| 1. |
- Chakma, Sanjib, et al.
(författare)
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Preliminary report on freshwater oligochaetes from some districts of Tamil Nadu (India), along with DNA barcode sequence of a commercially important oligochaete in Chennai
- 2020
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Ingår i: Zoosymposia. - : Magnolia Press. - 1178-9905 .- 1178-9913. ; 17, s. 45-52
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Tidskriftsartikel (refereegranskat)abstract
- A survey of aquatic Oligochaeta was conducted at Thiruvallur, Chennai, Kanchipuram, Villupuram and Nilgiris districts of Tamil Nadu from October 2015 to June 2016. Eleven taxa were recorded from a total of 922 specimens examined, eight of them were identified to species level. Five naidids identified during the present study: Branchiodrilus semperi, Dero dorsalis, Dero digitata, Dero indica and Dero zeylanica, and six tubificid taxa Branchiura sowerbyi, Tubificidae sp. 1, Tubificidae sp. 2, Tubificidae sp. 3, Limnodrilus hoffmeisteri and L. udekemianus. Dero dorsalis constitute the first report for Kanchipuram district. A DNA barcode sequence (GenBank accession no. MF125273) of the commercially important Limnodrilus hoffmeisteri, commonly known as ‘Tubifex worms’ in Chennai, was obtained and compared with other published COI sequences from that morphospecies from around the world.
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| 2. |
- Johanson, Kjell Arne, 1966-, et al.
(författare)
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New Caledonia's Trichoptera—present status of knowledge
- 2019
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Ingår i: Zoosymposia. - Mapress : Magnolia Press. - 1178-9905 .- 1178-9913. ; 14, s. 87-102
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Tidskriftsartikel (refereegranskat)abstract
- The first Trichoptera recorded from New Caledonia were four species described by Kimmins in 1953, each in anew endemic genus. The diversity was increased to eight species with the publication by Sykora in 1967 of threenew species in two new genera and a fourth species in a previously established genus. Today, 239 valid species areknown from the country, representing 20 genera in 10 families. Analysis of published records for some 32,000Trichoptera specimens collected from 291 localities shows that the highest species diversity is in the SE part of theGrande Terre, and that species diversity is greatest at lower altitudes, i.e. 0–200 meters above sea level. We also seethat the three most frequently collected families (85% of the individuals) in the sampled material are Hydroptilidae(35%), followed by Hydropsychidae (27%), and Leptoceridae (22%). Phylogenetic analyses have demonstratedthat the first species to occupy the island and the earliest radiations took place on areas covered by ultrabasicsubstrate, which is poor in nutrients and rich in certain toxic heavy metals.
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| 3. |
- KROH, ANDREAS, et al.
(författare)
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On the spelling of Antrechinus nordenskjoldi (Echinodermata: Echinoidea)*
- 2012
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Ingår i: Zoosymposia. - : Magnolia Press. - 1178-9905 .- 1178-9913. ; 7:1, s. 241-245
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Tidskriftsartikel (refereegranskat)abstract
- The spelling of organism names seems to be a trivial matter. A brief glance at the scientific literature, however, shows that it is far from that. In some cases, delving into these seemingly minor or even unimportant issues of spelling can turn up historical information germane to our science. Apart from simple misspellings and printing errors, differing ideas about the formation of names and the late onset of regulations (ICZN, ICBN) covering the naming and use of names are sources for different spellings. It was not until 1905 that a first internationally accepted version of what we now know as “the Code” was published under the name “Règles internationales de la Nomenclature Zoologique adoptées par les Congrès Internationaux de Zoologie”. The Code kept being emended after this first attempt to provide a unified set of rules for the naming and treatment of names and today, for animals, the 4th edition of the Code is valid (ICZN 1999).
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| 4. |
- Schmelz, R. M., et al.
(författare)
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Astacopsidrilus hibernicus sp. nov. (Phreodrilidae, Oligochaeta, Annelida) from Irish peatlands
- 2020
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Ingår i: PROCEEDINGS OF THE 14TH INTERNATIONAL SYMPOSIUM ON AQUATIC OLIGOCHAETA. - : Magnolia Press. - 9781776708697 ; , s. 34-44
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The discovery of a large and flourishing population of Phreodrilidae in terrestrial peatlands in northwest Ireland was surprising on two counts: these oligochaete worms are usually aquatic and most of the species occur in the Southern Hemisphere. The phreodrilids were discovered in a project that targeted Enchytraeidae, therefore methods adapted to the investigation of enchytraeids could be applied, including the study of living animals and properly fixed whole mounts. DNA sequencing was also performed. All worms identified here belong to one species, new to science, and placed in the genus Astacopsidrilus, because of the ventral position of the spermathecal pores and the opening of the female funnels inside the spermathecal vestibule. Astacopsidrilus hibernicus sp. nov. is mainly distinguished by thick segmental cushions of epidermal gland cells on the dorsal side of the posterior body half. Male sexual organs and spermathecae are comparatively small and without the oftenobserved bizarre modifications common in species of this family. DNA sequencing yielded a fragment of the 16S rRNA gene. This is the first description of a phreodrilid species from Europe; the few previous recordings of this family in Ireland and the United Kingdom had been left unidentified.
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| 5. |
- Sonesten, Lars
(författare)
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Composition and abundance of oligochaetes in large Scandinavian lakes in a morpho-edaphic index framework—in the 1970s and 50+ years later
- 2023
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Ingår i: Zoosymposia. - 1178-9905 .- 1178-9913. ; 23, s. 41-51
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Tidskriftsartikel (refereegranskat)abstract
- Bottom-living oligochaetes and chironomid larvae, thanks to their supposedly integrative power, could provide more robust measures of the water quality of lakes than separate chemical data. The oligochaete fauna of the large lakes of southern Scandinavia has been studied in detail over many years—often 100 years or more (Milbrink, 2020). Characteristic species associations and the ecological preferences of each oligochaete species are thus relatively well-known. In Milbrink (2020) it was shown that the precision could be greatly improved if the relationship between oligochaete species and chemical data could be instead demonstrated within a morpho-edaphic index framework (Ryder et al. 1974). The percentage composition and total abundance of oligochaetes per sample in a number of large lakes or selected basins of large lakes in southern Sweden and Norway were thus tested against this index in the 1970s (Milbrink, 1978). The trophic change which had taken place in the oligotrophic Lake Vättern—first with eutrophication and later with oligotrophication—was illustrated graphically and discussed in this work (Milbrink, 2020). A very similar trophic change could also be seen in the oligotrophic Lake Vänern (the basin of Värmlandssjön), as well as in the more eutrophic Lakes Mälaren and Hjälmaren. All these large lakes, once eutrophied in the 1950s and 1960s, are today undergoing oligotrophication. We simply have a melioration thanks to advanced sewage treatment since the 1960s. With our new knowledge, it is informative studying changes in species composition after trophic change. In a time when efforts to save the environment often fail, this new development is a real success story
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| 6. |
- Stöhr, Sabine, et al.
(författare)
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Comparison of 2D SEM imaging with 3D micro-tomographic imaging for phylogenetic inference in brittle stars (Echinodermata: Ophiuroidea)
- 2019
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Ingår i: Zoosymposia. - : Magnolia Press. - 1178-9905 .- 1178-9913. ; 15, s. 146-158
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Tidskriftsartikel (refereegranskat)abstract
- Recent efforts to reconstruct the phylogeny of brittle stars (ophiuroids) have shown the need for more objective and reproducible data collection methods than the traditional visual examination and verbal description of morphological characters. Complex skeletal structures may be better understood in three dimensions than in two dimensions obtained from techniques like scanning electron microscopy (SEM). We test this hypothesis using three types of three-dimensional tomographic imaging methods—lab-based micro-CT, X-ray microscopy and synchrotron-based tomography—to examine the morphology of ophiuroid arms, and compare them with two-dimensional data obtained from SEM. We describe the advantages and disadvantages of each instrument and set of parameters in terms of the ease and efficiency of data collection for morphometric analyses. We present new morphological observations obtained by digital sectioning of three-dimensional images that could not be achieved with SEM. Overall, our findings suggest that three-dimensional imaging has a high potential to address the gaps in knowledge of the internal ophiuroid skeleton, which will be pivotal to providing morphological characters that will aid in phylogenetic reconstructions.
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| 7. |
- Stöhr, Sabine
(författare)
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Ophiuroid (Echinodermata) systematics—where do we come from, where do we stand and where should we go?*
- 2012
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Ingår i: Zoosymposia. - : Magnolia Press. - 1178-9905 .- 1178-9913. ; 7:1, s. 147-162
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Tidskriftsartikel (refereegranskat)abstract
- Over 2,000 Recent species of brittle star are currently known. The most active period of species discovery was between 1850 and 1950, with an average rate of about 20 new species per year, but even today, an average of 7 species per year are described. The most prolific authors were R. Koehler, H.L. Clark, T. Lyman, T. Mortensen and C. Lütken. Early classifications divided the Ophiuroidea into Euryalida and Ophiurida. Matsumoto suggested in 1917 further subdivision, accepted by some authors, rejected by others. His classification is still the most comprehensive work available. A first modern cladistic analysis was presented in 1995 by Smith et al., but despite its shortcomings, no further attempts at reconstructing the phylogeny of the whole class have been made. It is becoming increasingly clear that Ophiuroidea have undergone rapid evolution after the great extinction event at the Permian/Triassic boundary, complicating phylogenetic analysis both with morphological and molecular data. Palaeozoologists still debate which ophiuroid group(s) survived the extinction. It has been suggested that the modern families Ophiuridae and Ophiolepididae may be traced back to the Palaeozoic, but the traditional view puts Ophiacanthidae and Ophiomyxidae at the root of the tree, with Euryalida as ancient sister group to Ophiurida. Unusual species with aberrant traits abound, but are still poorly understood. New morphological approaches, such as the study of the internal skeleton (jaws, dental plates, lateral arm plates), ontogeny and the role of paedomorphosis, as well as the extensive use of SEM for microstructure examinations, attempt to improve our understanding of the diversity and evolution of brittle stars.
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| 8. |
- Wells, Alice, et al.
(författare)
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Micro-caddisfly faunas of Australia and the southwest Pacific(Trichoptera, Hydroptilidae)
- 2016
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Ingår i: Zoosymposia. - : Magnolia Press. - 1178-9905 .- 1178-9913. ; 10, s. 439-450
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Tidskriftsartikel (refereegranskat)abstract
- Today's distributions of faunal groups reflect historic events—geological and evolutionary, as well as dispersals, extinctionsand chance events. The extent to which each of these contributed to the hydroptilid faunas of mainland Australia,Tasmania, New Guinea, New Zealand, New Caledonia, Fiji and Vanuatu is explored by comparison of the faunal composition,geology and geography of Australia and these SW Pacific islands. Corroborative evidence is sought from othergroups, flora as well as fauna.
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| 9. |
- Wells, Alice, et al.
(författare)
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Why are so many species based on a single specimen?
- 2019
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Ingår i: Zoosymposia. - : Magnolia Press. - 1178-9905 .- 1178-9913. ; 14, s. 32-38
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Tidskriftsartikel (refereegranskat)abstract
- A considerable number of insect species, including Trichoptera, are described from a single specimen, also knownas a 'unique' or a 'singleton'. We ask the question of whether this reflects failure to consider variation and relatedspecies, lack of collecting effort, or true rarity. In an attempt to answer this question we examine the availableliterature and data on the Trichoptera of Tasmania and New Caledonia. We note a low level of taxonomicsynonymy among species in these faunas. Moreover, a significant proportion of species from Tasmania that werebased originally on singletons have been re-collected subsequently, but this is not true for New Caledonia. Thepossible significance of these figures is considered following examination of data on diversity and abundance ofHydroptilidae collected by regular, standardised light trapping over almost two years at a northern Australiantropical stream. We conclude that quite a large proportion of the Trichoptera species based on singletons are rare,valid species, but for others the appearance of rarity may be a consequence of inadequate collecting, particularbehavioural attributes of the species, including seasonality, and failure to consider fully the structural diversity ofrelated species. Lastly, we discuss briefly the consequences of rarity, apparent or real, on conservationmanagement.
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