Diversity in metabolic adaptation of pelagic larval stages of two sympatric species of brachyuran crabs

1973 ◽  
Vol 7 ◽  
pp. 434-446 ◽  
Author(s):  
A.N. Sastry ◽  
J.F. McCarthy
Author(s):  
Qusaie Karam ◽  
Zainab Al-Wazzan

Abstract Petroleum hydrocarbons (PH) toxicity and bioaccumulation in aquatic organisms have been investigated for almost 50 years. Continuous oil spillages necessitate a further understanding of the toxicological effects of PH on brachyuran crabs. Crabs can be exposed to PH through various routes such as the water column, sediment and diet. Numerous investigations have been dedicated to evaluating PH toxicity on different life stages of crab species, but the majority of them have focused on the blue crab Callinectes sapidus as it represents an edible and favourable seafood commodity for human consumption. The objective of the review is to critically assess studies related to PH toxicity on different life stages of 41 crab species representing 13 families across the world. Several physiological, biochemical and genetic endpoints of marine crabs were evaluated in addition to the sublethal effects of PH on crab metabolism, behaviour, moulting, growth and survival. A concise summary of PH deleterious effects on different taxonomic species of marine crabs is discussed and provides evidence that crabs can be used as indicator organisms of biomarker significance for marine pollution. Overall, larval stages appeared to be the most sensitive to the deleterious effects of PH compared with juveniles and adults. However, adult stages have received more research attention than other life stages, followed by larval stages, and juvenile stages are the least investigated stages with respect to PH toxicity. Finally, hepatopancreas and gills were the organs where greatest accumulation of PH was recorded.


2017 ◽  
Vol 98 (6) ◽  
pp. 1435-1453 ◽  
Author(s):  
Elena S. Kornienko ◽  
Darya D. Golubinskaya ◽  
Olga M. Korn ◽  
Svetlana N. Sharina

The complete larval development of the lobster shrimpLeonardsaxius amurensis(Kobjakova, 1937) (Decapoda: Axiidea: Axiidae) is described and illustrated for the first time. The first zoeae of this species were collected from the plankton samples and reared in the laboratory before moulting to the megalopa. A molecular genetic analysis based on comparison of partial mitochondrial COI, 12S rDNA and 16S rDNA sequence data confirmed the identity of axiid larvae found in the plankton andL. amurensisadults collected in the same area. The larval development ofL. amurensisincludes five zoeal stages and a single megalopa. Zoeae I ofL. amurensisare characterized by the presence of one short posterodorsal spine on the fifth pleonite in contrast to the larvae of related sympatric speciesBoasaxius princepshaving four posterodorsal spines on the pleonites 2–5.Leonardsaxius amurensisoccupies an intermediate position between lobster shrimps with abbreviated pelagic development (2–3 zoeal stages) and species with long development (up to eight zoeal stages). Thus, the number of zoeal stages in the family Axiidae varies widely, similarly to that in the families Callianassidae and Upogebiidae.


Zootaxa ◽  
2020 ◽  
Vol 4767 (2) ◽  
pp. 332-344
Author(s):  
STINE GRIEP ◽  
JULIAN GLOS

The genus Heterixalus is endemic to Madagascar. It contains eleven species of small to medium-sized tree frogs that typically inhabit open areas like swamps and rice fields. We describe the larval stages of three sympatric species that occur in western Madagascar: H. tricolor, H. carbonei, and H. luteostriatus. Similar to other species of this genus, the tadpoles of these species have a depressed, ovoid body-form and a generalized oral disc. The labial tooth row formula is 1/3(1). Examined phenotypes differed marginally between species. Compared to H. tricolor and H. carbonei, H. luteostriatus showed fewer cusps on the fork-like labial teeth, a lower ventral fin, and a shorter tail. The high morphological resemblance implicates an ecological similarity between species. Highly overlapping niches raise questions on how species co-occur. 


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Lucas Arantes-Garcia ◽  
Renata A. Maia ◽  
Patrícia Valadão ◽  
Yumi Oki ◽  
Geraldo Wlson Fernandes

Host plant quality is determinant for herbivorous insects performance and survival. While on larval stages, insects select their host plants based on factors such as leaf nitrogen and water content, digestibility, and defences. Of great interest is the coevolutionary relationship between the Heliconiini insects and the Passiflora plants. In this study we experimentally evaluated Dryas iulia (Nymphalidae) larval preference to four sympatric Passiflora (Passifloraceae) and subsequently, the larval performance on the two most consumed species. We tested the hypothesis that D. iulia larvae prefer the Passiflora species with higher nutritional quality and lower defence, which supports the greatest larval performance. Dryas iulia larvae preferred P. misera (60.5% leaf consumption) over P. pohlii (28.9%), P. suberosa (15.5%), and P. edulis (not consumed). Passiflora misera presented the highest N concentration, third in water content, second in tector trichomes, and no glandular trichomes (only P. suberosa did). Nitrogen best explained D. iulia larvae leaf consumption; which further explains the greatest larval performance in P. misera than in P. suberosa: i.e. higher survival (23.1%), conversion efficiency of ingested food (32.8%), relative growth rate (14.8%), heavier pupae (15.2%), and lower relative consumption rate (13.8%). This study creates the opportunity to further investigate the Heliconiini-Passiflora system and showed that D. iulia larvae can assess and choose the host plant (even among sympatric species) that supports the greatest performance.


Zootaxa ◽  
2012 ◽  
Vol 3204 (1) ◽  
pp. 1 ◽  
Author(s):  
ANDREA G. KOETTKER ◽  
PAULO Y.G. SUMIDA ◽  
RUBENS M. LOPES ◽  
ANDREA S. FREIRE

Approximately 370 brachyuran species have so far been recorded from the Brazilian coast, 123 of which have had theirlarval stages fully or partially described. The pictorial guide allows the identification of the first zoea of 110 species. Theremaining 13 species with known larval stages are treated to the genus level because of difficulties in the morphological differentiation of closely related species.


Author(s):  
G.C. Bellolio ◽  
K.S. Lohrmann ◽  
E.M. Dupré

Argopecten purpuratus is a scallop distributed in the Pacific coast of Chile and Peru. Although this species is mass cultured in both countries there is no morphological description available of the development of this bivalve except for few characterizations of some larval stages described for culture purposes. In this work veliger larvae (app. 140 pm length) were examined by the scanning electron microscope (SEM) in order to study some aspects of the organogenesis of this species.Veliger larvae were obtained from hatchery cultures, relaxed with a solution of MgCl2 and killed by slow addition of 21 glutaraldehyde (GA) in seawater (SW). They were fixed in 2% GA in calcium free artificial SW (pH 8.3), rinsed 3 times in calcium free SW, and dehydrated in a graded ethanol series. The larvae were critical point dried and mounted on double scotch tape (DST). To permit internal view, some valves were removed by slightly pressing and lifting the tip of a cactus spine wrapped with DST, The samples were coated with 20 nm gold and examined with a JEOL JSM T-300 operated at 15 KV.


2020 ◽  
Vol 4 (4) ◽  
pp. 365-381
Author(s):  
Ny Anjara Fifi Ravelomanantsoa ◽  
Sarah Guth ◽  
Angelo Andrianiaina ◽  
Santino Andry ◽  
Anecia Gentles ◽  
...  

Seven zoonoses — human infections of animal origin — have emerged from the Coronaviridae family in the past century, including three viruses responsible for significant human mortality (SARS-CoV, MERS-CoV, and SARS-CoV-2) in the past twenty years alone. These three viruses, in addition to two older CoV zoonoses (HCoV-229E and HCoV-NL63) are believed to be originally derived from wild bat reservoir species. We review the molecular biology of the bat-derived Alpha- and Betacoronavirus genera, highlighting features that contribute to their potential for cross-species emergence, including the use of well-conserved mammalian host cell machinery for cell entry and a unique capacity for adaptation to novel host environments after host switching. The adaptive capacity of coronaviruses largely results from their large genomes, which reduce the risk of deleterious mutational errors and facilitate range-expanding recombination events by offering heightened redundancy in essential genetic material. Large CoV genomes are made possible by the unique proofreading capacity encoded for their RNA-dependent polymerase. We find that bat-borne SARS-related coronaviruses in the subgenus Sarbecovirus, the source clade for SARS-CoV and SARS-CoV-2, present a particularly poignant pandemic threat, due to the extraordinary viral genetic diversity represented among several sympatric species of their horseshoe bat hosts. To date, Sarbecovirus surveillance has been almost entirely restricted to China. More vigorous field research efforts tracking the circulation of Sarbecoviruses specifically and Betacoronaviruses more generally is needed across a broader global range if we are to avoid future repeats of the COVID-19 pandemic.


2020 ◽  
Vol 324 (2) ◽  
pp. 242-251
Author(s):  
L.P. Flyachinskaya ◽  
P.A. Lezin

The paper considers the development of Ciliatocardium ciliatum from the stage of straight hinge to juvenile. In the White Sea the spawning of C. ciliatum begins at the end of June, larvae at different stages of development occur in plankton until the end of September. The earliest of the larvae found had shell lengths of 123–130 µm. The paper first examined the anatomy and structure of the larval shell of C. ciliatum. During the development, the main stages of organogenesis were described and special attention was paid to the formation of the digestive and muscular systems. The digestive system begins to function when the larva reaches a size of 170–180 µm. The digestive gland has a two-blade shape and is shifted to the right side. The foot is formed at a size of 230 µm, the gill rudiments appear when the larva reaches 270 µm. The development of the larval shell and larval hinge of the mollusc is considered in detail. The development of the larval shell of C. ciliatum is similar to the development of other family members. Throughout all the larval stages, the shell has a rounded shape with a low umbos, and the prodissoconch II has a clearly visible concentric structure. The C. ciliatum larval hinge is characterized by weak differentiation and the absence of pronounced cardinal teeth typical for other Cardiidae. However, the lateral structures of the castle – ridges and flanges – are well developed. The ligament begins to form at a size of 240–250 µm and occupies a lateral position. The settlement of the cockle takes place in September in the subtidal zone. After the metamorphosis, a large radial sculpture is formed on the dissoconch and a number of small spikes are formed at the rib of the posterior shoulder.


Sign in / Sign up

Export Citation Format

Share Document