STUDIES ON CESTODES OF THE GENUS TRIAENOPHORUS FROM FISH OF LESSER SLAVE LAKE, ALBERTA: V. DESCRIPTION AND LIFE HISTORY OF TRIAENOPHORUS STIZOSTEDIONIS N.SP.

1945 ◽  
Vol 23d (5) ◽  
pp. 117-127 ◽  
Author(s):  
Richard B. Miller
Keyword(s):  
Life History ◽  
Male Genitalia ◽  
Sexual Maturity ◽  
Morphological Characters ◽  
Parietal Peritoneum ◽  
Stizostedion Vitreum ◽  
Pike Perch ◽  
History Of

Triaenophorus stizostedionis is a pseudophyllidean cestode that occurs as an adult in the intestine of the pike-perch, Stizostedion vitreum. It differs from T. crassus and T. nodulosus in several morphological characters but particularly in the shape of the scolex hooks and the size and disposition of the male genitalia. Sexual maturity is attained in the spring; spawning and death take place during the first two weeks of June. The eggs average 56 μ long by 40 μ wide. The coracidia average 73 by 71 μ. The procercoid develops in the copepod, Cyclops bicuspidatus, in from 10 days to two weeks. When fully grown it reaches 220 μ. The plerocercoids occur encysted on the visceral and parietal peritoneum of the trout-perch, Percopsis omiscomaycus. The life history is completed when an infested trout-perch is swallowed by a pike-perch.

On the Correlation of the Life-history of the Acephaline Gregarine, Gonospora, with the Sexual Cycle of its Host

Parasitology ◽  
1930 ◽  
Vol 22 (4) ◽  
pp. 505-509 ◽  
Author(s):  
C. C. Hentschel
Keyword(s):  
Life History ◽  
Sexual Maturity ◽  
Sexual Cycle ◽  
History Of

1. In general there is a correlation between the life-history of Gonospora arenicolae and the sexual cycle of its host, Arenicola ecaudata, similar to that between G. varia and Audouinia tentaculata.2. In the species under consideration the correlation is not so definite and the life-history of a generation of parasites does not necessarily coincide with a sexual cycle of the host. This is complicated by the double annual spawning of the host.3. The formation of sporocysts is simultaneous with the sexual maturity of the worm.4. It is suggested that, as in Audouinia, a secretion produced by the gonads stimulates the development of the gregarine.5. The ejection of the sporocysts with the gametes was observed.6. It is suggested that phagocytosis may be the cause of the rupture of the gametocysts in this species.

Life history of Mysis stenolepis Smith (Crustacea, Mysidacea)

1975 ◽  
Vol 53 (7) ◽  
pp. 942-952 ◽  
Author(s):  
T. Amaratunga ◽  
S. Corey
Keyword(s):  
Young Adults ◽  
Life History ◽  
New Brunswick ◽  
Shallow Water ◽  
Field Study ◽  
Sexual Maturity ◽  
Developmental Stages ◽  
Shallow Waters ◽  
Passamaquoddy Bay ◽  
History Of

A 17-month field study showed that Mysis stenolepis in Passamaquoddy Bay, New Brunswick lives for about 1 year. Young are released in shallow water early in spring and grow rapidly during the summer. In the fall, young adults migrate to deeper water where they reach sexual maturity. Transfer of sperm lakes place during winter in deeper regions of the Bay. soon after which the males die. Females survive and in spring migrate to shallow waters to release young after which they die. Females breed once and carry an average of 157 young per brood. Developmental stages of the postmarsupial young are described and discussed.

scholarly journals Evolution of morphological and climatic adaptations inVeronica L.(Plantaginaceae)

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2333 ◽  
Author(s):  
Jian-Cheng Wang ◽  
Bo-Rong Pan ◽  
Dirk C. Albach
Keyword(s):  
Life History ◽  
Substitution Rate ◽  
Parallel Evolution ◽  
Morphological Characters ◽  
Annual Species ◽  
Selective Pressures ◽  
History Of ◽  
Phylogenetic Perspective ◽  
Drought Resistant ◽  
Annual Life History

Perennials and annuals apply different strategies to adapt to the adverse environment, based on ‘tolerance’ and ‘avoidance’, respectively. To understand lifespan evolution and its impact on plant adaptability, we carried out a comparative study of perennials and annuals in the genusVeronicafrom a phylogenetic perspective. The results showed that ancestors of the genusVeronicawere likely to be perennial plants. Annual life history ofVeronicahas evolved multiple times and subtrees with more annual species have a higher substitution rate. Annuals can adapt to more xeric habitats than perennials. This indicates that annuals are more drought-resistant than their perennial relatives. Due to adaptation to similar selective pressures, parallel evolution occurs in morphological characters among annual species ofVeronica.

scholarly journals Larval morphology and life history of Eutrichosoma mirabile Ashmead and description of a new species of Eutrichosoma (Hymenoptera, Chalcidoidea)

2020 ◽  
Vol 75 ◽  
pp. 67-85
Author(s):  
Austin J. Baker ◽  
John M. Heraty
Keyword(s):  
Life History ◽  
New Species ◽  
Morphological Characters ◽  
Larval Morphology ◽  
Phylogenetic Placement ◽  
History Of ◽  
A New Species

The larval morphology and life history of the weevil parasitoid Eutrichosoma mirabile Ashmead (Hymenoptera, Chalcidoidea, Pteromalidae) are described, and the phylogenetic placement of the subfamily Eutrichosomatinae within Chalcidoidea is determined using larval morphological characters. A description of Eutrichosoma burskisp. nov. and key to the species of Eutrichosoma are provided.

Revision of the Madagascan genera Oncodopus Brongniart and Colossopus Saussure (Orthoptera: Tettigoniidae: Conocephalinae; Euconchophorini), with description of Malagasopus gen. nov.

Zootaxa ◽  
2017 ◽  
Vol 4341 (2) ◽  
pp. 193 ◽  
Author(s):  
MUSTAFA ÜNAL ◽  
GEORGE W. BECCALONI
Keyword(s):  
Life History ◽  
New Species ◽  
Phylogenetic Relationships ◽  
New Genus ◽  
Habitat Preferences ◽  
Mate Guarding ◽  
Morphological Characters ◽  
Museum Specimens ◽  
History Of

The endemic Madagascan genera Oncodopus Brongniart and Colossopus Saussure are revised using museum specimens, including the types, and recently collected material. A new genus, Malagasopus gen. nov., and seven new species, Malagasopus desutterae sp. nov., Malagasopus meridianus sp. nov., Oncodopus janetae sp. nov., Oncodopus brongniarti sp. nov., Oncodopus saussurei sp. nov., Oncodopus soalalaensis sp. nov. and Colossopus parvicavus sp. nov. are described. Lectotypes are designated for Oncodopus zonatus Brongniart, 1897 and Colossopus redtenbacheri (Brongniart, 1897). A new term, mesothoracic auricle, is proposed for a structure on the episternum of the mesothorax. A tabulated key to the genera and keys to the species are presented. All species are described and diagnosed, and their phylogenetic relationships, geographical distributions, habitat preferences and phenologies are documented. The life history of Colossopus grandidieri is described, and the unusual possible mate-guarding behaviour of several species is discussed. Maps showing the distribution of the species are presented, as too are 57 photographs of museum specimens, 51 drawings of morphological characters, 17 photographs of living specimens and one habitat photograph. 

scholarly journals Life history of Tendaguru sauropods as inferred from long bone histology

Fossil Record ◽  
1999 ◽  
Vol 2 (1) ◽  
pp. 103-112 ◽  
Author(s):  
P. M. Sander
Keyword(s):  
Life History ◽  
Body Size ◽  
Sexual Dimorphism ◽  
Sexual Maturity ◽  
Upper Jurassic ◽  
Bone Histology ◽  
Long Bone ◽  
Large Mammals ◽  
Growth Series ◽  
History Of

Abstract. Sauropod dinosaurs present exceptional challenges in understanding their biology because of their exceptional body size. One of these, life history, can be inferred from the histology of their bones. For this purpose, the diverse sauropod assemblage of the Upper Jurassic Tendaguru beds was sampled with a new coring method which provided unprecented access to and insights into sauropod bone histology. Growth series of humeri and femora as well as long growth records from single bones suggest that all four sauropod taxa are characterized by continued growth after sexual maturity but that growth was determinate. Fibrolamellär bone is dominant in the samples, indicating that the bones of the Tendaguru sauropods grew at rates comparable to those of modern large mammals. The growth pattern of these sauropods thus combines typically reptilian traits with typically mammalian traits. In the details of their bone histology, the Tendaguru sauropod taxa show considerable variation which reflects life history. In addition, Barosaurus exhibits probable sexual dimorphism in bone histology. Das Verständnis der Biologie der sauropoden Dinosaurier wird durch ihre enorme Körpergröße außerordentlich erschwert. Allerdings kann ein Aspekt, die Lebensgeschichte, anhand der Histologie ihrer Knochen untersucht werden. Zu diesem Zweck wurde die diverse Sauropoden-Vergesellschaftung der oberjurassischen Tendaguru-Schichten beprobt, und zwar mit einer neuartigen Kernbohrmethode, die einen herausragenden Zugang und Einblick in die Knochenhistologie der Sauropoden ermöglichte. Wachstumsserien von Humeri und Femora sowie umfassende Überlieferungen des Wachstums von Individuen anhand einzelner Knochen machen es wahrscheinlich, daß alle vier Sauropoden-Taxa der Tendaguru-Schichten durch ein auch nach der Geschlechtsreife anhaltendes Wachstum gekennzeichnet waren. Allerdings ging das Wachstum nicht bis zum Tode des Tieres weiter, sondern kam bei einer etwas variablen Maximalgröße zum Stillstand. Fibrolamellärer Knochen ist der vorherrschende Knochentyp in den Proben, was anzeigt, daß die Tendaguru-Sauropoden mit für Säugetieren typische Raten wuchsen. Die Tendaguru-Sauropoden kombinerten also ein für Reptilien typisches Muster des Wachstums, nämlich nach der Geschlechtsreife anhaltendes Wachstum, mit für Säuger typischen Raten des Wachstums. Die verschiedenen Sauropoden-Taxa zeigen erstaunliche Unterschiede in den Details ihrer Knochenhistologie, die Unterschiede in der Lebensgeschichte belegen. Bei Barosaurus scheint außerdem ein Geschlechtsdimorphismus in der Histologie der Langknochen vorzukommen. doi:1002/mmng.1999.4860020107

Aspects of the life history of Meganyctiphanes norvegica (M. Sars), Crustacea (Euphausiacea), in Passamaquoddy Bay

1974 ◽  
Vol 52 (4) ◽  
pp. 495-505 ◽  
Author(s):  
K. W. Hollingshead ◽  
S. Corey
Keyword(s):  
Life History ◽  
Life Span ◽  
Sexual Maturity ◽  
Gonadal Development ◽  
Age Group ◽  
Group I ◽  
Passamaquoddy Bay ◽  
History Of ◽  
Meganyctiphanes Norvegica ◽  
First Time

Monthly collections of Meganyctiphanes norvegica for a 19-monih period in Passamaquoddy Bay showed that these euphausiids were present in the bay in varying numbers from February to November but virtually disappeared in December and January. Sexual maturity is attained in 1 year with gonadal development taking 3 months, and spawning occurring in July and August. The resulting generation will breed and spawn for the first time the next July as age group I. Age group I grows from April until August; from September until March, very little growth occurs. After a second breeding and spawning, the animals die, having a life span of 2 years.

The Life-history and Growth of the Cockroach Blatta orientalis, Linn.

1938 ◽  
Vol 29 (3) ◽  
pp. 263-276 ◽  
Author(s):  
M. A. H. Qadri
Keyword(s):  
Life History ◽  
Male Genitalia ◽  
External Genitalia ◽  
Special Care ◽  
Third Generation ◽  
Blatta Orientalis ◽  
The Third ◽  
Embryonic Growth ◽  
History Of

The life-history of Blatta orientalis has been studied from the time of the deposition of the ootheca by the female till the nymphs of the third generation emerge, viz., through two embryonic and one post-embryonic lives.The cockroach passes through one pronymphal and six nymphal stages and moults seven times after its exit from the ootheca.The post-embryonic growth, including the increase of the antennal and cercal joints, and the modification of the external genitalia, is described. It has been shown that nymphs of various instars and their sexes can be distinguished, especially with the help of the genitalia, the number of cercal joints, and the growth of the wing-rudiments.The average time taken by 27 nymphs to mature at 27·5C. is 279 days. The males mature earlier than the females and also die before the latter.The formation and structure of the spermatophore are described and also the exact mode of copulation, including the use of various parts of the male genitalia.The ootheca is deposited with special care by the female in that she digs a pit with the help of her mandibles and the fore legs and covers the ootheca afterwards. The nymphs emerge without the help of the female and the latter does not take any care of the ootheca after it has been safely deposited.

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