Life-history, morphological variability and taxonomy of some chlorococcal algae (Chlorophyceae)

1978 ◽  
Vol 40 (2) ◽  
pp. 358-360 ◽  
Author(s):  
František Hindák
Keyword(s):  
Life History ◽  
Morphological Variability ◽  
Chlorococcal Algae

Comparison of growth physiology, morphology, and smolt indicators in juvenile Lake Superior brook trout (Salvelinus fontinalis) strains in reference to life history variation

2012 ◽  
Vol 69 (10) ◽  
pp. 1596-1609 ◽  
Author(s):  
Carla A.V. Serfas ◽  
Anna Varian ◽  
Rachel Holman ◽  
Lindsey M. Watch ◽  
Jesse Karner ◽  
...  
Keyword(s):  
Life History ◽  
Brook Trout ◽  
Salvelinus Fontinalis ◽  
Lake Superior ◽  
Morphological Variability ◽  
Life History Strategy ◽  
Growth Potential ◽  
Relative Mass ◽  
Life History Variation ◽  
Rate Condition

Lake Superior supports fluvial, adfluvial, and lacustrine populations of brook trout ( Salvelinus fontinalis ). Adfluvial and lacustrine populations (termed coasters) are known for their large size and are coveted by anglers; however, little is known about their migratory habits or physiology. This study examined physiology and morphology of age 1+ lacustrine, adfluvial, and fluvial strains of brook trout in a laboratory setting. All strains in the study grew; however, there were no differences in growth rate, condition, relative mass, morphology, white muscle metabolic enzymes, or gill Na+,K+-ATPase that clearly associated with putative life history strategy. Both thyroxine and triiodothyronine varied over the study period, and the fluvial (resident) strain consistently showed lower thyroid hormone levels than the three coaster strains. We conclude that the populations compared differed at the strain level, but do not show physiological or morphological variability that clearly associates with life history strategy; the exception was that populations demonstrating the coaster phenotype had increased concentrations of plasma thyroid hormones, which may be linked to growth potential or other coaster-related characteristics such as migration.

Life history, morphology and distribution of Dipolydora armata (Polychaeta: Spionidae)

2003 ◽  
Vol 83 (2) ◽  
pp. 375-384 ◽  
Author(s):  
Vasily I. Radashevsky ◽  
João M. Nogueira
Keyword(s):  
Life History ◽  
Asexual Reproduction ◽  
Morphological Variability ◽  
Extended Period ◽  
The Body ◽  
Mutualistic Symbiosis ◽  
Egg Capsules ◽  
History Of ◽  
Original Interpretation ◽  
First Time

The spionid polychaete Dipolydora armata, a borer in calcareous substrata, is recorded for the first time from Belize, Brazil, Taiwan, and Vietnam. Specimens from these and other localities, as well as the type material of Polydora armata from Madeira Island and Polydora rogeri from the Mediterranean were examined and all the specimens were considered to be conspecific. Dipolydora armata is up to 8 mm long (usually 2–3 mm), with up to 45 segments (usually 25–35 segments), an incised prostomium, caruncle until the end of segment 2, up to 10 pairs of branchiae from segment 7, up to 20 awl-like modified spines per notopodium in up to 15 posterior segments, bilobed or cup-shaped pygidium, hooded hooks from segment 7 accompanied by capillaries throughout the body, major falcate spines of segment 5 with a large lateral tooth and an apical structure covered by fine bristles and appearing as a cowling or third tooth on the convex side of the main fang.  The life history of the species includes a period of asexual reproduction by architomy beginning soon after settlement, then sexual maturation and continuous breeding within an extended period with production of lecithotrophic larvae developing entirely inside egg capsules. Once mature, individuals probably reproduce only sexually and do not undergo additional architomic divisions.  Asexual reproduction results in high morphological variability of adult individuals, particularly in number, size, and arrangement of awl-like spines in notopodia. Polydora rogeri is placed into synonymy of D. armata. The original interpretation of the relationship between the polychaetes and the excavating sponge Cliona viridis as mutualistic symbiosis is discussed. Dipolydora armata is considered to be a widespread non-specialized borer perforating various calcareous substrata.

scholarly journals Life history, morphological variability and growth rates of the life phases of Gracilaria tenuistipitata (Rhodophyta: Gracilariales) in vitro

2010 ◽  
Vol 74 (2) ◽  
pp. 297-303 ◽  
Author(s):  
José Bonomi Barufi ◽  
Eurico Cabral de Oliveira ◽  
Estela Maria Plastino ◽  
Mariana Cabral de Oliveira
Keyword(s):  
Life History ◽  
Growth Rates ◽  
Morphological Variability ◽  
Gracilaria Tenuistipitata

scholarly journals The Middle American species of Embates Chevrolat (Coleoptera: Curculionidae: Baridinae)

Zootaxa ◽  
2005 ◽  
Vol 1100 (1) ◽  
pp. 1 ◽  
Author(s):  
JENS PRENA
Keyword(s):  
Life History ◽  
New Records ◽  
Morphological Variability ◽  
Valid Species ◽  
Immature Stages ◽  
New Combinations ◽  
Line Drawings ◽  
New Synonyms ◽  
Plant Associations ◽  
Middle America

The neotropical weevil genus Embates Chevrolat is revised. New synonyms of Embates are Drepanambates Jekel, Batames Casey, Macrambates Casey and Cholinambates Casey. Information is provided about the morphology of the immature stages, life history, sexual dimorphism and morphological variability. A total of 69 species is recognized in Middle America, 38 of which are newly described here: E. aequiperabilis, E. aliquantulus, E. bicoctura, E. burgeri, E. callifer, E. chelys, E.clandestinus, E. consimilis, E. cordiger, E. crinipes, E. discissus, E. discordabilis, E. euchasma, E. euscheme, E. flavoplagiatus, E. galbinus, E. gilvopictus, E. gracilis, E. intermedius, E. kunicus, E. maculifer, E. marchionis, E. mendax, E. oculifer, E. paludicola, E. paucilimbatus, E. pauhans, E. peperomiae, E. politus, E. pseudobumbraticus, E. pullus, E. rutilus, E. sagittifolicus, E. scambus, E. subulirostris, E. terrabanicus, E. todillofasciatus and E. uniformis. Six new subspecies are described: E. polymorphus altrimsecus, E. polymorphus dotensis, E. polymorphus fortunensis, E. polymorphus tabulensis, E. polymorphus zeledonensis and E. leucopleura discolor. New combinations are E. belti (Champion), E. leucopleura (Champion) and E. flavolimbatus (Voss) [all from Drepanambates]. New synonyms are E. belti [= E. triangularis (Champion)], E. fasciolatus (Chevrolat) [= E. sexpunctatus (Champion)] and E. solani (Champion) [= E. divisus (Casey)]. Embates rugosus (Hustache) is distinguished from E. solani and resurrected as a valid species. New records for Middle America are E. flavolimbatus (Voss), E. justini (Chevrolat) and E. rugosus. Descriptions, line drawings of habitus and male genitalia, geographic distributions, plant associations and keys for identification are provided.

Four new species of Ursinia (Asteraceae, Anthemideae) from South Africa, with an updated key to the genus in Namaqualand

Phytotaxa ◽  
2014 ◽  
Vol 177 (3) ◽  
pp. 137 ◽  
Author(s):  
Anthony Richard Magee ◽  
JAMES S. BOATWRIGHT ◽  
LADISLAV MUCINA
Keyword(s):  
South Africa ◽  
Life History ◽  
New Species ◽  
Morphological Variability ◽  
African Genus

Recent field and herbarium studies of the southern African genus Ursinia (Anthemideae, Asteraceae) in Namaqualand, South Africa, have revealed greater morphological variability than currently accommodated and a high percentage of misidentified specimens. In an attempt to remedy this we herein describe four new species (Ursinia arida, U. glandulosa, U. kamiesbergensis and U. laciniata) and provide a key to the species in the region, together with illustrations of their involucral bracts and paleae. The species can be distinguished by a combination of their life history, vestiture, presence or absence of appendages on the paleae, and shape of the involucral bracts and their scarious apices.

Interrelationships of factors of social development are more complex than Life History Theory predicts

2019 ◽  
Vol 42 ◽  
Author(s):  
Boris Kotchoubey
Keyword(s):  
Life History ◽  
Social Development ◽  
Life History Theory ◽  
Strong Correlations ◽  
Behavioral Features

Abstract Life History Theory (LHT) predicts a monotonous relationship between affluence and the rate of innovations and strong correlations within a cluster of behavioral features. Although both predictions can be true in specific cases, they are incorrect in general. Therefore, the author's explanations may be right, but they do not prove LHT and cannot be generalized to other apparently similar processes.

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