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EN
The microalga Dunaliella has been the focus of attention over recent decades owing to its high biotechnological potential for the production of β-carotene, biofuels and even as a good expression system for the production of recombinant proteins. Different species of this genus have unique features, biological characteristics and biotechnological potential. Therefore, it is necessary to have a clear and reliable taxonomic method to identify different species of Dunaliella. Although several taxonomic systems are available for Dunaliella based on morphological, physiological and molecular features, none of these methods are reliable enough and some controversies exist over different classification systems. In the current study, molecular techniques and bioinformatics tools have been used to re-assess the phylogenetic position of Dunaliella species based on 18S ribosomal DNA (18S rDNA), ITS and rbcL regions. The overall findings based on these markers provide a new and more reliable tool for phylogenetic analysis of Dunaliella species/strains.
EN
The Family Neokoninckophyllidae and its type genus Neokoninckophyllum Fomichev, 1939 (type species: N. tanaicum Fomichev, 1939) are discussed and emended. In addition, the genera Orygmophyllum Fomichev, 1953 and Yuanophylloides Fomichev, 1953, originally included in the Families Campophyllidae Wedekind, 1922 and Lophophyllidae Grabau, 1928, respectively, are emended as well and transferred to the Neokoninckophyllidae. Two early Bashkirian species, viz. Yuanophylloides rectus (Vassilyuk in Aizenverg et al., 1983) and Y. inauditus (Moore and Jeffords, 1945), and the Moscovian Neokoninckophyllum sp. nov. are described on the basis of new collections from the Donets Basin. Neokoninckophyllum tanaicum, Yuanophylloides gorskyi Fomichev, 1953 (both Moscovian in age) and Y. cruciformis Fomichev, 1953 (latest Bashkirian), are redescribed on the basis of peels taken from Fomichev’s (1953) type specimens. Derivation of the Family Neokoninckophyllidae from the Subfamily Dibunophyllinae Wang, 1950 is postulated and phylogenetic links within the former are hinted at. The occurrence of Yuanophylloides inauditus in both the Donets Basin and the Western Interior Province of North America points to marine communication between those areas during the Bashkirian. The slightly earlier appearance of the oldest neokoninckophyllids in the Donets Basin, in comparison to North America (i.e., R1 vs R2 ammonoid biozones), documents the common roots and monophyletic development of the Neokoninckophyllidae in both areas.
EN
Seven genera (one new), belonging to four subfamilies, seven named species (six new), four species left in open nomenclature and two specimens included in this paper as unnamed Aulophyllidae are described from strata ranging from the lowermost Bashkirian Limestone D510 to the lower Bashkirian Limestone F1. A new genus: Voragoaxum and six new species: Dibunophyllum medium, Dibunophylloides columnatus, D. paulus, D. similis, Voragoaxum cavum and Rozkowskia lenta are introduced. Comparison of the ontogeny of the earliest Bashkirian species of Nina Fedorowski, 2017a and Dibunophylloides Fomichev, 1953 suggest the derivation by descent of the Family Bothrophyllidae from the Subfamily Dibunophyllinae. This means that true bothrophylla are absent in the Mississippian strata of the Western European Province and, perhaps, in the contemporaneous strata of other areas as well.
EN
The fossil record of the Coleorrhyncha goes back to the Upper Permian. In recent faunas only members of the Peloridiidae are present, restricted in distribution to the Southern Hemisphere. These insects were more diversified in the past, and though their fossil record in the Jurassic is restricted to the Northern Hemisphere, it comprises the families Progonocimicidae and Karabasiidae. The subfamily ­Progonocimicinae, present in the Jurassic strata of Europe and Asia is a declining lineage. The subfamily Cicadocorinae originated at the Triassic/Jurassic boundary and became dominant during Jurassic times. A review of Coleorrhyncha from European fossil sites is given, with taxonomic and phylogenetic problems highlighted. Their occurrence is linked to a very humid and warm climate, which is in agreement with independent data indicating greenhouse conditions in the atmospheric system and anoxia in the oceans at that time (Toarcian-Oceanic Anoxic Event – T-OAE) and coeval greenhouse climate on land. A new genus and species of the Progonocimicinae – Indutiono­marus treveriorum gen. et sp. nov. is described, based on a specimen from the Lower Toarcian of Bascharage, Luxembourg, Western Europe. It is the first record of the Coleorrhyncha from this locality. The morphological features of the new genus in respect to other ­Progonocimicidae, and its phylogenetic importance, are discussed. Mesoscytina anglica Yu. Popov, Dolling et Whalley, 1994 is transferred to the genus Mesocimex, resulting in Mesocimex anglicus (Yu. Popov, Dolling et Whalley, 1994) comb. nov.
EN
An extensive collection of ammonites made bed by bed from sections in the Submediterranean Upper Oxfordian of the Wieluń Upland, Central Poland, is described and used as a basis for a chronostratigraphical interpretation of the deposits. The ammonites are mostly of Submediterranean character and enable the recognition of the Bimammatum Zone, including the Bimammatum and Hauffianum subzones, as well as the lowermost Planula Zone distinguished here as a new biostratigraphical horizon – the matyjai horizon – based on the occurrence of Subnebrodites matyjai Wierzbowski et Głowniak sp. nov. The Submediterranean ammonites are mostly oppeliids with Taramelliceras (Taramelliceras) [M] – Glochiceras (Lingulaticeras) [m] the most numerous, as well as Taramelliceras (Richeiceras) and Taramelliceras (Metahaploceras) [M] – Glochiceras (Coryceras) [m]. The profusion of ammonites of these two groups in the stratigraphical interval studied provides new information on their evolution, and two new oppeliid species, Taramelliceras (Taramelliceras) zelcense Wierzbowski et Głowniak sp. nov. and Glochiceras (Lingulaticeras) bobrownikiense Wierzbowski et Głowniak sp. nov., are described here. Subboreal and Boreal ammonites are not common in these sections, but are nevertheless important for correlation. Subboreal ammonites of the family Aulacostephanidae are represented by the genus Vineta [M], including its newly recognized microconchiate counterpart, Vineta [m], and a newly established genus Vielunia [M] Wierzbowski et Głowniak gen. nov., with type species Vielunia dzalosinensis Wierzbowski et Głowniak sp. nov. The latter genus includes ammonites previously referred in the area of study to Ringsteadia, and with a microconchiate counterpart assigned to Prorasenia [m]. The Boreal ammonites comprise late cardioceratids assigned to Amoeboceras (Plasmatites). These ammonites indicate that the deposits in question from the Submediterranean Bimammatum Zone up to the Planula Zone correlate with the Subboreal and Boreal lowermost Kimmeridgian (Baylei Zone, and Bauhini Zone, respectively).
EN
The ammonoid "Trachyphyllites costatum" Arthaber (1927), based on a single specimen from an erratic boulder of presumed Late Triassic (Norian age) from Timor, (Indonesia), was originally described as a phylloceratid but later recognized as a true lytoceratid by Basse (1952) and Schindewolf (1961), and used by Wiedmann (1966a, 1966b, 1970) to support his idea of a polyphyletic origin of the post-Triassic ammonoids and of the Late Triassic roots of the lytoceratids. New collections of additional specimens and associated taxa from other erratic boulders in the type locality have confirmed observations (Tozer 1971; Krystyn 1978) that the age of the original boulder was misinterpreted, and have shown that "Trachyphyllites" is actually of Early Jurassic (Hettangian) age. An unpublished generic revision of the entire superfamily Lytoceratoidea by Hoffmann (2009) has shown that "Trachyphyllites costatum Arthaber" is a junior synonym of Analytoceras hermanni (Gumbel, 1861), a taxon thought by Wahner (1894) to be a subjective synonym of Analytoceras articulatum (J. Sowerby, 1831) We reestablish the species Analytoceras hermanni (Gumbel, 1861) for Analytoceras articulatum "Type B" (Wahner 1894), which is characterized by a wide umbilicus and a small whorl expansion rate. The morphologically distinct "Type A" (Wahner 1894) corresponds to the type species of Analytoceras, A. articulatum (J. Sowerby, 1831). A revised phylogeny of the Early Jurassic lytoceratids is presented.
EN
As many hybodont sharks are known solely from their teeth, this investigation approaches the phylogeny of the group with an emphasis on tooth morphology and dentitional patterns. The preliminary results presented here suggest that at least four different lineages of hybodont sharks occurred in the Mesozoic. Dentitional characters imply a close relationship within the Lonchidiidae (Lonchidion, Vectiselachos, Parvodus, and tentatively Hylaeobatis), within the Hybodontinae (Hybodus and Egertonodus) and in another, unnamed subfamily of the Hybodontidae, including Planohybodus, Secarodus and Priohybodus. There is also weak support for a grouping of Acrodus, Asteracanthus and Palaeobates in the Acrodontinae, while Lissodus is left without family designation due to a rather unique dentition and cephalic spine morphology. "Polyacrodus" is considered a nomen dubium as there are no characters to diagnose the genus based on the type species.
8
Content available remote A Low-complexity Distance for DNA Strings
EN
We exhibit a low-complexity but non-trivial distance between strings to be used in biology. The experimental results we provide were obtained on a standard laptop and, even if preliminary, are quite encouraging.
EN
Similarities between scleractinian corals from extinct suborders Pachythecaliina Eliášová 1976 and Rhipidogyrina Roniewicz 1976 are discussed. Corals of the former suborder are considered by some authors as possible descendants of Palaeozoic Rugosa because of their unusual skeletal characters. Some rhipidogyrinans, especially the family Aulastraeoporidae, despite their different septal microstructure, share more common features with pachythecaliinans than with other scleractinians. The following skeletal features are discussed to show similarities between these two suborders: (1) wall microstructure and its relations to septa, (2) corallite bilateral symmetry, (3) marginarium, (4) lonsdaleoid and apophysal septa, and (5) internal septal margin. These similarities can be explained by convergence, although phylogenetic relationships of both suborders can not be excluded. This hypothesis needs to be verified by more studies, especially on early blastogeny of rhipidogyrinans and wall microstructure of pachythecaliinans. The systematic part gives descriptions of the discussed coral suborders occuring in the Štramberk-type limestones, the Polish Outer Carpathians (Tithonian-?Berriasian, ?Valanginian). Similarly as in the Štramberk Limestone (Moravia), pachythecaliinans are highly diversified (17 species, 12 genera, including Pachythecophyllia eliasovae n.gen., n.sp.). Rhipidogyrinans are represented by 4 species of 4 genera, including ?Ogilvinella morycowae n.sp.
EN
The Plicatilis Zone of the Submediterranean Middle Oxfordian is redefined and subdivided into three subzones; the Paturattensis Subzone, the Ouatius Subzone and the Arkelli Subzone. Their boundaries are defined by the appearance of the successive perisphinctid species referred to a Kranaosphinctes-Otosphinctes lineage. Correlation with other lower Middle Oxfordian zonations is provided. Classification of the studied ammonites is based on the morphological variability in the successive perisphinctid assemblages. The species are assigned to three genera: Perisphinctes, Liosphinctes and Neumannia gen. nov. Microconchs of Neumannia gen. nov. and of Perisphinctes trifidus (SOWERBY) are described for the first time. The type species of the subgenus Arisphinctes, P. ariprepes (BUCKMAN) is reassigned to the subgenus Kranaosphinctes BUCKMAN, and thus Arisphinctes is treated as a younger synonym of Kranaosphinctes; Perisphinctes plicatilis (SOWERBY) and Perisphinctes laevipickeringius ARKELL are reinterpreted and reassigned to the genus Liosphinctes BUCKMAN. Two new chronosubspecies, Perisphinctes ouatius ouatoides and Perisphinctes arkelli wysokae of the subgenus Otosphinctes, are described. The Kranaosphinctes-Otosphinctes lineage gives rise to the Perisphinctes-Dichotomosphinctes lineage at the boundary between the Plicatilis and Transversarium zones. The two other lineages, one of P. trifidus (a possible offshoot from the Kranaosphinctes-Otosphinctes lineage), and the other of the genus Liosphinctes, disappear in the upper Arkelli Subzone of the Plicatilis Zone. Mediterranean roots for all of the three lineages are suggested. The fourth lineage, of Neumannia gen. nov., appears in the upper Arkelli Subzone of the Plicatilis Zone as a consequence of an immigration event from the Mediterranean area.
11
Content available remote Ecological characteristic of rare species : the case of parasitic hymenoptera
EN
Ecological characteristic of relatively rare (singleton) hymenopteran species sampled in a beech forest on limestone are studied. No marked differences between singleton and non-singleton species occurred in regard to guild membership, stratum of host attack and phenology. There was however a strong effect of sample size on the fraction of singletons. Body size and phylogenetic position also appeared to influence rarity, but it proofed to be difficult to separate the effects of both variables. Rare species appeared to have larger density fluctuations but - in line with the theory of local mate competition - lover sex rations than more common species. Brachypterous and apterous species had lower fractions of singletons. This result contradicts theoretical expectations of metapopulation models.
EN
A combination of methods from cladistics and stratophenetic analyses is used for a reconstruction of Early and Middle Devonian ammonoid phylogeny. The analyses are based mainly on principal characters such as conch geometry (coiling form, whorl expansion rate, whorl cross-section shape), septal geometry (form of septa, number, position, and shapes of lobes), and ornament (growth lines and ribs); a new classification scheme of the ancient ammonoid order Agoniatitida is proposed. It is subdivided into four suborders: Agoniatitina (paraphyletic), Gephuroceratina (monophyletic), Anarcestina (paraphyletic), and Pharciceratina (monophyletic). Morphometric analysis shows the unfolding of several morphological trends, such as the modification of coiling parameters, among the Early and Middle Devonian ammonoids. Two major independent lineages can be recognised in the phylogeny of the Middle Devonian ammonoids, the first represents the agoniatids in which the Gephuroceratina is nested, the second are the anarcestids which gave rise to the Pharciceratina. The new families Latanarcestidae, Tamaritidae, Atlantoceratidae, and Taouzitidae, as well as the new genera Taouzites, Croyites and Meragoniatites are introduced.
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