Taxonomic Status of Calanus finmarchicus and C. glacialis (Copepoda), with Special Reference to Adult Males

1971 ◽  
Vol 28 (1) ◽  
pp. 23-30 ◽  
Author(s):  
Bruce W. Frost
Keyword(s):  
Vertical Distribution ◽  
Special Reference ◽  
Geographical Distribution ◽  
Morphometric Analysis ◽  
Taxonomic Status ◽  
Life Cycles ◽  
Calanus Finmarchicus ◽  
Adult Males ◽  
Adult Females ◽  
Taxonomic Studies

A morphometric analysis using certain taxonomic characters of adult males of Calanus finmarchicus (Gunnerus) and C. glacialis Jaschnov shows that the taxa comprise two non-overlapping clusters. Calanus finmarchicus and C. glacialis are probably reproductively isolated. Differences between the species in geographical distribution, vertical distribution, and timing of life cycles also support this conclusion. Previous taxonomic studies of adult females of the two species have yielded inconclusive results, probably because the analyses were based largely on subgeneric characters.

Vertical distribution of Paralabidocera antarctica (Copepoda : Calanoida) in Ace Lake, Antarctica, in summer

1987 ◽  
Vol 38 (4) ◽  
pp. 537 ◽  
Author(s):  
IAE Bayly ◽  
HR Burton
Keyword(s):  
Population Density ◽  
Vertical Distribution ◽  
Vertical Profile ◽  
Meromictic Lake ◽  
Adult Males ◽  
Vertical Column ◽  
Adult Females ◽  
Two Peaks ◽  
Paralabidocera Antarctica

In an ice-covered (thickness 1.68 m) meromictic lake, in early January 1982, a vertical profile of the population density of P. antarctica showed two peaks: from 7 to 130 cm beneath the ice, and just above the anoxylimnion at 10.0-10.5 m. Copepodite stages 111 and IV were dominant in the first (shallow) peak and stage CV was dominant in the second (deep) peak. Significantly more adult males than females were present within an entire vertical column of oxylimnion, but more adult females than males were present in a stratum 30 cm thick immediately beneath the ice.

The Late Helladic IIIC Intramural Burials at Lefkandi, Euboea

1991 ◽  
Vol 86 ◽  
pp. 273-296 ◽  
Author(s):  
J.H. Musgrave ◽  
M. Popham
Keyword(s):  
Special Reference ◽  
Child Mortality ◽  
Oral Hygiene ◽  
Adolescent Female ◽  
Adult Males ◽  
Adult Females ◽  
Adult Stature

The aim of this paper is to describe and assess the intramural burials from the Lefkandi Settlement (Xeropolis). In all 20 individuals were inhumed within the walls, comprising 3 adult males, 2 adult females, one possible adolescent female and 14 children. The last ranged in age from birth to 9 years. Routine matters such as child mortality, adult stature, pathology and oral hygiene are discussed, with special reference to both the Settlement burials and to the inhumed material scattered throughout the Cemeteries.

The reproductive biology of Corophium volutator and C. arenarium (Crustacea: Amphipoda)

1979 ◽  
Vol 59 (2) ◽  
pp. 355-368 ◽  
Author(s):  
J. D. Fish ◽  
A. Mills
Keyword(s):  
Spring Tide ◽  
Life Cycles ◽  
Rhythmic Pattern ◽  
Adult Males ◽  
Corophium Volutator ◽  
Adult Females ◽  
Initial Rupture ◽  
Two Generations ◽  
Embryonic Life ◽  
Tide Period

The life-cycles of Corophium volutator (Pallas) and C. arenarium Crawford in the Dovey Estuary are based on two generations per year. Reproduction is well established by April and although the overwintering generation dies during the summer, reproduction continues until October as a result of the breeding of summer-generation animals. The mean brood size of C. volutator is greater than that of C. arenarium and both species show high levels of egg loss from the brood pouch. Hatching and moulting of the embryonic cuticle take place simultaneously and the initial rupture of the egg membranes is made by spines on the cuticle of the telson of the future free-living animal. These spines persist throughout post-embryonic life.Adult females of both species show a semi-lunar breeding rhythmicity and, associated with this, adult males show a rhythmic pattern of crawling behaviour. As the tide ebbs during the rising spring tide period, adult males emerge from the sediment and crawl across the mud surface in search of burrows occupied by adult females. It is concluded that copulation takes place in the burrow and not in the water column.

scholarly journals The Vertical Distribution of Marine Macroplankton. VII Observations on the Behaviour of Calanus finmarchicus

1928 ◽  
Vol 15 (2) ◽  
pp. 429-454 ◽  
Author(s):  
F. S. Russell
Keyword(s):  
Light Intensity ◽  
Vertical Distribution ◽  
Seasonal Change ◽  
Life Cycles ◽  
Calanus Finmarchicus ◽  
Low Light ◽  
Copepodid Stage ◽  
Males And Females ◽  
The Vertical Distribution ◽  
Trawl Catches

SUMMARYThe vertical distribution of Calanus finmarchicus adults in the daylight in the Plymouth region as shown by stramin ring-trawl catches in described for the period April to September in 1926. The general results confirmed the indications given in 1925 that there is a, gradual descent of the region of maximum abundance from about 10 metres in April to-metres in June, with a definite rise towards the surface ia July, August, and September.2. The rise towards the surface was evident on sunny days as well as dull, indicating that the suggestion that dull weather and low light intensity was its cause in 1925 may possibly have been incorrect.Measurements of the total lengths of Calanus were made which showed a seasonal change, a brood of small adults occurring in July, August, and September, as opposed to a brood of large adults whichdominated in the spring.It is suggested that possibly these two broods are physiologically different, and that the small type of adult prefers a higher light intensity and lives nearer the surface than the large type.The males and females differed in their behaviour, the males being always slightly deeper in the water than the females.Some indications are given of the course of the life-cycles of Calanus in the Plymouth area.While from April to the end of June the abundance of the last copepodid stage (Stage V) rarely exceeded more than 20% of the total Calanus in any one catch, they became very much more abundant in July, August, and September, reaching even 60% and 70%.

Taxonomic revision of Cypridopsis silvestrii comb. nov. (Ostracoda, Crustacea) from Patagonia, Argentina with morphometric analysis of their intraspecific shape variability and sexual dimorphism

Zootaxa ◽  
2019 ◽  
Vol 4563 (1) ◽  
pp. 83
Author(s):  
ALEJANDRA P. PÉREZ ◽  
CORINA A. COVIAGA ◽  
LORENA Y. RAMOS ◽  
JULIO LANCELOTTI ◽  
MARTA S. ALPERIN ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
Geographical Distribution ◽  
Morphometric Analysis ◽  
Taxonomic Status ◽  
Taxonomic Revision ◽  
Present Contribution ◽  
Morphological Variations ◽  
Ecological Requirements ◽  
Morphometric Analyses ◽  
Southern Patagonia

In this study we redescribe an ostracod species belonging to the subfamily Cypridopsinae Kaufmann, 1900, sampled in seven localities of northern and southern Patagonia, Argentina. A new taxonomical combination is proposed, Cypridopsis silvestrii comb. nov., based on detailed description of females and the first descriptions of males. Cypridopsis silvestrii occurred on a wide geographical distribution range, from 40º to 48º S latitude, as well as broad environmental tolerance ranges. We evaluated morphological variations in two populations of C. silvestrii from northern (El Toro lake) and southern (El Sello lake) Patagonia, with contrasting limnological conditions. El Toro is a small shallow lake with high salinity waters and El Sello is a large deep lake with lower salinity. Based on morphometric analysis, our results showed intraspecific variation in valve shape and size between populations. Sexual dimorphism in El Toro population was identified through morphometric analyses. Additionally, comparison of valve outlines in living and subfossil individuals from El Toro lake allowed specimens previously described as juveniles of Eucypris fontana (Graf, 1931) to be identified as adults of C. silvestrii comb. nov. The present contribution increases knowledge of the taxonomic identity, the ecological requirements and the geographical distribution of C. silvestrii, and shows that morphometric analyses are a feasible and useful tool for exploring intraspecific shape differences and assisting in taxonomic identification. Furthermore, the results presented herein provide tools for C. silvestrii identification in paleolimnological studies, and emphasize the usefulness of studying living representatives for clarification of the taxonomic status of species widely distributed in Quaternary sediments. 

Two new species and taxonomic notes on the Neotropical spiny orb-weaving spi-ders Micrathena and Chaetacis (Araneae: Araneidae), with remarks on the development of Micrathena excavata IVAN L. F. MAGALHÃES & ADALBERTO J. SANTOS (Brazil)

Zootaxa ◽  
2011 ◽  
Vol 2983 (1) ◽  
pp. 39 ◽  
Author(s):  
IVAN L. F. MAGALHÃES ◽  
ADALBERTO J. SANTOS
Keyword(s):  
New Species ◽  
Junior Synonym ◽  
Adult Males ◽  
Development Stages ◽  
Brazilian Amazonia ◽  
Central Brazil ◽  
Adult Females ◽  
Two New Species ◽  
Senior Synonym ◽  
First Time

In this paper, M. yanomami n. sp., from Brazilian Amazonia, Chaetacis bandeirante n. sp., from Central Brazil, and the males of M. gaujoni Simon, 1897 and M. ruschii (Mello-Leitão, 1945) n. comb. , respectively from Ecuador and Brazil, are described and illustrated for the first time. An ontogenetic series of the last development stages of both sexes of Micrathena excavata (C. L. Koch, 1836) is illustrated and briefly described. Adult females are larger and have longer legs and larger abdomens than adult males. Probably females undergo at least one additional moult before adulthood, compared to males. Micrathena ornata Mello-Leitão, 1932 is considered a junior synonym of M. plana (C. L. Koch, 1836), and M. mastonota Mello-Leitão 1940 is synonymized with M. horrida (Taczanowski, 1873). Acrosoma ruschii Mello-Leitão, 1945 is revalidated, transferred to Micrathena and considered a senior synonym of M. cicuta Gonzaga & Santos, 2004. Chaetacis necopinata (Chickering, 1960) is recorded for Brazil for the first time. Chaetacis incisa (Walckenaer, 1841) is considered a nomen dubium.

Spacing, movements, and habitat selection of the river otter in boreal Alberta

1994 ◽  
Vol 72 (7) ◽  
pp. 1314-1324 ◽  
Author(s):  
D. G. Reid ◽  
T. E. Code ◽  
A. C. H. Reid ◽  
S. M. Herrero
Keyword(s):  
Lontra Canadensis ◽  
Home Ranges ◽  
Adult Males ◽  
Movement Rates ◽  
River Otters ◽  
Aquatic Mammal ◽  
Adult Females ◽  
Two Factors ◽  
Bog Lakes ◽  
Selection Of

Seasonal spacing patterns, home ranges, and movements of river otters (Lontra canadensis) were studied in boreal Alberta by means of radiotelemetry. Adult males occupied significantly larger annual home ranges than adult females. Males' ranges overlapped those of females and also each other's. In winter, home ranges of males shrank and showed less overlap. Otters often associated in groups, the core members typically being adult females with young, or adult males. Otters tended to be more solitary in winter. In winter, movement rates of all sex and age classes were similar, and much reduced for males compared with those in other seasons. These data indicated a strong limiting effect of winter ice on behaviour and dispersion. We tested the hypothesis that otters select water bodies in winter on the basis of the suitability of shoreline substrate and morphology for dens with access both to air and to water under ice. Intensity of selection was greatest in winter, with avoidance of gradually sloping shorelines of sand or gravel. Adults selected bog lakes with banked shores containing semi-aquatic mammal burrows, and lakes with beaver lodges. Subadults selected beaver-impounded streams. Apart from human harvest, winter habitats and food availability in such habitats are likely the two factors most strongly limiting otter density in boreal Alberta.

Time-Budgets of Camargue Horses Ii. Time-Budgets of Adult Horses and Weaned Sub-Adults

Behaviour ◽  
1980 ◽  
Vol 72 (1-2) ◽  
pp. 26-48 ◽  
Author(s):  
Patrick Duncan
Keyword(s):  
Social Structure ◽  
Social System ◽  
General Trend ◽  
Small Population ◽  
Time Budgets ◽  
Adult Males ◽  
Adult Females ◽  
Young Horses

AbstractTime-budgets of adult and weaned sub-adult horses were studied in a small population of Camargue horses living in semi-liberty. The categories of activities used were: Standing resting, Lying flat, Lying up, Standing alert, Walking, Trotting, Galloping, Rolling and Foraging. The main differences in time-budgets were related to age and to sex : young horses spent more time lying (sleeping), males spent more time standing alert and in rapid movements (trot, gallop), while usually foraging less than did the adult females. During the three years of the study the population increased from 20 to 54 horses and there were considerable changes in social structure as the number of adult males increased. Associated with these developments there were some changes between years in the time-budgets: the most striking of which was a general trend for all horses to spend less time lying. Nonetheless the time-budgets showed a considerable constancy across years and age/sex-classes, especially with regard to time spent foraging. This conclusion may provide a clue as to why horses have an unusual social system based on long term relationships between a male and the females of his harem.

Extrinsic Inter- and Intra-specific Competition in Parasitoid Wasps

2021 ◽  
Vol 67 (1) ◽  
Author(s):  
Paul J. Ode ◽  
Dhaval K. Vyas ◽  
Jeffrey A. Harvey
Keyword(s):  
Developmental Stages ◽  
Interference Competition ◽  
Apparent Competition ◽  
Annual Review ◽  
Publication Date ◽  
Natural Ecosystem ◽  
Adult Males ◽  
Alternate Host ◽  
Adult Females ◽  
Behavioral Mechanisms

The diverse ecology of parasitoids is shaped by extrinsic competition, i.e., exploitative or interference competition among adult females and males for hosts and mates. Adult females use an array of morphological, chemical, and behavioral mechanisms to engage in competition that may be either intra- or interspecific. Weaker competitors are often excluded or, if they persist, use alternate host habitats, host developmental stages, or host species. Competition among adult males for mates is almost exclusively intraspecific and involves visual displays, chemical signals, and even physical combat. Extrinsic competition influences community structure through its role in competitive displacement and apparent competition. Finally, anthropogenic changes such as habitat loss and fragmentation, invasive species, pollutants, and climate change result in phenological mismatches and range expansions within host–parasitoid communities with consequent changes to the strength of competitive interactions. Such changes have important ramifications not only for the success of managed agroecosystems, but also for natural ecosystem functioning. Expected final online publication date for the Annual Review of Entomology, Volume 67 is January 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

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