Reproduction in Gammarus (Crustacea, Amphipoda): basic processes

Research on the basic reproduction processes of Gammarus is summarized and reviewed, reproductive strategies in males and females being left to two later papers. The author describes the reproductive systems, the development of eggs (oocytes) in the ovaries, courtship and precopulatory amplexus, mating and the production of sperms, egg laying, mortality and diapause

Verwantskapsbepaling in die Dierkunde

Dit is ’n voorveronderstelling van alle natuurwetenskaplike navorsing dat dienatuur, waarvan die mens ook ’n deel uitmaak, nie ’n chaos nie maar ’n ordelikegeheel is. Hierdie ordelikheid word nie deur die mens in die natuur ingedra niemaar kan slegs broksgewys deur waarneming en navorsing uit die natuur geabstraheerword

Reproduction in Gammarus (Crustacea, Amphipoda): female strategies

This paper attempts to review the literature on Gammarus and examine how it allocates its internal resources when producing eggs. There is an extensive literature on the fecundity of freshwater species but almost nothing is known about the sizes and energy contents of the eggs. More is known for saltwater species, in which the mean number of eggs per brood is inversely proportional to mean egg size and directly proportional to the female's body size. Theoretical aspects of egg size, numbers and reproductive effort are examined, along with the relation between sizes of eggs, broods and female body size. The reproductive effort and breeding cycles of both saltwater and freshwater species are reviewed, and reproductive strategies assessed

Bylaag tot ,,Koers": Die taak, grondslag en terrein van die plantfisiologie, met spesiale verwysing na plantfisiologiese navorsing.

Die natuurwetenskappe is vroeër in twee groepe ingedeel, nl. die verklarende en die beskrywende wetenskappe. Onder eersgenoemde groep het die Fisika en die Skeikunde geressorteer, terwyl die Geologie, die Plantkunde en die Dierkunde onder laasgenoemde groep geplaas is

A checklist of the marine Harpacticoida (Copepoda) of the Caribbean Sea

Recent surveys on the benthic harpacticoids in the northwestern sector of the Caribbean have called attention to the lack of a list of species of this diverse group in this large tropical basin. A first checklist of the Caribbean harpacticoid copepods is provided herein; it is based on records in the literature and on our own data. Records from the adjacent Bahamas zone were also included. This complete list includes 178 species; the species recorded in the Caribbean and the Bahamas belong to 33 families and 94 genera. Overall, the most species family was the Miraciidae (27 species),followed by the Laophontidae (21), Tisbidae (17), and Ameiridae (13). Up to 15 harpacticoid families were represented by one or two species only. Excluding the Bahamian records, the number of species recorded herein for the Caribbean Basin is 139. The distribution of the species richness within the Caribbean Basin is asymmetrical; the northwestern sector (Mexican Caribbean) is the most species, it concentrates up to 45% of the species recorded in the Caribbean. The insular Caribbean is nearly as diverse as the continental areas (75 vs 83 species recorded, respectively). The dominance of taxa related to coastal systems with coarse and fine sands and carbonatesediments reveals the general trend in the type of habitats surveyed in the Caribbean Sea. Up to 37 species found in the Mexican Caribbean represent new records for this country. There are enormous hiatuses in the knowledge of the Caribbean harpacticoids in terms of geographic, bathymetric, and environmental coverage. It is expected this list will grow rapidly and many undescribed forms will be discovered when understudied or unexplored environments are surveyed in detail

Description of a new genus and species of Candonopsini (Crustacea, Ostracoda, Candoninae) from the alluvial valley of the Upper Paraná River (Brazil, South America)

The genus Candobrasilopsis gen. nov. is here described, with C. rochai gen. nov. sp. nov. as type species, from the alluvial valley of the Upper Paraná River. The enigmatic Candonopsis brasiliensis Sars, 1901 is here redescribed and transferred to this new genus, the new combination being Candobrasilopsis brasiliensis (Sars, 1901). The new candonid genus belongs to the tribe Candonopsini, because of the absence of the proximal seta on the caudal ramus. It is closely related to Latinopsis Karanovic & Datry, 2009, because of the relatively short terminal segment of the mandibular palp (length less than 1.5 times the basal width, while this segment is longer than three times the basal width in Candonopsis) and the large and stout b-seta on the T1. However, it differs markedly from Latinopsis in the size and shape of the calcified inner lamellae of both valves and in the type of hemipenis. We also discuss the doubtful allocation of several other genera to the Candonopsini, raise Abcandonopsis Karanovic, 2004 to generic status and reassess the uncertain position of Candonopsis anisitsi Daday, 1905 within Latinopsis

<i>Laophontopsis</i> Sars and the taxonomic concept of the Normanellinae (Copepoda: Harpacticoida): a revision

The taxonomic concept of the subfamily Normanellinae Lang (Harpacticoida, Laophontidae) is revised. As a result a new family Laophontopsidae is proposed to accommodate Laophontopsis Sars and two new genera Aculeopsis and Telodocus. It is concluded that the presumed boreo-mediterranean distribution pattern displayed by the type species L. lamellifera (Claus) is merely the result of erroneous identifications. The population of northwest Europe is assigned to a new species L. borealis and another new species L. monardi is proposed for Monard's (1928) material from Banyuls-sur-Mer. L. secundus Sewell is placed in the new genus Telodocus. Aculeopsis gen. nov. embraces only A. longisetosa spec. nov. and constitutes the most primitive genus of the family. The Laophontopsidae are placed within the superfamily Laophontoidea. The Normanellinae are provisionally upgraded to family level despite their diphyletic status because this narrows the diagnosis of the Laophontidae considerably. The genera are attributed to two clearly defined but non-related subfamilies, Normanellinae Lang (Normanella Brady) and Cletopsyllinae subfam. nov. (Cletopsyllus Willey, Pseudocletopsyllus Vervoort). The genus Pseudocleta Lang is relegated to incertae sedis within the Laophontoidae

Two new genera of Laophontidae (Copepoda: Harpacticoida) without sexual dimorphism in the endopods of the swimming legs

Two new monospecific genera of the harpacticoid family Laophontidae T. Scott, 1905 are described here. Apistophonte wasiniensis gen. et sp. n. was found along the Kenyan coast and Propephonte duangitensis gen. et sp. n. along the northern coast of Papua New Guinea. They differ from most other laophontid genera in the absence of sexual dimorphism in the endopods of the swimming legs. At first sight, both new species resemble each other very closely in habitus, integumental ornamentation, chaetotaxy of the swimming legs and absence of sexual dimorphism in the endopods. However, the detailed characteristics of A1, maxilla and male P5 show that the species are not congeneric. The structure of the first antennular segment of Propephonte gen. n. suggests a close relationship with Peltidiphonte Gheerardyn and Fiers, 2006. The exact affinities of Apistophonte gen. n. however remain difficult to assess

Re-description of Strandesia sanoamuangae Savatenalinton & Martens, 2010 and description of a new species of Strandesia (Crustacea, Ostracoda) from Grande Terre, New Caledonia

The New Caledonian Archipelago is a hot spot for biodiversity and endemism. Whereas popular groups such as birds and plants are well-studied, invertebrate groups such as ostracods remain ill-known. Here, we re-describe Strandesia sanoamuangae Savatenalinton & Martens, 2010, originally described from Thailand (8000 km away from New Caledonia), and describe Strandesia mehesi sp. nov. Both species are known only from females. Material for the present study was collected from diverse aquatic non-marine habitats from Grande Terre, the main island of New Caledonia. Whereas S. sanoamuangae is seemingly easily identifiable, S. mehesi sp. nov. is part of the Strandesia vinceguerrae/vavrai species cluster in the genus, of which the 'older' species (described long ago) often have incomplete and superficial descriptions. Differentiation between the new species and the other members of this species cluster are based on small anatomical details of the valves. The current paper updates the known number of recent freshwater Ostracoda of New Caledonia from 14 to 16 species, although at least five of these species have an uncertain status