluation of reproductive cycle and fecundity of finetooth sharks Carcharhinus isodon (Valenciennes 1839) from the Northwest Atlantic Ocean,with new observations on ovarian cycle and reproductive endocrinology of biennially reproducing sharks

To provide updated information on life history for improved fishery management, the reproductive cycle of the finetooth shark Carcharhinus isodon from Northwest Atlantic (NWA) populations was investigated by examining temporal changes in morphology and histology of reproductive organs. Changes in plasma concentrations of gonadal sex hormones in relation to reproductive stage were also examined. Increases in testis width, epididymis head width, plasma testosterone concentrations and occurrence of mature spermatozoa were observed in male sharks between December and April, suggesting a seasonal pattern in reproduction that culminates with copulatory activity in May. Increases in maximum follicular diameter, oviducal gland width, plasma 17β-estradiol concentrations and occurrence of vitellogenic follicles were observed in non-pregnant female sharks during the same time period along with the occurrence of newly pregnant females in May, demonstrating strong synchronicity between male and female reproductive cycles. Pregnant females bearing full-term embryos were also observed in May, indicating that parturition occurs between mid-May and early June and gestation requires 12 months. Only transient temporal changes in follicle size and oviducal gland width were observed in pregnant females, indicating that reproductive periodicity is biennial; nonetheless, a single female exhibiting signs of concurrent vitellogenesis and pregnancy was observed. Mean brood size ± S.D. was 3.9 ± 0.9 offspring/female. Fecundity was not significantly correlated with female size, in part due to an unexpectedly high rate of early embryo mortality, which occurred in 11% of pregnant females, and was more common in larger individuals. Changes in ovarian activity during mid-pregnancy were observed, suggesting possible roles for the ovary in regulating some aspects of early to mid-gestation. This study confirms that earlier characterizations of the reproductive cycle and fecundity in NWA finetooth sharks remain valid for use in fishery management. This study also highlights unusual features of finetooth shark pregnancy (e.g., early embryo death, mid-pregnancy changes in ovarian function) that may have broader relevance to understanding elasmobranch reproduction.     

A redescription of Antispastis clarkei Pastrana (Lepidoptera,Glyphipterigidae) immature stages,with notes on the life history and phylogenetic placement of the genus

Antispastis Meyrick, 1926 is a poorly known genus of leaf-mining micromoths endemic to the Neotropics, with still uncertain taxonomic position within the Yponomeutoidea. In the present study, the egg, larva and pupa of A. clarkei Pastrana, previously known only from Argentina, are described and illustrated with the aid of optical and scanning electron microscopy. Data on life history, including histology of the mine, are also provided. Family placement of the genus is reassessed based on comparison of morphology and DNA sequences with closely related lineages. The larvae form blotch mines on the upper surface of Solanum L. (Solanaceae) leaves, feeding on palisade parenchyma in all instars. Pupation occurs outside the mine, in an inverted basket-like, large-meshed cocoon constructed on the plant surface. DNA analysis of Cytochrome oxidase I gene of A. clarkei revealed interspecific differences averaging 10% with A. xylophragma, which provided species separation matching morphological differences. Antispastis was closely related phylogenetically to Digitivalva, clustering in the Acrolepiinae together with the genera Acrolepia and Acrolepiopsis, and ultimately placed within Glyphipterigidae. The geographical distribution of A. clarkei is expanded to the Southern Atlantic forest (Rio Grande do Sul and Paraná states, Brazil).