The life history of Palmaria palmata in culture. A new type for the Rhodophyta

1980 ◽  
Vol 58 (11) ◽  
pp. 1250-1256 ◽  
Author(s):  
John P. van derMeer ◽  
Edna R. Todd
Keyword(s):  
Life History ◽  
Vegetative Growth ◽  
Palmaria Palmata ◽  
Recessive Mutation ◽  
Male And Female ◽  
Carpogonial Branch ◽  
History Of ◽  
New Type ◽  
Sexually Mature ◽  
Older Males

The life history of Palmaria palmata has been completed in culture. Tetraspores from diploid plants gave rise to male and female haploid plants which differed morphologically. Female plants were extremely small and became sexually mature only days after tetraspore release. Trichogynes were observed on plants only 4 days old, and remained conspicuous for several weeks. As the females aged, trichogynes declined in number and they could not be detected on plants 5 months old. In contrast, male plants required several (9–12) months of vegetative growth before they formed spermatia. As a consequence, females had to be fertilized by older males from preceding gametangial generations.The diploid tetrasporangial plants developed directly on fertilized females. As they enlarged, they completely overgrew the small females and formed their own holdfast attachments to the substrate. A recessive mutation resulting in green frond colour was used in crosses designed to yield red diploid tissue on green females after fertilization, thereby greatly facilitating observations on the development of the tetrasporangial phase.Preliminary observations indicate that the carpogonium is a single cell. There appears to be no carpogonial branch or auxilliary cell. The tetrasporangial phase develops from the zygote by simple mitotic divisions, suggesting that the life history is best interpreted as lacking a carposporophyte.

The life history of Chondrus crispus in culture

1972 ◽  
Vol 50 (5) ◽  
pp. 1055-1060 ◽  
Author(s):  
L. C-M. Chen ◽  
J. McLachlan
Keyword(s):  
Life History ◽  
Second Generation ◽  
Dorsal Surface ◽  
Similar Rate ◽  
Chondrus Crispus ◽  
Basal Disc ◽  
Male And Female ◽  
Rate Of Growth ◽  
History Of ◽  
Sexually Mature

The life history of the rhodophycean alga, Chondrus crispus, was completed in culture in about 20 months. Plants established from tetraspores formed male and female gametophytes and subsequently carposporophytes; carpospores in turn gave rise to plants with mature tetrasporangia. Tetraspores from these resulted in second generation gametophytes. Carpospores of plants from nature developed into tetrasporophytes; gametophytes derived from the tetraspores became sexually mature within a year. Sporophytic and gametophytic plants were, as expected, morphologically similar. Rate of growth of plants in cultures was comparable with published observations made on plants in nature. Preliminary experiments showed that, in culture, regeneration can occur from both the erect frond and the basal disc. In the latter, erect fronds may arise from any point on the dorsal surface of the disc.

The life history of Halosaccion ramentaceum

1981 ◽  
Vol 59 (4) ◽  
pp. 433-436 ◽  
Author(s):  
John P. van der Meer
Keyword(s):  
Life History ◽  
Chromosome Number ◽  
Sexual Maturity ◽  
Mutant Phenotype ◽  
Sexual Cycle ◽  
Palmaria Palmata ◽  
Male And Female ◽  
Haploid Male ◽  
History Of ◽  
Mendelian Transmission

The complete life history of Halosaccion ramentaceum has been determined. It is very similar to that of Palmaria palmata, consisting of haploid male and female gametophytes alternating with a diploid tetrasporophyte. As for P. palmata, there is no carposporophyte. Male and female gametophytes attain sexual maturity almost a generation apart. Whereas male plants require approximately 1 year's growth before producing spermatia, female gametophytes are microscopic and reach sexual maturity only a few days after tetraspore germination. The diploid tetrasporophyte initiates its development on the female, but almost immediately forms an independent holdfast on the substratum beside the female. The first diploid fronds arise from that holdfast after it is well established.The existence of a complete sexual cycle was proven by demonstrating: fertilization of trichogynes by spermatia; meiosis in tetrasporangia, with a chromosome number of n = ~24 in gametophytes and 2n = ~48 in tetrasporophytes; and by documenting the Mendelian transmission of a mutant phenotype from the male parent to the F1 gametophytes.

A contribution towards elucidating the life history of Palmaria palmate (=Rhodymenia palmata)

1976 ◽  
Vol 54 (24) ◽  
pp. 2903-2906 ◽  
Author(s):  
J. P. van der Meer
Keyword(s):  
Life History ◽  
Chromosome Number ◽  
Atlantic Coast ◽  
Palmaria Palmata ◽  
Haploid Chromosome Number ◽  
History Of

Palmaria palmata from a region of the Atlantic coast of Canada has been examined cytologically. Plants bearing tetrasporangia were found to be diploid with meiosis occurring in the tetrasporangia. Spermatangial plants and sporelings growing from tetraspores were haploid. The haploid chromosome number appears to be 22–23.

LIFE HISTORY STUDIES OF THE TOBACCO FLEA BEETLE, EPITRIX HIRTIPENNIS (MELSHEIMER) (COLEOPTERA: CHRYSOMELIDAE)

1987 ◽  
Vol 22 (3) ◽  
pp. 237-244 ◽  
Author(s):  
W. Davis Martin ◽  
G. A. Herzog
Keyword(s):  
Life History ◽  
Larval Stage ◽  
Flea Beetle ◽  
Pupal Stage ◽  
Adult Emergence ◽  
Adult Longevity ◽  
Male And Female ◽  
Controlled Conditions ◽  
History Of ◽  
The Mean

The life history of the tobacco flea beetle, Epitrix hirtipennis (Melsheimer) (= Epitrix parvula Fab.) was studied under the controlled conditions of 27 ± 2.8°C, 80 ± 6% and a 14L:10D photophase. Eggs matured in ca. 4 days, the larval stage, including 3 instars, developed in 13 days, prepupal development took 3 days and the pupal stage lasted approximately 5 days. There was a 24 day interval between oviposition and adult emergence. Females laid 3.1 eggs/day with a 13 day period between adult emergence and first oviposition. The mean number of total eggs/female was 138.6 ± 14.7. Female oviposition continued until a few days before death and adult longevity was approximately 70 days. A visual means of distinguishing between male and female beetles was also developed.

scholarly journals On the Life-History of Helicosporidium parasiticum, n.g., n.sp., a new type of Protist parasitic in the Larva of Dasyhelea obscura Winn. (Diptera, Ceratopogonidae) and in some other Arthropods

Parasitology ◽  
1921 ◽  
Vol 13 (2) ◽  
pp. 97-113 ◽  
Author(s):  
D. Keilin
Keyword(s):  
Life History ◽  
Horse Chestnut ◽  
History Of ◽  
New Type

The usual host of this new parasite, Helicosporidium parasiticum, is the larva of a Ceratopogonid, Dasyhelea obscura Winnertz, which lives in the decomposed sap filling the wounds of trees—elm and horse-chestnut. All the material used for this study was derived from the wounds of two trees only: (1) an elm tree standing on the Caius College ground at Newnham, facing Church Rate Walk, and (2) a horse-chestnut standing between the School of Agriculture and Downing College.

The Development and Life History of Echinorhynchus truttae Schrank, 1788 (Acanthocephala)

1966 ◽  
Vol 40 (1-2) ◽  
pp. 11-32 ◽  
Author(s):  
J. B. E. Awachie
Keyword(s):  
Life History ◽  
Embryonic Development ◽  
Intermediate Host ◽  
Definitive Host ◽  
Room Temperature ◽  
Final Host ◽  
Gammarus Pulex ◽  
Pyloric Region ◽  
History Of ◽  
Sexually Mature

The details of the post-embryonic development of Echinorhynchus truttae in the intermediate host, Gammarus pulex, and the final host, Salmo truttae, are described.The cystacanths of this species are sexually mature and are formed about 82 days after infection at room temperature, ca. 17°C.Copulation takes place in the definitive host soon after the worms enter the pyloric region of the intestine. About 10 weeks after infection, mature eggs are passed out with the faeces of fish.

Life history of aggression in Anastatus disparis (Hymenoptera: Eupelmidae) with extreme male–male combat

2020 ◽  
pp. 1-7 ◽  
Author(s):  
Peng-Cheng Liu ◽  
De-Jun Hao ◽  
Wei Hu ◽  
Jian-Rong Wei ◽  
Jian-Jun Wang
Keyword(s):  
Life History ◽  
Parasitoid Wasp ◽  
Reproductive Value ◽  
Supporting Evidence ◽  
Resource Holding Potential ◽  
Wasp Species ◽  
Young Males ◽  
Study Results ◽  
History Of ◽  
Older Males

Abstract Aggressive behaviour is common in animals and typically has lifetime consequences. As younger males have higher residual reproductive value than older males and lose more from injuries than older males do, the propensity for fighting tends to increase with age in many empirical reports and species. However, fighting patterns in those empirical reports cannot confirm the hypothesis that individuals cannot readily inflict injuries on their opponents. To address this shortcoming, a parasitoid wasp species, Anastatus disparis (Hymenoptera: Eupelmidae), was used as an experimental model to explore the characteristics of aggression from a life-history perspective; this wasp exhibits extreme fighting, resulting in contestants experiencing injury and death. Results showed that the energetic costs of fighting to injury significantly shortened life and caused the loss of most mating ability. Inconsistent with general predictions, the frequency and intensity of fighting in A. disparis significantly decreased with male age. Further study results showed significantly more young males were received by and successfully mated with virgin females, and most genes related to energy metabolism were downregulated in aged males. Our study provided supporting evidence that young A. disparis males show more aggression likely because of their resource holding potential and sexual attractiveness decline with age.

The Life History of the Cirratulid Worm, Cirriformia Tentaculata, on an Intertidal Mudflat

1964 ◽  
Vol 44 (1) ◽  
pp. 47-65 ◽  
Author(s):  
J. D. George
Keyword(s):  
Growth Rate ◽  
Life History ◽  
Seasonal Variation ◽  
Annual Cycle ◽  
Seasonal Fluctuation ◽  
Mortality Data ◽  
Intertidal Mudflat ◽  
History Of ◽  
Causes Of Mortality ◽  
Sexually Mature

The seasonal fluctuation in numbers of C. tentaculata was investigated from December 1959 until February 1962. The lowest numbers were recorded in April followed by a rapid increase in numbers during May. The magnitude of the increase varied from year to year, as also did the number of peaks that occurred during the summer months.The worm was shown to have an extended breeding season from the end of March to September during which several spawning ‘bursts’ took place. Experiments suggest that some spawning may occur when the mudflat is inundated by the rising tide, although spawning was not observed in the field.The population of C. tentaculata exhibited an annual cycle of growth which was influenced by the seasonal variation in temperature. Laboratory observations suggest that a temperature of about 20° C is optimal for the growth of young worms. The growth rate (8 mm/year) is slow compared with that of other polychaetes.It is tentatively concluded from the field mortality data that between 10 and 16 % of animals survive to an age at which they are sexually mature; between 6 and 8 % of each generation reach an age of 15 months. Causes of mortality in the population are briefly discussed.

Life History of the Endemic Saddleback Crayfish, Faxonius medius (Faxon, 1884), (Decapoda: Cambaridae) in Missouri, USA

2019 ◽  
Vol 24 (1) ◽  
pp. 1-13 ◽  
Author(s):  
Robert DiStefano ◽  
Jacob Westhoff ◽  
Christopher Rice ◽  
Amanda Rosenberger
Keyword(s):  
Life History ◽  
Sympatric Species ◽  
First Year ◽  
Geographic Context ◽  
Ratio Size ◽  
Small Streams ◽  
History Of ◽  
Egg Brooding ◽  
First Year Of Life ◽  
Sexually Mature

Abstract The saddleback crayfish, Faxonius medius (Faxon, 1884), is endemic to a single drainage in eastern Missouri, USA, that is affected by heavy metals mining, and adjacent to a rapidly-expanding urban area. We studied populations of F. medius in two small streams for 18 months to describe the annual reproductive cycle and gather information about fecundity, sex ratio, size at maturity, and size-class structure. We also obtained information about the species’ density at supplemental sites. The species, though rare in a geographic context, is locally abundant; we captured a monthly average of more than 75 F. medius from each of the two study populations. Densities of F. medius were high relative to several sympatric species of Faxonius Cope, 1872 and Cambarus Erichson, 1846. The species exhibited traits of an r-strategist life history; it was relatively short-lived and early to maturity. Its fecundity and egg size were comparable to Ozark congeners. Breeding season occurred in autumn, perhaps extending into early winter. Egg brooding occurred primarily in April. Young-of-year first appeared in samples in June. We estimated that these populations contained 2 to 3 size-classes, and most individuals became sexually mature in their first year of life. Life history information presented herein will be important for future conservation efforts.

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