The zoeal development of Platymaia wyvillethomsoni Miers, 1886 (Crustacea: Decapoda: Majoidea: Inachidae) described from laboratory reared material

The spider crab Platymaia wyvillethomsoni was reared in the laboratory, from hatching to the megalopal stage at 20°C. The larval development comprises two zoeal stages and a megalopa. The zoeal stages are described for the first time and compared with those of the four known species of the family Inachidae from the northern Pacific. The zoeal characters (carapace spines, antenna, mouthpart appendages, pleon and telson fork) of P. wyvillethomsoni are significantly different from those of two Achaeus species from northern Pacific and other inachid genera (Inachus and Macropodia) from the Atlantic. Therefore, this species should not be placed in the family Inachidae based on zoeal morphology. A provisional key for the identification of known zoeae of the family from the northern Pacific is provided.     

Comparative morphology of larvae of coastal crabs (Crustacea: Decapoda: Varunidae)

The larval development of three crabs of the Varunidae family, (Hemigrapsus sanguineus, H. penicillatus, and H. longitarsis), widely spread in Russian waters of the Sea of Japan, were studied under laboratory conditions. At a temperature of 20–22°C and a salinity of 32‰ about 30% of larvae a complete developmental cycle, including five zoeal stages and megalopa, took from 22 to 30 days. All larval stages are illustrated and described in detail. Zoea I and zoea II of the studied crabs are not distinguishable. Zoea III–V of these species differ in the number of dorsomedial setae on the abdominal somite I and in the number of setae on the posterodorsal arch. The megalopae of three Hemigrapsus species possess a different number of segments, aesthetascs and setae on the antennular exopod. In spite of the great similarity of larvae of genera Hemigrapsus and Eriocheir, the latter possesses a number of distinctive features in all developmental stages, supporting the separation of these genera.     

Morphological features of the larvae of spider crab <Emphasis Type="Italic">Pugettia quadridens</Emphasis> (Decapoda: Majidae) from the Northwestern Sea of Japan

The entire cycle of larval development of the spider crab Pugettia quadridens (de Haan, 1850) (Decapoda: Majidae), widespread in Peter the Great Bay (Sea of Japan) is studied under the laboratory conditions. The development cycle of this species comprises prezoea, zoea I, zoea II, and megalopa. At a temperature of 18–20° C larval development took from 11 to 15 days. Zoea II is described in detail for the first time. Many morphological characters are found distinguishing zoea and megalopa of P. Quadridens in Russian waters from the larvae of this species in Japanese and Korean waters. Some characters of larvae are similar in P. Quadridens and the related species of the genus Pugettia. The larvae of P. Quadridens occur in the plankton of Vostok Bay from late June to late October with a density up to 5 ind/m³ at a surface water temperature of 13–21°C. They are easily distinguished from the other brachyuran larvae of this region by the absence of lateral spines on the carapace.Original Russian Text Copyright © 2004 by Biologiya Morya, Kornienko, Korn.     

Seasonal phenology and stage-specific parasitism of the apple ermine moth, Yponomeuta malinellus Zeller, in Korea

The apple ermine moth, Yponomeuta malinellus Zeller (Lepidoptera: Yponomeutidae), is a tent caterpillar that feeds on Malus spp. in Korea. Populations of the moth in native areas appeared to be regulated by the assemblage of parasitoids. Phenological associations between host stages and parasitoids, susceptible stage(s) of the host for each parasitoid, and stage‐specific parasitism were studied. The egg larval parasitoid Ageniaspis fuscicollis (Dalman) had highest parasitism of first instar larvae (24%), with 14% parasitism of other larval stages. Dolichogenidea delecta (Haliday) was recovered from all larval instars with the highest parasitism rate of second instar larvae (20.1%), followed by 19.9% parasitism of mid‐larval hosts. Herpestomus brunicornis Gravenhorst was reared from second instar larvae through to pupal collection, and had the highest parasitism rate (29.9%) at the pupal stage. The larval pupal parasitoid Zenillia dolosa (Meigen) was recovered from mid‐larval to pupal stages with the highest parasitism rate (5.5%) occurring in third to fourth instar larvae. The host stages for developing A. fuscicollis completely overlap with those of D. delecta, and with those of H. brunicornis to some degree. A statistically significant negative correlation exists between A. fuscicollis and these dominant parasitoids, indicating competitive interaction within the host.     

Monophyly of Euaesthetinae (Coleoptera: Staphylinidae): phylogenetic evidence from adults and larvae,review of austral genera,and new larval descriptions

Abstract We develop a morphological dataset for the rove beetle subfamily Euaesthetinae comprising 167 morphological characters (135 adult and 32 larval) scored from 30 terminal taxa including 25 ingroup terminals (from subfamilies Euaesthetinae and Steninae) and five outgroups. Four maximum parsimony analyses using different sets of terminals and character sets were run to test the monophyly of (1) Euaesthetinae, (2) Steninae, (3) Euaesthetinae + Steninae, (4) euaesthetine tribes Austroesthetini, Alzadaesthetini, Euaesthetini, Fenderiini and Stenaesthetini, and (5) the ten currently known austral endemic genera together. Analyses of adult and larval character sets separately and in combination recovered the monophyly of Euaesthetinae, Steninae, and both subfamilies together, with strong support. Analysis of 13 ingroup terminals for which complete data were available suggests that monophyly of Euaesthetinae is supported by 19 synapomorphies (13 adult, six larval), of Steninae by 23 synapomorphies (14 adult, nine larval), and of both subfamilies together by 24 synapomorphies (21 adult, three larval). Within Euaesthetinae, only the tribe Stenaesthetini was recovered as monophyletic based on adult characters, and in no analyses were the ten austral endemic genera recovered as a monophyletic group. Phylogenetic relationships among euaesthetine genera were weakly supported, although analyses including adult characters supported monophyly of Octavius and Protopristus separately, and of Octavius + Protopristus, Austroesthetus + Chilioesthetus and Edaphus + Euaesthetus. Steninae may include a third genus comprising two undescribed species probably possessing a ‘stick–capture’ method of prey capture, similar to that in Stenus. These two species formed a strongly supported clade recovered as the sister group of Stenus based on adult characters. Diagnoses and a key to adults are provided for the 15 euaesthetine genera currently known from the austral region (Australia, New Zealand, South Africa and southern South America). Euaesthetine larvae previously were known only for Euaesthetus, and we describe the larvae of nine more genera and provide the first larval identification key for genera of Euaesthetinae.     

Early Developmental Stages of the Green Tiger Prawn, Penaeus semisulcatus de Haan (Crustacea, Decapoda, Penaeidae)

Gravid females of Penaeus semisulcatus were spawned in the laboratory by natural means. The embryos were documented and the larvae were reared from hatching to postlarval stage at 28.2–30.0 °C and 33.5–34.5 g kg⁻¹ salinity for about 10 days (223 h 55 min). Six naupliar stages, three protozoea stages, three mysis stages and the first postlarval stage were described and illustrated. The larvae were fed only with microalgae Tetraselmis tetrathele and Chaetoceros gracilis from first protozoea until the second mysis, with about 90% survival rate; from the third mysis until the first postlarva they were fed with similar microalgae coupled with rotifer Brachionus plicatilis and Artemia nauplii. The embryonic and larval stages of P. semisulcatus are generally similar to those of other closely related species in the family Penaeidae, such as Melicertus canaliculatus, Fenneropenaeus merguiensis, and Marsupenaeus japonicus, except for the size and structure of diagnostic characters, setation of appendages and duration of metamorphoses. The change in the feeding habit during ontogeny was related to morphological transformation of the feeding apparatus of larvae and postlarvae. This paper is the first comprehensive and complete account of the early developmental stages of P. semisulcatus.     

Comparative morphology,biology and phylogeny of terminal‐instar larvae of the European species of Toryminae (Hym., Chalcidoidea,Torymidae) parasitoids of gall wasps (Hym. Cynipidae)

We present a phylogenetic and taxonomic study of the morphology and biology of the terminal‐instar larval stage of 19 species representing all the genera of Torymidae parasitoids of gall wasps in Europe, with the single exception of Megastigmus. The genera studied include Adontomerus Nikol'skaya, Idiomacromerus Crawford, Chalcimerus Steffan & Andriescu, Glyphomerus Förster, Pseudotorymus Masi and Torymus Dalman. We primarily used chaetotaxy and some head structures. The terminal‐instar larvae of all studied species are thoroughly described for the first time and illustrated with SEM images. We provide diagnostic characters for the family and the genera studied, and keys to genera and species for the identification of torymid larvae associated with cynipid galls. The majority of the torymid larvae studied are solitary monophagous parasitoids. Finally, to assess the potential use of larval characters in systematic studies of the family, a phylogenetic analysis of the studied taxa based on 42 larval morphological characters is proposed and compared with the current taxonomy of Torymidae. Our results suggest that body chaetotaxy, and characters of the head and mouthparts could be used for genera and species discrimination. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 676–721.     

Larval stages of the deep-sea lobster Polycheles typhlops (Decapoda,Polychelida) identified by DNA analysis: morphology,systematic, distribution and ecology

A total of 25 specimens of Eryoneicus larvae were collected near the Balearic Archipelago (Western Mediterranean Sea) in 2009 and 2010. Detailed morphological examination indicated that the smallest individual corresponded with the first zoea (ZI) stage of Polycheles typhlops hatched from a berried female by Guerao and Abelló (J Nat Hist 30(8):1179–1184, 1996). Only two species of deep-sea polychelid lobster, namely P. typhlops and Stereomastis sculpta, are known to occur in the Mediterranean. Genetic distance comparisons and phylogenetic analysis of the mitochondrial 16S rDNA and Cox I genes of this early larva together with adults from several Polycheles and Stereomastis species allowed us to assign it to P. typhlops. This is the first wild-caught larval stage of a polychelid lobster being identified using molecular techniques. The remaining specimens were attributed to zoeal stages II–III and decapodid stage based on morphological comparison. The arrangement of spines along the anterior part of the middorsal line (R, 1, 1, 1, 2, C₁), characteristic of the former species E. puritanii, discriminates these larvae from other Eryoneicus found in the Mediterranean. The clear presence of epipods on the third maxilliped and pereiopods of the decapodid stage gives further support to the identification of E. puritanii as the larval stages of P. typhlops. Additionally, information on the ecology of these larvae, their abundances during different seasons, as well as their bathymetric distribution is reported.     

Phylogeny of Berosini (Coleoptera: Hydrophilidae,Hydrophilinae) based on larval and adult characters,and evolutionary scenarios related to habitat shift in larvae

Abstract A phylogenetic analysis of Berosini including 15 taxa, 11 of them belonging to Berosini (ingroup), was performed. Of the 58 characters used, 32 derive from the larval stages, and 26 from the adult stage. Two well‐supported clades are recognized, one comprising Hemiosus and Berosus, and the other comprising Derallus, Regimbartia and Allocotocerus. Several larval evolutionary trends are discussed: shifts to benthic and cryptic habits, morphological modifications and adaptations related to these habits, and morphological changes of the clypeolabrum and head appendages. A comparative table for the larval stages of the five genera is included.     

Molecular and morphological comparison of larvae and juveniles of five species of callionymids,with ontogenetic evidence on the monophyly of Repomucenus (Callionymidae)

Dragonet fishes (Callionymidae) are benthic inhabitants of shallow waters, even in tidal pools, down to depths below 900 m in all subtropical, tropical and temperate oceans. The family comprises 200 species in 20 genera worldwide, of which 18 species in 6 genera occur in Korea. Classification within the family Callionymidae has been controversial because of the differing proposals of Fricke and Nakabo (Fishes of Japan with pictorial keys to the species, 1983). For example, Fricke suggested genus Repomucenus and Bathycallionymus, whose genera contains most callionymid species in Korean waters, as junior synonym of genus Callionymus while Nakabo (Fishes of Japan with pictorial keys to the species, 1983) suggested as valid. In such cases, when classifications of adults have taxonomic contention, examination of larval characters may prove informative. Therefore, in this study, the authors conducted comprehensive molecular and morphological analyses on larvae and juveniles of five species in the genus Repomucenus and discussed their taxonomic status within the family Callionymidae. Larval and juvenile callionymids show high morphological similarities during their ontogenetic development. Nonetheless, the following morphological differences were observed in melanophore distribution and preopercular spine development: (a) stellate or punctate melanophores in Bathycallionymus kaianus vs. branched melanophores in genus Repomucenus, (b) melanophores on the abdominal cavity gradually disappearing in B. kaianus vs. gradually becoming prominent in Repomucenus and (c) preopercular spine development giving rise to one perpendicular spine in B. kaianus vs. two or three spines in Repomucenus. Molecular analysis based on 16S ribosomal RNA showed similar results to the morphological analysis. Genera Bathycallionymus and Repomucenus showed significant genetic distance (d = 0.113–0.120); moreover, genus Callionymus, which was suggested as a senior synonym of genus Bathycallionymus and Repomucenus by Fricke (Journal of Natural History, 2014, 48, 2419–2448), also showed considerable difference (d = 0.226–0.246). In the present study, the monophyly of genus Repomucenus seemed well supported by the results of morphological and molecular analyses of larval stage Callionymidae.     

A new genus of mantidflies discovered in the Oriental region,with a higher‐level phylogeny of Mantispidae (Neuroptera) using DNA sequences and morphology

A remarkable new genus and two new species of Mantispidae (Neuroptera) are described from the Oriental region. Allomantispa Liu, Wu, Winterton & Ohl gen.n. , currently including A. tibetana Liu, Wu & Winterton sp.n. and A. mirimaculata Liu & Ohl sp.n. The new genus is placed in the subfamily Drepanicinae based on a series of morphological characteristics and on the results of total evidence phylogenetic analyses. Bayesian and Parsimony analyses were undertaken using three gene loci (CAD, 16S rDNA and COI) combined with 74 morphological characters from living and fossil exemplars of Mantispidae (17 genera), Rhachiberothidae (two genera) and Berothidae (five genera), with outgroup taxa from Dilaridae and Osmylidae. The resultant phylogeny presented here recovered a monophyletic Mantispidae with ?Mesomantispinae sister to the rest of the family. Relationships among Mantispidae, Rhachiberothidae and Berothidae support Rhachiberothidae as a separate family sister to Mantispidae. Within Mantispidae, Drepanicinae are a monophyletic clade sister to Calomantispinae and Mantispinae. In a combined analysis, Allomantispa gen.n. was recovered in a clade comprising Ditaxis McLachlan from Australia, and two fossil genera from the Palaearctic, ?Promantispa Panfilov (Kazakhstan; late Jurassic) and ?Liassochrysa Ansorge & Schlüter (Germany; Jurassic), suggesting a highly disjunct and relictual distribution for the family. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:464B06E8‐47E6‐482E‐8136‐83FE3B2E9D6B .     

Influence of lecithotrofic feeding on growth and development of larvae of freshwater prawn <Emphasis Type="Italic">Macrobrachium rosenbergii</Emphasis>

In the giant freshwater prawn Macrobrachium rosenbergii (De Man), lecithotrofic feeding was discovered at the zoea I stage, and facultative lecithotrofic feeding was found at the zoea II stage. Cases of the completion of the first two stages without feeding were detected. However, a delay in feeding at the zoea II stage caused the inhibition of the growth and development of larvae. In this connection, we recommend to introduce food to the aquaculture of the giant freshwater prawn on the end of the first day after hatching, when the first zoea II larvae emerge.     

Interaction of Acronicta rumicis (Lepidoptera: Noctuidae) and its larval parasitoid, Glyptapanteles liparidis (Hymenoptera: Ichneumonidae)

As a result of parasitism by Glyptapanteles liparidis in the first, second, third and fourth instar larvae of Acronicta rumicis, the mortality of each larval stage was found to be 46.67, 90, 71 and 16.67%, respectively. The mortality was highest when G. liparidis parasitized the second and third instar larvae. The difference in mortality between the parasitized group and the control group was 72.14% in the second instar larvae. With regards to the food consumption of the parasitized larvae, the first and second instar larvae consumed 6495.58 ± 646.52 mm² (leaf surface) and 7951.12 ± 4167.36 mm², respectively, while the third and fourth larvae consumed 13 826.77 ± 3396.66 mm² and 18 599.85 mm², respectively, showing that food consumption increased with instar stages of the host larvae. The clutch size of G. liparidis increased in relation to the instar stages of the host: it was 25.25 ± 7.89, 48.65 ± 53.75, 91.09 ± 44.52 and 114 individuals when they were fed with the first, second, third and the fourth instar larvae of the host, respectively.     

Modelling developmental changes in the carbon and nitrogen budgets of larval brachyuran crabs

The uptake and partitioning of nutritional carbon (C) and nitrogen (N) were studied during the complete larval development of a brachyuran crab,Hyas araneus, reared under constant conditions in the laboratory. Biochemical and physiological data were published in a foregoing paper, and complete budgets of C and N were now constructed from these data. Regression equations describing rates of feeding (F), growth (G), respiration (R), and ammonia excretion (U) as functions of time during individual larval moult cycles were inserted in a simulation model, in order to analyse time-dependent (i.e. developmental) patterns of variation in these parameters as well as in bioenergetic efficiencies. Absolute daily feeding rates (F; per individual) as well as carbon and nitrogen-specific rates (F/C, F/N) are in general maximum in early, and minimum in late stages of individual larval moult cycles (postmoult and premoult, respectively). Early crab zoeae may ingest equivalents of up to ca 40% body C and 30% body N per day, respectively, whereas megalopa larvae usually eat less than 10%. Also growth rates (G; G/C, G/N) reveal decreasing tendencies both during individual moult cycles and, on the average, in subsequent instars. Conversion of C and N data to lipid and protein, respectively, suggests that in all larval instars there is initially an increase in the lipid: protein ratio. Protein, however, remains clearly the predominant biochemical constituent in larval biomass. The absolute and specific values of respiration (R; R/C) and excretion (U; U/N) vary only little during the course of individual moult cycles. Thus, their significance in relation toG increases within the C and N budgets, and net growth efficiency (K ₂) decreases concurrently. Also gross growth and assimilation efficiency (K ₂; A/F) are, in general, maximum in early stages of the moult cycle (postmoult). Biochemical data suggest that lipid utilization efficiency is particularly high in early moult cycle stages, whereas protein utilization efficiency is higher in later stages. Only the zoea II appears to accumulate lipid from food constantly with a higher conversion efficiency than protein. The cumulative C and N budgets show in subsequent larval instars conspicuously increasing figures in all of their parameters.F andG increase to a particularly high extent from the first to the second zoeal instar, whereasR, U, exuvia production (G _E), and total assimilation (A) reveal a greater increase from the zoea II to the megalopa. Respiratory, excretory, and exuvial losses increase in subsequent larval instars at higher rates than tissue growth and, hence,K ₂ decreases in the same order. In the C budget,K ₂ values of 0.63 (zoea I). 0.56 (zoea II), and 0.29 (megalopa) were calculated (or: 0.56, 0.46, and 0.16 after subtraction of exuviae). In the N budget, corresponding values of 0.76, 0.66, and 0.45 (or: 0.72, 0.62, 0.38 without exuviae) were obtained. AlsoK ₁ decreases slightly in subsequent instars, whereasA/F reveals rather an increasing tendency, at least from the zoeal instars to the megalopa. Changes in the uptake and partitioning of matter in crab larvae are discussed in relation to developmental events and changes in life style before metamorphosis.     

Complete larval and early juvenile development of the mangrove crab Perisesarma fasciatum (Crustacea: Brachyura: Sesarmidae) from Singapore, with a larval comparison of Parasesarma and Perisesarma

The complete larval development of the sesarmid crab Perisesarmafasciatum (Lanchester, 1900) from Singapore was obtained fromlaboratory culture. All four zoeal stages, the megalopa andthe first crab stage are described and illustrated. The morphologicalcharacteristics of the larvae of P. fasciatum are compared withthose of other known larvae of the genera Perisesarma and Parasesarma.The larval morphology of P. fasciatum clearly presents the typicalcombination of features that characterize sesarmid larvae. Overall,larval stages are very similar in Perisesarma and Parasesarmaand it is impossible to distinguish these two genera by larvalmorphology.     

The fauna of the South China Sea include unknown phoronid species: new records of larvae and adults

The Phoronida is a phylum of marine invertebrates that have a worldwide distribution and that form huge benthic aggregations in many aquatic areas. Although there are only 11 recognized species of phoronids, many species clearly remain to be described. The matching of larval and adult stages of the same species will help indicate which larvae belong to described species and which represent undescribed species whose adults have yet to be found. Larvae of four phoronid species were collected in Nha Trang Bay and investigated by light microscopy and molecular methods. Three of the described larvae belong to new phoronid species that have yet to be named. These larvae have unique morphological features and occupy separate positions on the phylogenetic tree of phoronids. One of the described larvae belongs to Phoronis hippocrepia or to a closely related species. Observations made with a new macrophotographic method indicated that Phoronopsis californica also occurs in Nha Trang Bay. Thus, according to records of larvae and adults, Nha Trang Bay contains at least nine phoronid species: Phoronopsis californica, Phoronopsis malakhovi, Phoronis australis, Phoronis hippocrepia (or a closely related species), three unknown phoronid species whose larvae have unique morphological features and that apparently belong to the genus Phoronis, and two species, whose adults have unique set of morphological features. The richness of phoronids in this area suggests that the Indo-Pacific is a centre of phoronid biodiversity.     

Physiological and biochemical changes during the larval development of a brachyuran crab reared under constant conditions in the laboratory

Larvae of the spider crabHyas araneus were reared in the laboratory at constant conditions (12°C; 32‰S), and their feeding rate (F), oxygen consumption (R), nitrogen excretion (U), and growth were measured in regular intervals of time during development from hatching to metamorphosis. Growth was measured as dry weight (W), carbon (C), nitrogen (N), hydrogen (H) protein, and lipid. All these physiological and biochemical traits revealed significant changes both from instar to instar and during individual larval moult cycles. AverageF was low in the zoea I, reached a maximum in the zoea II, and decreased again in the megalopa. In the zoeal instars, it showed a bell-shaped pattern, with a maximum in the middle (zoea I) or during the first half of the moult cycle (zoea II). MaximumF in the megalopa was observed still earlier, during postmoult. Respiration (R) increased in the zoeal instars as a linear function of time, whereas it showed a sinusoidal pattern in the megalopa. These findings on variation inF andR during larval development confirm results obtained in previous studies onH. araneus and other decapod species. Excretion (U) was measured for the first time with a high temporal resolution in crab larvae. It showed in all three larval instars a bell-shaped variation pattern, with a maximum near the middle of the moult cycle, and significantly increasing average values from instar to instar. The atomicO/N ratio followed an inverse pattern, suggesting a maximum utilization of protein as a metabolic substrate during intermoult. Growth data from the present study and from a number of previous studies were compiled, showing consistency of growth patterns, but a considerable degree of variability between larvae from different hatches reared under identical conditions. The data show the following consistent tendencies: during the first part of each larval moult cycle (in postmoult, partly in intermoult), lipids are accumulated at a higher rate than protein, whereas an inverse growth patterns is typical of the later (premoult) stages. These two different growth phases are interpreted as periods dominated by reserve accumulation in the hepatopancreas, and epidermal growth and reconstruction (morphogenesis), respectively. Differences between individual larval instars in average biochemical composition and growth patterns may be related to different strategies: the zoeal instars and the early megalopa are pelagic feeding stages, accumulating energy reserves (principally lipids) necessary for the completion of larval development, whereas the later (premoult) megalopa is a semibenthic settling stage that converts a significant part of this energy to epidermal protein. The megalopa shifts in behaviour and energy partitioning from intense feeding activity and body growth to habitat selection and morphogenesis, preparing itself for metamorphosis, i.e. it shows an increasing degree of lecithotrophy. Data from numerous parallel elemental and biochemical analyses are compiled to show quantitative relationships betweenW, C, N, H, lipid, and protein. These regressions may be used as empirical conversion equations for estimates of single chemical components in larvalHyas araneus, and, possibly, other decapods.