Life history, trophic behavior, and description of Gamasellodes vermivorax n. sp. (Mesostigmata: Ascidae), a predator of nematodes and arthropods in semiarid grassland soils

1987 ◽  
Vol 65 (7) ◽  
pp. 1689-1695 ◽  
Author(s):  
David Evans Walter
Keyword(s):  
Life History ◽  
Sex Determination ◽  
Adult Female ◽  
Generation Time ◽  
Life Stages ◽  
Adult Males ◽  
Microcosm Experiment ◽  
Grassland Soils ◽  
Semiarid Grassland ◽  
Determination Mechanism

All life stages of Gamasellodes vermivorax n. sp. (Mesostigmata: Ascidae), a predator of mites, collembolans, and nematodes in semiarid grassland soils, are described. Female to female generation time is 10 days on a diet of rhabditid nematodes at 24 °C. Each adult female may produce one to three eggs daily for at least 2 weeks. Female deutonymphs are guarded by adult males. Isolated female deutonymphs molt to adults which begin laying eggs within 48 h of emergence. All eggs laid by unfertilized females develop into males, indicating a haplodiploid sex determination mechanism. In a microcosm experiment, nematode densities were negatively correlated with G. vermivorax densities.

Antennoseius (Vitzthumia) janus n.sp. (Acari: Ascidae), a mesostigmatic mite exhibiting adult female dimorphism

1989 ◽  
Vol 67 (5) ◽  
pp. 1291-1310 ◽  
Author(s):  
Evert E. Lindquist ◽  
David Evans Walter
Keyword(s):  
Sex Ratio ◽  
Adult Female ◽  
Generation Time ◽  
Egg Production ◽  
Low Density ◽  
Adult Males ◽  
Adult Females ◽  
As Species ◽  
Single Animal ◽  
The Impact

All instars of Antennoseius janus n.sp are described. Adult females occur as two distinct morphs, a nondispersing female with granular soft integument, barbed dorsal setae, emarginated opisthonotal shield, and fully developed sternal shield, and a dispersing female with smooth soft integument, nearly smooth dorsal setae, entire opisthonotal shield, and reduced sternal shield. Granular morph females begin egg production within 3 days of mating; however, smooth morph females delay reproduction for many weeks, apparently to disperse. Adult males and immatures have a granular soft integument and barbed setae similar to the granular morph females. Females produced in single animal or low density cultures (less than six individuals per culture) with excess food are granular morphs, whereas in more crowded cultures 5–100% of the maturing females are smooth morphs. This is the first example of adult female dimorphism confirmed experimentally for any family of mites in the entire order Mesostigmata of the Acari. The impact of this phenomenon on taxonomic concepts in the genus Antennoseius is discussed. A key is included, which distinguishes between the genera Anystipalpus Berlese, 1911 and Antennoseius Berlese, 1916, between the subgenera Antennoseius s.str. and Vitzthumia Thor, 1930, and between the seven forms of Vitzthumia currently regarded as species. All instars of A. janus are voracious predators of nematodes and small arthropods. Development from egg to adult takes 9–11 days on a diet of rhabditid nematodes at 23 °C. Generation time for granular morph females is about 14 days. Females require insemination before eggs can be laid, and the sex ratio is about 1 male: 1.3 females.

scholarly journals Hide-and-Seek with Tiny Neotenic Beetles in One of the Hottest Biodiversity Hotspots: Towards an Understanding of the Real Diversity of Jurasaidae (Coleoptera: Elateroidea) in the Brazilian Atlantic Forest

Biology ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 420
Author(s):  
Gabriel Biffi ◽  
Simone Policena Rosa ◽  
Robin Kundrata
Keyword(s):  
Atlantic Forest ◽  
Field Research ◽  
Transitional Zone ◽  
Biodiversity Hotspot ◽  
Biodiversity Hotspots ◽  
Brazilian Atlantic Forest ◽  
Life Stages ◽  
Adult Males ◽  
Undescribed Species ◽  
First Time

Jurasaidae are a family of neotenic elateroid beetles which was described recently from the Brazilian Atlantic Forest biodiversity hotspot based on three species in two genera. All life stages live in the soil, including the larviform females, and only adult males are able to fly. Here, we report the discovery of two new species, Jurasai miraculum sp. nov. and J. vanini sp. nov., and a new, morphologically remarkable population of J. digitusdei Rosa et al., 2020. Our discovery sheds further light on the diversity and biogeography of the group. Most species of Jurasaidae are known from the rainforest remnants of the Atlantic Forest, but here for the first time we report a jurasaid species from the relatively drier Atlantic Forest/Caatinga transitional zone. Considering our recent findings, minute body size and cryptic lifestyle of all jurasaids, together with potentially high numbers of yet undescribed species of this family from the Atlantic Forest and possibly also other surrounding ecoregions, we call for both field research in potentially suitable localities as well as for a detailed investigation of a massive amount of already collected but still unprocessed materials deposited in a number of Brazilian institutes, laboratories and collections.

scholarly journals Estimating the survival of unobservable life stages for a declining frog with a complex life history

Ecosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Jonathan P. Rose ◽  
Sarah J. Kupferberg ◽  
Clara A. Wheeler ◽  
Patrick M. Kleeman ◽  
Brian J. Halstead
Keyword(s):  
Life History ◽  
Life Stages ◽  
Complex Life History

Distribution and life history of caridean shrimps in regulated lowland rivers in southern Australia

2004 ◽  
Vol 55 (3) ◽  
pp. 295 ◽  
Author(s):  
A. J. Richardson ◽  
J. E. Growns ◽  
R. A. Cook
Keyword(s):  
Life History ◽  
Life Stages ◽  
Lowland Rivers ◽  
Flow Alteration ◽  
Eastern Australia ◽  
History Of ◽  
Paratya Australiensis ◽  
Juvenile Stages ◽  
Shrimp Abundance ◽  
Large Adult

Caridean shrimps are an integral component of lowland river ecosystems in south-eastern Australia, but their distributions may be affected by flow alteration. Monthly shrimp samples were collected from slackwaters in three hydrologically distinct sections of the heavily regulated Campaspe River and the less regulated Broken River for three consecutive years. The distributions of Paratya australiensis, Caridina mccullochi and Macrobrachium australiense, along with their life history in river sections with different hydrology are outlined. Paratya australiensis and M. australiense occurred in all sections, but C. mccullochi was absent from sections of the Campaspe River that received irrigation flows during summer/autumn. Shrimp larvae were most abundant in summer (December–February) and juvenile recruitment continued through to mid autumn (April). Breeding and recruitment of P. australiensis occurred for longer than other shrimps. Apart from large adult and berried M. australiense, all life stages of shrimps commonly occurred in slackwaters, particularly the larval and juvenile stages. Irrigation flows in summer/autumn probably adversely affect the size, extent and arrangement of slackwaters, at a time when they may be critical habitats for C. mccullochi larval development and recruitment. Dams and weirs in the Campaspe River may have influenced shrimp abundance and the timing of breeding.

Effects of adults on survival and recruitment of Peromyscus leucopus

1987 ◽  
Vol 65 (10) ◽  
pp. 2519-2523
Author(s):  
Gregory H. Adler ◽  
Mark L. Wilson ◽  
Michael J. DeRosa
Keyword(s):  
Adult Female ◽  
Adult Male ◽  
Peromyscus Leucopus ◽  
Survival Rates ◽  
Adult Males ◽  
Control Grid ◽  
Young Males ◽  
Young Females ◽  
Breeding Seasons ◽  
And Control

A population of Peromyscus leucopus (white-footed mouse) in northeastern Massachusetts was manipulated for 3 years to determine the effects of adults on survival and recruitment. Two experimental grids were established, from which either all adult males or all adult females were removed continually. The effects of these two manipulations were compared with demography on a control grid. Manipulations had no apparent effect on breeding intensity of young, survival rates of adults, or residency rates of adults and young. Recruitment of adult males was higher on the adult male removal grid than on the control grid. Recruitment rates of adult males and of young males and young females were lower on the adult female removal grid than on the control grid. Survival rates of young males were higher on the adult female removal grid than on the control grid; this effect may have been due to either reduced adult female residency or adult male recruitment. All differences between experimental and control grids were noted only during breeding seasons. Adult males apparently limited recruitment of adult consexuals. The effects of manipulations on other measured parameters were inconclusive because of high immigration rates of adult males onto the adult male removal grid and reduced recruitment of adult males and decreased production of young on the adult female removal grid.

High-Throughput Sequencing for Life-History Sorting and for Bridging Reference Sequences in Marine Gerromorpha (Insecta: Heteroptera)

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Jia Jin Marc Chang ◽  
Yin Cheong Aden Ip ◽  
Lanna Cheng ◽  
Ismael Kunning ◽  
Ralph R Mana ◽  
...  
Keyword(s):  
Life History ◽  
High Throughput Sequencing ◽  
Association Studies ◽  
Morphological Characters ◽  
Adult Males ◽  
Accurate Identification ◽  
Life History Stages ◽  
Coi Sequences ◽  
Primer Sets ◽  
Insect Taxonomy

Abstract Accurate identification and association of larval specimens with adults is a major challenge in insect taxonomy. Fortunately, it is now possible for nonexperts to sort collections of bulk samples with DNA barcodes rapidly and cost-effectively. We demonstrate this process using nanopore barcoding of 757 marine insects (Insecta: Gerromorpha), of which 81% were nymphs and many samples did not have co-occurring adult males for specific identification. We successfully associated 738 specimens (97%) to nine gerromorphan species, which would have been impossible to identify using morphological characters alone. This improved ability to incorporate information from all life-history stages has led to greater precision of species distributional ranges—knowledge that will be crucial for a more complete understanding of marine insects. We also highlighted two distinct, nonoverlapping Gerromorpha COI sequence databases on GenBank—a consequence of using two different primer sets to amplify different regions of COI. This issue inevitably hinders species identification with DNA-based methods, particularly for poorly represented groups such as marine insects. We bridged these databases by analyzing full-length COI sequences. We believe this will inspire future studies to incorporate DNA-based methods for more adult–larval association studies and for enhancing existing genetic resources, especially in understudied groups.

Key aspects of the primary sex determination mechanism are conserved across the genus Drosophila

Development ◽  
1998 ◽  
Vol 125 (16) ◽  
pp. 3259-3268 ◽  
Author(s):  
J.W. Erickson ◽  
T.W. Cline
Keyword(s):  
Sex Determination ◽  
Rapid Onset ◽  
Amino Acid Identity ◽  
Bzip Transcription Factor ◽  
Regulatory Sequence ◽  
Tightly Coupled ◽  
Pole Cells ◽  
High Level ◽  
Key Aspects ◽  
Determination Mechanism

In D. melanogaster, a set of ‘X:A numerator genes’, which includes sisterlessA (sisA), determines sex by controlling the transcription of Sex-lethal (Sxl). We characterized sisA from D. pseudoobscura and D. virilis and studied the timing of sisA and Sxl expression with single cell-cycle resolution in D. virilis, both to guide structure-function studies of sisA and to help understand sex determination evolution. We found that D. virilis sisA shares 58% amino acid identity with its melanogaster ortholog. The identities confirm sisA as an atypical bZIP transcription factor. Although virilis sisA can substitute for melanogaster sisA, the protein is not fully functional in a heterologous context. The putative sisA regulatory sequence CAGGTAG is a potential ‘numerator box,’ since it is shared with the other strong X:A numerator gene, sisB, and its target, SxlPe. Temporal and spatial features of sisA and SxlPe expression are strikingly conserved, including rapid onset and cessation of transcription in somatic nuclei, early cessation of sisA transcription in budding pole cells and persistent high-level sisA expression in yolk nuclei. Expression of sisA and Sxl is as tightly coupled in virilis as it is in melanogaster. Taken together, these data indicate that the same primary sex determination mechanism exists throughout the genus Drosophila.

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