External changes in embryonic and larval development of Odontophrynus cordobae Martino et Sinsch, 2002 (Anura: Cycloramphidae)

Biologia ◽  
2011 ◽  
Vol 66 (6) ◽  
Author(s):  
Pablo Grenat ◽  
Lucio Zavala Gallo ◽  
Nancy Salas ◽  
Adolfo Martino
Keyword(s):  
Larval Development ◽  
Body Mass ◽  
Related Species ◽  
Developmental Stages ◽  
Morphological Changes ◽  
Larval Form ◽  
Larval Stages ◽  
In Captivity ◽  
Mass Increment ◽  
Embryonic And Larval Development

AbstractWe provide the first description of development for a species belonging to Odontophrynus genus by describing all external changes of embryonic and larval stages for Odontophrynus cordobae. External morphological changes through development were analyzed on specimens bred in captivity. Embryonic and larval development, from fertilization to metamorphosis, was completed in 62 days and 46 stages were defined. We split the staging series into ten developmental groups: fertilization (stages 1 and 2); segmentation (stages 3–9); gastrulation (stages 10–12); neurulation (stages 13–16); elongation (stages 17–19); external gill larva (stages 20–24); internal gill larva (stage 25); pre-metamorphosis (stages 26–41); pro-metamorphosis (stage 42); metamorphic climax (stages 43–46). Marked increases in total length were evidenced during elongation and during stage 25, when the tadpole begins to feed. Stage 25 was the longest one (8 days) and it was related to organs rearrangement, morphological progression and body mass increment typical of free life larval form. Similar studies on related species are needed to compare different developmental stages at different taxonomic levels.

Characterization and expression patterns of wnt4 in Exopalaemon carinicauda (Holthuis, 1950) (Caridea, Palaemonidae) during embryonic and larval development

Crustaceana ◽  
2019 ◽  
Vol 92 (1) ◽  
pp. 83-94
Author(s):  
Jian Hua Chen ◽  
Meng Jie Wang ◽  
Xue Li ◽  
Hai Hua Wang ◽  
Huan Gao ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Larval Development ◽  
Developmental Stages ◽  
Integration Site ◽  
Expression Patterns ◽  
Exopalaemon Carinicauda ◽  
Cell Stage ◽  
Larval Stages ◽  
Cell Proliferation And Differentiation ◽  
Embryonic And Larval Development

Abstract Wnt4 (Wingless-type MMTV integration site family member 4) has been demonstrated to play critical roles in a wide variety of biological processes, including embryonic development, cell proliferation, and differentiation in vertebrates, but its function in crustaceans is still not clear. In the present study, the full-length wnt4 cDNA sequence was cloned and characterized for the ridgetail white prawn Exopalaemon carinicauda. The expression patterns of the wnt4 mRNA in embryos and larvae at different stages were investigated. The tissue distribution showed that wnt4 was obviously expressed in eyestalk and hepatopancreas. During embryonic development, the wnt4 was highly expressed in all developmental stages except the zygote, two-cell stage, and late zoaea stage. The wnt4 mRNA was expressed in Z1-Z5 and post-larval stages. Taken together, the present study indicates that the wnt4 gene may be involved in the regulation of embryonic and larval development in the ridgetail white prawn.

Neurogenesis in the thoracic neuromeres of two crustaceans with different types of metamorphic development

1998 ◽  
Vol 201 (17) ◽  
pp. 2465-2479 ◽  
Author(s):  
S Harzsch ◽  
J Miller ◽  
J Benton ◽  
RR Dawirs ◽  
B Beltz
Keyword(s):  
Embryonic Development ◽  
Larval Development ◽  
Neuronal Development ◽  
Temporal Patterns ◽  
Homarus Americanus ◽  
Spider Crab ◽  
Larval Life ◽  
Larval Stages ◽  
Metamorphic Development ◽  
Embryonic And Larval Development

The mode of embryonic and larval development and the ethology of metamorphosis in the spider crab and the American lobster are very different, and we took advantage of this to compare neuronal development in the two species. The goals of this study were to discover whether the differences in the maturation of the neuromuscular system in the pereopods and the metamorphic changes of motor behavior between the two species are reflected at the level of the developing nervous system ('neurometamorphosis'). Furthermore, we wanted to broaden our understanding of the mechanisms that govern neuronal development in arthropods. Proliferation of neuronal stem cells in thoracic neuromeres 4-8 of the lobster Homarus americanus and the crab Hyas araneus was monitored over the course of embryonic and larval development using the in vivo incorporation of bromodeoxyuridine (BrdU). Neuropil structure was visualized using an antibody against Drosophila synapsin. While proliferation of neuronal precursors has ceased when embryogenesis is 80 % complete (E80%) in the lobster thoracic neuromeres, proliferation of neuroblasts in the crab persists throughout embryonic development and into larval life. The divergent temporal patterns of neurogenesis in the two crustacean species can be correlated with differences in larval life style and in the degree of maturation of the thoracic legs during metamorphic development. Several unusual aspects of neurogenesis reported here distinguish these crustaceans from other arthropods. Lobsters apparently lack a postembryonic period of proliferation in the thoracic neuromeres despite the metamorphic remodeling that takes place in the larval stages. In contrast, an increase in mitotic activity towards the end of embryonic development is found in crabs, and neuroblast proliferation persists throughout the process of hatching into the larval stages. In both E20% lobster embryos and mid-embryonic crabs, expression of engrailed was found in a corresponding set of neurons and putative glial cells at the posterior neuromere border, suggesting that these cells have acquired similar specific identities and might, therefore, be homologous. None of the BrdU-labeled neuroblasts (typically 6-8 per hemineuromere over a long period of embryogenesis) was positive for engrailed at this and subsequent stages. Our findings are discussed in relation to the spatial and temporal patterns of neurogenesis in insects.

scholarly journals Phenylalanine Hydroxylase RNAi Knockdown Negatively Affects Larval Development, Molting and Swimming Performance of Salmon Lice

2020 ◽  
Vol 7 ◽  
Author(s):  
Prashanna Guragain ◽  
Bjørnar Sporsheim ◽  
Astrid Skjesol ◽  
Anna Solvang Båtnes ◽  
Yngvar Olsen ◽  
...  
Keyword(s):  
Larval Development ◽  
Developmental Stages ◽  
Phenylalanine Hydroxylase ◽  
Swimming Performance ◽  
Expression Patterns ◽  
Fish Farming ◽  
Economic Losses ◽  
Larval Stages ◽  
Salmon Lice ◽  
Morphological Defects

Phenylalanine hydroxylase (PAH) is a crucial enzyme involved in tyrosine biosynthesis, having roles in neurological and physiological processes. The purpose of PAH has received little attention in crustaceans despite extensive investigations in other arthropods. Here, we characterize the PAH gene for the first time in the parasite Lepeophtheirus salmonis, a copepod that is responsible for huge economic losses in salmonid fish farming. Phylogenetic and sequence analyses confirmed that LsPAH is closely related to the metazoan PAH with conserved ACT regulatory and catalytic domains. Temporal expression patterns revealed that LsPAH is expressed throughout all developmental stages peaking during the copepodite stages, suggesting an essential role in developmental physiology. We used RNAi to knockdown LsPAH expression in the nauplius I stage to study developmental function during the larval stages. PAH knockdown impaired larval development, molting and swimming ability with severe morphological defects. This study provides insight into the role of PAH in copepods and demonstrates the importance of this metabolic gene in salmon louse growth and development.

Swimming speeds of the larval stages of the parasitic barnacle, Heterosaccus lunatus (Crustacea: Cirripedia: Rhizocephala)

2004 ◽  
Vol 84 (4) ◽  
pp. 737-742 ◽  
Author(s):  
Graham Walker
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscope ◽  
Developmental Stages ◽  
Larval Form ◽  
Larval Stages ◽  
Moreton Bay ◽  
Portunid Crab ◽  
Lecithotrophic Development ◽  
Scanning Electron

Heterosaccus lunatus parasitizes the portunid crab, Charybdis callianassa, in Moreton Bay, Queensland, Australia. Larval broods, released during July and August (males only), were allowed to develop through to cyprids (lecithotrophic development). Speeds of all the developmental stages—nauplius I to nauplius IV and the cyprids were measured by timing continuously swimming larvae over 5 mm distances under a microscope. The absolute speeds of the naupliar stages were similar (3–4 mm s−1), but the cyprids were significantly faster at ≈10 mm s−1. These speeds were compared with published speeds of cirripede and copepod nauplii and other cirripede cyprids. Relative speeds (body lengths s−1) showed surprising parity, which for the cyprids probably reflects the similar efficiency of the fusiform shape and thoracopod propulsion for all sizes of this highly specialized larval form. The lecithotrophic H. lunatus nauplii have rather minimalistic appendages (compared with planktotrophic nauplii) which were examined at the light microscope and scanning electron microscope levels. The natatory setae were found to be plumo-denticulate.

Induced Ovulation, Embryonic and Larval Development of Malaysian Mahseer, Tor tambroides (Bleeker, 1854) in Captivity

2013 ◽  
Vol 8 (6) ◽  
pp. 761-774 ◽  
Author(s):  
N.M. Azuadi ◽  
S.S. Siraj ◽  
S.K. Daud ◽  
A. Christianu ◽  
S.A. Harmin ◽  
...  
Keyword(s):  
Larval Development ◽  
Induced Ovulation ◽  
In Captivity ◽  
Embryonic And Larval Development

scholarly journals Embryonic development and larval stages of Steindachneridion parahybae (Siluriformes: Pimelodidae): implications for the conservation and rearing of this endangered Neotropical species

2012 ◽  
Vol 10 (2) ◽  
pp. 313-327 ◽  
Author(s):  
Renato M. Honji ◽  
Carlos E. Tolussi ◽  
Paulo H. Mello ◽  
Danilo Caneppele ◽  
Renata G. Moreira
Keyword(s):  
Larval Development ◽  
Average Length ◽  
Larval Growth ◽  
Average Diameter ◽  
Larval Phase ◽  
Larval Stages ◽  
Neotropical Species ◽  
First Feeding ◽  
In Captivity ◽  
Optic Vesicles

Steindachneridion parahybae is a freshwater catfish endemic to the Paraíba do Sul River and is classified as an endangered Neotropical species. An increasing number of conservation biologists are incorporating morphological and physiological research data to help conservation managers in rescue these endangered species. This study investigated the embryonic and larval development of S. parahybae in captivity, with emphasis in major events during the ontogeny of S. parahybae. Broodstocks were artificially induced to reproduce, and the extrusion occurred 200-255 degree-hours after hormonal induction at 24°C. Larval ontogeny was evaluated every 10 minutes under microscopic/stereomicroscopic using fresh eggs samples. The main embryogenic development stages were identified: zygote, cleavage, including the morula, blastula, gastrula phase, organogenesis, and hatching. The extruded oocytes showed an average diameter of 1.10 ± 0.10 mm, and after fertilization and hydration of eggs, the average diameter of eggs increased to about 1.90 ± 0.60 mm, characterized by a large perivitelline space that persisted up to embryo development, the double chorion, and the poles (animal and vegetative). Cell division started about 2 minutes after fertilization (AF), resulting in 2, 4, 8 (4 x 2 arrangement of cells), 16 (4 x 4), 32 (4 x 8) and 64 (2 x 4 x 8) cells. Furthermore, the blastula and gastrula stages followed after these cells divisions. The closed blastopore occurred at 11 h 20 min AF; following the development, the organogenetic stages were identified and subdivided respectively in: early segmentation phase and late segmentation phase. In the early segmentation phase, there was the establishment of the embryonic axis, and it was possible to distinguish between the cephalic and caudal regions; somites, and the optic vesicles developed about 20 h AF. Total hatching occurred at 54 h AF, and the larvae average length was 4.30 ± 0.70 mm. Gradual yolk sac reduction was observed during the first two days of larval development. The first feeding occurred at the end of the second day. During the larval phase, cannibalism, heterogeneous larval growth and photophobia were also observed. This information will be important in improving the artificial reproduction protocols of S. parahybae in controlled breeding programs.

Description of the ontogenic and larval period of discus fish (Symphysodon aequifasciatus)

Zygote ◽  
2014 ◽  
Vol 23 (3) ◽  
pp. 460-466 ◽  
Author(s):  
Douglas da Cruz Mattos ◽  
Leonardo Demier Cardoso ◽  
Paulo José Fosse ◽  
Marcella Costa Radael ◽  
João Carlos Fosse Filho ◽  
...  
Keyword(s):  
Larval Development ◽  
Mouth Opening ◽  
Digital Camera ◽  
Optical Microscope ◽  
Larval Period ◽  
Experimental Tank ◽  
Larval Stages ◽  
Average Temperature ◽  
Time Required ◽  
Embryonic And Larval Development

SummaryThe aim of this study was to describe the embryonic and larval development of discus fish (Symphysodon aequifasciatus), and to determine the time required, hours post fertilization (hpf), for the emergence of various structures. To describe embryonic and larval stages, observations were made at regular periods under an optical microscope and images were taken with a digital camera attached to a microscope. The average temperature reached in the experimental tank was 27.9°C. Important facts in embryonic and larval development are described, such as the closure of the blastopore, which occurred at 31.5 hpf; a period of eruption, which occurred at 58.5 hpf; and a mouth opening, which occurred at 90.5 hpf; and larvae that exhibited oriented swimming and eating exogenous food at 136.5 hpf.

Observations on nest dynamics and embryonic and larval development in the nest building gladiator frog, Hyla faber

1993 ◽  
Vol 14 (4) ◽  
pp. 411-421 ◽  
Author(s):  
Marcio Martins
Keyword(s):  
Larval Development ◽  
Related Species ◽  
Aquatic Insects ◽  
Rainy Season ◽  
Egg Laying ◽  
Nest Building ◽  
Southeastern Brazil ◽  
Water Evaporation ◽  
Similar Species ◽  
Embryonic And Larval Development

AbstractNests and larval development of the nest building gladiator frog, Hyla faber were studied in southeastern Brazil, during the rainy season of 1988-1989. Nests were built at the pond margins, exclusively by males, and varied in shape, size, and composition in relation to the substrate. Nests were used by 1-4 individual males and housed larvae for a mean of 26 days; 0-6 egg clutches were deposited in a nest. Larvae from individual clutches stayed inside the nests for 8-38 days. Embryonic development occurred within the first 210 h after fertilization and larval development, inside an enclosure installed in a pond, lasted over 8 months. Mortality inside the nests was due to nest water evaporation and/or drainage, to eggs sinking in the first hours after fertilization, or to predation by aquatic insects. Slow larval development in Hyla faber seems to be related to breeding in permanent ponds. Nest building in Hyla faber and related species may have evolved from the habit of using natural depressions for egg laying observed in other morphologically similar species.

Larval morphology and development of Aphidius rhopalosiphi (Hymenoptera: Braconidae: Aphidiinae)

2004 ◽  
Vol 136 (2) ◽  
pp. 169-180 ◽  
Author(s):  
Frédéric Muratori ◽  
Jo Le Lannic ◽  
Jean-Pierre Nénon ◽  
Thierry Hance
Keyword(s):  
Developmental Stages ◽  
Morphological Changes ◽  
Abundant Species ◽  
Larval Morphology ◽  
Aphid Parasitoid ◽  
Larval Stages ◽  
Immature Development ◽  
Aphidius Rhopalosiphi ◽  
Cereal Fields ◽  
Parasitoid Development

AbstractThe aphid parasitoid Aphidius rhopalosiphi is the most abundant species of Aphidiinae in cereal fields in northern Europe. Although the larval morphology of other Aphidiinae has been described, the morphology and immature development of A. rhopalosiphi remain unknown. Our goal is to relate growth and larval developmental stages to morphological changes during parasitoid development, using light and scanning electron microscopy. Aphidius rhopalosiphi develops through three larval stages with clear differences in the morphology of the mouthparts, tegument sculpturing, and respiratory features that can be related to the different constraints that the larvae have to face. In the first instar, adaptations to physical combat with competitors take the form of strong mandibles, active caudae, and dorsal spines that allow crawling motion. In the third instar, the larva is adapted to tear tissues with short hooked mandibles and to face aerial respiration. All instars possess sensory structures. The "three instars" hypothesis is supported here by the observation of larvae in exuviation. No differences were found between our observations and descriptions of other Aphidius species, supporting the idea that species of this genus cannot be distinguished by larval morphology but only by morphometric analysis. Some new features of the genus are presented for the first and second instars.

Sign in / Sign up

Export Citation Format

Share Document