Aspects of the breeding biology of Janaira gracilis Moreira & Pires (Crustacea, Isopoda, Asellota)

The biological aspects of incubating females of Janaira gracilis Mbreira & Pires, are described. The marsupium is formed by 4 pairs of oostegites arising from pereopods I-IV. The oostegites appear for the first time at the post-marsupial stage 7 (preparatory stage 1), growing successively at each moult until stage 9 (brooding stage 1), when they reach fully development. The sizes of the eggs increase with the body size of the females. The number of eggs, per female, is a linear function of the body volume, i.e., the fecundity increases with the female's body size. The number of eggs, embryos and juveniles decrease during the marsupial development. This decrease in brood number is higher between the last two marsupial stages, i.e., from stage C to D, than between the preceding marsupial stages. The average and overall brood mortality rate is of 38.95%.

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The developmental variations of the sagitta otolith in the young and mature male of a hermaphrodite polynemidae fish, Eleutheronema tetradactylum (Shaw, 1804)

Papéis Avulsos de Zoologia ◽

10.11606/1807-0205/2021.61.78 ◽

2021 ◽

Vol 61 ◽

pp. e20216178

Author(s):

Soumen Roy ◽

Itika Bardhan

Keyword(s):

Body Size ◽

Fork Length ◽

The Body ◽

Size Groups ◽

Protandrous Hermaphrodite ◽

Ultrastructural Characteristics ◽

Developmental Variations ◽

The One ◽

First Time ◽

One Way Anova

The Eleutheronema tetradactylum is a protandrous, hermaphrodite, marine perciformes fish. The body length of this fish acts as an important diagnostic marker for male and female discrimination. The present study describes for the first time the ultrastructural characteristics on the medial surface of the sagitta otolith in different body size groups of males of E. tetradactylum (Polynemidae: Perciformes) using scanning electron microscopy. The sagitta is a spindle-shaped structure that includes a well-developed rostrum and a poorly developed antirostrum. The sulcus is ostio-pseudocaudal type, almost straight and devoid of the collum. The ostium is a well-developed, vase-shaped structure. The cauda includes the colliculum and a well-developed caudal bulb with several distinct growth stripes. The length of the caudal bulb is significantly correlated to the growth of the body size of the fish. The excisura major is indistinct and the excisura minor is absent. The cristae are distinct on both sides of the sulcus. The one-way ANOVA test revealed that the development of several sagitta features shows significant differences in various body size groups of E. tetradactylum. The growth of the sagitta length is more closely related to the fork length than the sagitta width. Therefore, the sagitta length and the caudal bulb length can be used as important predictors to evaluate the fish size. The cauda region of the sagitta in E. tetradactylum is unique as well as more decorative than those of another Polynemidae fish and other hermaphrodite, marine perciformes fishes. The sagitta characteristics of E. tetradactylum might be advantageous in the identification of the sex and the taxonomy of the hermaphrodite fish species.

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Description of the male of fossil <i>Calomicrus eocenicus</i> Bukejs et Bezděk (Coleoptera: Chrysomelidae: Galerucinae) from Eocene Baltic amber using X-ray microtomography

Fossil Record ◽

10.5194/fr-23-105-2020 ◽

2020 ◽

Vol 23 (1) ◽

pp. 105-115 ◽

Cited By ~ 1

Author(s):

Andris Bukejs ◽

Jan Bezděk ◽

Vitalii I. Alekseev ◽

Kristaps Kairišs ◽

Ryan C. McKellar

Keyword(s):

Body Size ◽

Body Cavity ◽

The Body ◽

Baltic Amber ◽

Sexually Dimorphic ◽

Apical Margin ◽

Fossil Species ◽

X Ray ◽

Total Body ◽

First Time

Abstract. A male representative of the extinct species Calomicrus eocenicus Bukejs et Bezděk, 2014 (Chrysomelidae: Galerucinae) is found and described for the first time from Eocene Baltic amber using X-ray microtomography. The aedeagus is well preserved within the body cavity of the specimen, and it is illustrated in detail. This fossil species exhibits distinct sexual dimorphism: the male has a smaller total body size, as well as a copula-adapted modification in abdominal ventrite 5 (apical margin deeply trilobed, with round medial fovea present); meanwhile the female is larger in body size and has a simple abdominal ventrite 5 (without fovea, non-incised and widely rounded apically). Similar sexually dimorphic characters are typical for extant members of the tribe Luperini, and this report is the first time that they are described in an Eocene species. The known sexually dimorphic characters present in Coleoptera within Eocene Baltic amber are briefly discussed.

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New species, new records and a checklist of oribatid mites (Acari: Oribatida) from Nepal

Biologia ◽

10.2478/s11756-014-0485-2 ◽

2014 ◽

Vol 69 (12) ◽

Author(s):

Sergey Ermilov ◽

Jochen Martens

Keyword(s):

New Species ◽

Body Size ◽

New Records ◽

Oribatid Mite ◽

The Body ◽

Central Nepal ◽

Two New Species ◽

Size And Morphology ◽

Annotated Checklist ◽

First Time

AbstractAn annotated checklist of identified oribatid mite taxa from Nepal is provided. It includes 77 species/subspecies, 56 genera and 40 families; 36 species/subspecies, 21 genera and nine families are recorded for the first time in Nepal. Two new species, Vilhenabates schawalleri sp. n. (Haplozetidae) and Taiwanoppia (Taiwanoppia) paranepalica sp. n. (Oppiidae), are described from soil of central Nepal. Vilhenabates schawalleri sp. n. is morphologically similar to V. giganteus Ermilov & Rybalov, 2012, however, it differs from the latter by the body size, length of rostral, lamellar and subcapitular setae, location of lamellar setae, adanal setae ad 3 and adanal lyrifissures and number of porose areas. Taiwanoppia (Taiwanoppia) paranepalica sp. n. is morphologically similar to T. (T.) nepalica Ermilov & Martens, 2014, however, it differs from the latter by the body size and morphology of the rostrum.

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The genetic architecture underlying body-size traits plasticity over different temperatures and developmental stages in Caenorhabditis elegans

10.1101/2021.04.21.440777 ◽

2021 ◽

Author(s):

Muhammad I. Maulana ◽

Joost A.G. Riksen ◽

Basten L. Snoek ◽

Jan E. Kammenga ◽

Mark G. Sterken

Keyword(s):

Body Size ◽

Caenorhabditis Elegans ◽

Genetic Architecture ◽

Developmental Stages ◽

Recombinant Inbred Lines ◽

The Body ◽

Body Volume ◽

Chromosome X ◽

Different Temperatures ◽

Length Width

Most ectotherms obey the temperature-size rule, meaning they grow larger in a colder environment. This raises the question of how the interplay between genes and temperature affect the body size of ectotherms. Despite the growing body of literature on the physiological life-history and molecular genetic mechanism underlying the temperature-size rule, the overall genetic architecture orchestrating this complex phenotype is not yet fully understood. One approach to identify genetic regulators of complex phenotypes is Quantitative Trait Locus (QTL) mapping. Here, we explore the genetic architecture of body size phenotypes, in different temperatures using Caenorhabditis elegans as a model ectotherm. We used 40 recombinant inbred lines (RILs) derived from N2 and CB4856, which were reared at four different temperatures (16oC, 20oC, 24oC, and 26oC) and measured at two developmental stages (L4 and adult). The animals were measured for body length, width at vulva, body volume, length/width ratio, and seven other body-size traits. The genetically diverse RILs varied in their body-size phenotypes with heritabilities ranging from 0.0 to 0.99. We detected 18 QTL underlying the body-size phenotypes across all treatment combinations, with the majority clustering on chromosome X. We hypothesize that the chromosome X QTL could result from a known pleiotropic regulator - npr-1 - known to affect the body size of C. elegans through behavioural changes. In conclusion, our findings shed more light on multiple loci affecting body size plasticity and allow for a more refined analysis of the temperature-size rule.

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Appraising Behaviour During Male-male Interaction in the Japanese Horned Beetle Trypoxylus Dichotomus Septentrionalis (Kono)

Behaviour ◽

10.1163/156853903322127959 ◽

2003 ◽

Vol 140 (4) ◽

pp. 501-517 ◽

Cited By ~ 63

Author(s):

Yoshihito Hongo

Keyword(s):

Body Size ◽

The Body ◽

The Other ◽

Size Difference ◽

Horn Length ◽

Horned Beetle ◽

The Difference ◽

Contest Behaviour ◽

Trypoxylus Dichotomus ◽

Stage 1

AbstractDetailed contest behaviour of the Japanese horned beetle, Trypoxylus dichotomus septentrionalis, was examined in the field. Male-male interactions have three sequences, and in these sequences four behavioural stages were recognized. After two males encountered (Stage 1), they always faced and shoved each other with their horns (Stage 2: 'Shoving'). Then, if the horn length or body size difference between the contestants was large, one male began to retreat and was chased by the other male, and the interactions terminated (Stage 4A: 'Chasing'). If the difference was small, the interactions proceeded to the escalated fighting stage (Stage 3: 'Pry'), in which two males put their horns under their opponents and push and try to flip them up each other. The interactions, which proceeded to Stage 3, have two ways of termination. If the body size difference was large, one male was flipped up by the other male, and the interactions was terminated quickly (Stage 4B). If the difference was small, the interactions was not terminated so quickly and continued until one male began to retreat, proceeding to Stage 4A. It is suggested that males with shorter horns relative to the opponents avoid the escalated fighting stage, 'Pry', after perceiving the horn length difference during 'Shoving', which would be an appraising behaviour. Thus, 'Shoving' is the most important stage among all the interaction processes in that the highest proportion of judgement is made here. The great allometric variation of horn length would presently function more greatly for enhancing the efficiency of mutual appraisal than that in actual fighting.

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Taxonomic study of Setoxylobates (Acari, Oribatida, Haplozetidae) and some related taxa

Systematic and Applied Acarology ◽

10.11158/saa.25.8.13 ◽

2020 ◽

Vol 25 (8) ◽

pp. 1516-1525

Author(s):

Sergey G. Ermilov ◽

Jhih-Rong Liao

Keyword(s):

New Species ◽

Body Size ◽

Taxonomic Status ◽

The Body ◽

Generic Diagnosis ◽

Taxonomic Study ◽

Generic Status ◽

First Time ◽

One New Species ◽

A New Species

The genus Setoxylobates (Oribatida, Haplozetidae) is recorded in Taiwan for the first time; one new species of this genus is described based on adults from soil of mountain tea farm in Taiwan. Setoxylobates taigangensis Ermilov sp. nov. differs from Setoxylobates foveolatus Balogh & Mahunka, 1967 in having smaller body size and setiform bothridial setae, and the absence of foveolae on the body. Revised generic diagnosis and an identification key to known species of Setoxylobates are provided. The taxonomic status and systematic placement of some related poronotic taxa are discussed, resulting in the following new taxonomic proposals: Protoribates Berlese, 1908 (=Lignobates Mahunka, 2006 syn. nov.); Setoxylobates Balogh & Mahunka, 1967 (=Plenoxylobates Hammer, 1979 syn. nov.). A new species name is proposed: Protoribates mahunkasandori Ermilov nom. nov. (=Lignobates berndhauseri Mahunka, 2006, preoccupied by Mahunka 1993). The initial generic status of Polyxylobates Hammer, 1973 and the position of Perxylobates mayuloeus Corpuz-Raros, 1979 in Perxylobates are supported.

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Larger is Better in the Parasitoid Eretmocerus warrae (Hymenoptera: Aphelinidae)

Insects ◽

10.3390/insects11010039 ◽

2020 ◽

Vol 11 (1) ◽

pp. 39

Author(s):

Tao Wang ◽

Michael A. Keller

Keyword(s):

Body Size ◽

Developmental Stages ◽

Adult Stage ◽

Life Time ◽

Trialeurodes Vaporariorum ◽

The Body ◽

Adult Longevity ◽

Body Volume ◽

Greenhouse Whitefly ◽

Body Sizes

Eretmocerus warrae (Hymenoptera: Aphelinidae) is a specialist parasitoid that is used for the control of the greenhouse whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae). We investigated how temperature affects the body-size, life-time oviposition, and longevity of E. warrae at different stages of life. The body-sizes of both this parasitoid and its host are influenced by temperature. Body-volume indices that reflect body-sizes fell by 47.7 % in T. vaporariorum compared with 57.6% in E. warrae when temperature increased from 20 to 32 °C. The life-time oviposition of female adults of E. warrae that grew at the immature developmental temperature of 20 °C was 86 ± 22 eggs, more than 66 ± 11 eggs at 26 °C, and 65 ± 23 eggs at 32 °C. Besides the influence on fecundity, temperature also influences the oviposition behaviour at the adult stage. More eggs were oviposited at 20 and 26 °C than at 32 °C. Higher temperatures reduced survival in the immature developmental stages and longevity in adults. Adult females lived for a maximum of 8.9 ± 1.8 days at 20 °C and laid a maximum of 97.4 ± 23.2 eggs when reared at 20 °C and maintained at 26 °C as adults. Adult body-size is positively correlated with life-time oviposition but not adult longevity. The results imply that temperature influences the nature of interactions between a parasitoid and its host. Larger wasps can live longer and parasitise more hosts, which should improve their performance as biological control agents.

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The postcranial skeleton of the erythrosuchid archosauriform Garjainia prima from the Early Triassic of European Russia

Royal Society Open Science ◽

10.1098/rsos.201089 ◽

2020 ◽

Vol 7 (12) ◽

pp. 201089

Author(s):

Susannah C. R. Maidment ◽

Andrey G. Sennikov ◽

Martín D. Ezcurra ◽

Emma M. Dunne ◽

David J. Gower ◽

...

Keyword(s):

Body Size ◽

Mass Extinction ◽

Middle Triassic ◽

Large Body ◽

The Body ◽

European Russia ◽

Early Triassic ◽

Postcranial Skeleton ◽

Large Body Size ◽

First Time

Erythrosuchidae were large-bodied, quadrupedal, predatory archosauriforms that dominated the hypercarnivorous niche in the aftermath of the Permo-Triassic mass extinction. Garjainia , one of the oldest members of the clade, is known from the late Olenekian of European Russia. The holotype of Garjainia prima comprises a well-preserved skull, but highly incomplete postcranium. Recent taxonomic reappraisal demonstrates that material from a bone bed found close to the type locality, previously referred to as ‘ Vjushkovia triplicostata ', is referable to G. prima. At least, seven individuals comprising cranial remains and virtually the entire postcranium are represented, and we describe this material in detail for the first time. An updated phylogenetic analysis confirms previous results that a monophyletic Garjainia is the sister taxon to a clade containing Erythrosuchus, Shansisuchus and Chalishevia . Muscle scars on many limb elements are clear, allowing reconstruction of the proximal locomotor musculature. We calculate the body mass of G. prima to have been 147–248 kg, similar to that of an adult male lion. Large body size in erythrosuchids may have been attained as part of a trend of increasing body size after the Permo-Triassic mass extinction and allowed erythrosuchids to become the dominant carnivores of the Early and Middle Triassic.

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Crypsis via leg clustering: twig masquerading in a spider

Royal Society Open Science ◽

10.1098/rsos.150007 ◽

2015 ◽

Vol 2 (3) ◽

pp. 150007 ◽

Cited By ~ 5

Author(s):

Shichang Zhang ◽

Kuei-Kai Mao ◽

Po-Ting Lin ◽

Chiu-Ju Ho ◽

Wei Hung ◽

...

Keyword(s):

Body Size ◽

Empirical Evidence ◽

Body Length ◽

Predator Avoidance ◽

The Body ◽

Background Matching ◽

First Time

The role of background matching in camouflage has been extensively studied. However, contour modification has received far less attention, especially in twig-mimicking species. Here, we studied this deceptive strategy by revealing a special masquerade tactic, in which the animals protract and cluster their legs linearly in the same axis with their bodies when resting, using the spider Ariamnes cylindrogaster as a model. We used cardboard papers to construct dummies resembling spiders in appearance and colour. To differentiate the most important factors in the concealment effect, we manipulated body size (long or short abdomen) and resting postures (leg clustered or spread) of the dummies and recorded the responses of predators to different dummy types in the field. The results showed that dummies with clustered legs received significantly less attention from predators, regardless of the body length. Thus, we conclude that A. cylindrogaster relies on the resting posture rather than body size for predator avoidance. This study provides, to the best of our knowledge, empirical evidence for the first time that twig-mimicking species can achieve effective camouflage by contour modification.

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Contribution to the knowledge of oribatid mites of Colombia, with description of two new species of Galumna (Acari, Oribatida, Galumnidae)

Systematic and Applied Acarology ◽

10.11158/saa.22.1.11 ◽

2017 ◽

Vol 22 (1) ◽

pp. 102

Author(s):

Sergey G. Ermilov

Keyword(s):

New Species ◽

Body Size ◽

Oribatid Mite ◽

Oribatid Mites ◽

The Body ◽

Two New Species ◽

First Time

The present study is based on oribatid mite material collected in 1937 in Colombia. A list of identified taxa, including 13 species from 11 genera and 10 families is presented; of these, two species of the genus Galumna are new to science, 10 species, 10 genera and eight families are recorded in this country for the first time. Galumna (Galumna) colombiana sp. nov. differs from to G. (Galumna) innexa Pérez-Íñigo & Baggio, 1986 by the sculpture of prodorsum, ornamentation of pteromorphs, morphology of bothridial heads, length of rostral and lamellar setae and localization of notogastral lyrifissures im. Galumna (Galumna) naturalisi sp. nov. differs from G. (Galumna) reticulata Hammer, 1958 by the body size, sculpture of prodorsum and the development of lenticulus.

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