Dendrogramma, new Genus, with two new non- bilaterian species from the Marine Bathyal of Southeastern Australia (Animalia, Metazoa incertae sedis) – with similarities to some medusoids from the precambrian ediacara

This study examines a new species of dinosaur named Dendrogramma, which has been found near Bass Strait. Abstract A new genus, Dendrogramma, with two new species of multicellular, non-bilaterian, mesogleal animals with some bilateral aspects, D. enigmatica and D. discoides, are described from the south-east Australian bathyal (400 and 1000 metres depth). A new family, Dendrogrammatidae, is established for Dendrogramma. These mushroom-shaped organisms cannot be referred to either of the two phyla Ctenophora or Cnidaria at present, because they lack any specialised characters of these taxa. Resolving the phylogenetic position of Dendrogramma depends much on how the basal metazoan lineages (Ctenophora, Porifera, Placozoa, Cnidaria, and Bilateria) are related to each other, a question still under debate. At least Dendrogramma must have branched off before Bilateria and is possibly related to Ctenophora and/or Cnidaria. Dendrogramma, therefore, is referred to Metazoa incertae sedis. The specimens were fixed in neutral formaldehyde and stored in 80% ethanol and are not suitable for molecular analysis. We recommend, therefore, that attempts be made to secure new material for further study. Finally similarities between Dendrogramma and a group of Ediacaran (Vendian) medusoids are discussed

Characterisation of chitin in the cuticle of a velvet worm (Onychophora)

*Kaya, Murat ( Aksaray, Yazar ) *Baran, Talat ( Aksaray, Yazar )We characterize the trunk cuticle of velvet worms of the Peripatoides novaezealandiae-group (Onychophora) using SEM, TEM, Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). TEM and SEM revealed a relatively uniform organization of the delicate cuticle that is covered by numerous bristled and nonbristled papillae with ribbed scales arranged in transverse rows. The cuticle consists of a very thin multilayered epicuticle of varying appearance followed by the largely fibrous procuticle. The irregularly arranged nanofibres of isolated cuticular chitin seen by SEM are considered as bundles of chitin fibres. FT-IR and TGA showed that the chitin is of the α-type. This confirms and broadens the single previous study in which the presence of α-chitin in a velvet worm was demonstrated with a single analysis (X-ray diffraction)...

Integrative taxonomy identifies Macrobiotus papei, a new tardigrade species of the Macrobiotus hufelandi complex (Eutardigrada : Macrobiotidae) from the Udzungwa Mountains National Park (Tanzania)

In this paper we describe Macrobiotus papei, a new species of the Macrobiotus hufelandi complex from the Udzungwa Mountains National Park in Tanzania. Our research included the traditional morphology-based taxonomic analysis, supported by morphometrics, light and scanning electron microscopy imaging, as well as analysis of nucleotide sequences of three nuclear (18S rRNA, 28S rRNA, ITS-2) and one mitochondrial (COI) marker. The molecular sequences provided a more accurate description and independent verification of the taxonomic status of M. papei sp. nov. Such integrative approach requires a considerable number of individuals and eggs, which we obtained by establishing a laboratory culture of the new species. Our analyses revealed that M. papei sp. nov., by having the flexible filaments on the terminal discs of the egg processes, is most similar to Macrobiotus paulinae Stec et al., 2015 from Africa and Macrobiotus polypiformis Roszkowska et al., 2017 from South America. However, the new species can be easily distinguished from both these species by patches of cuticular granulation on the external and internal surface of legs I–III (only external patches present in in M. paulinae and M. polypiformis), two separate lateral transversal ridges with a rounded median tooth between instead of a single thin ventral transverse ridge in the third band of teeth in the oral cavity, smooth terminal discs and filaments on the egg processes (terminal discs and filaments covered by aggregations of small microgranules in M. paulinae and M. polypiformis), and by some morphometric characters of both adults and eggs

Expression of synapsin and co-localization with serotonin and RFamide-like immunoreactivity in the nervous system of the chordoid larva of Symbion pandora (Cycliophora)

Cycliophora is one of the most recently described metazoan phyla and hitherto includes only two species: Symbion pandora and Symbion americanus. With a very complex life cycle, cycliophorans are regarded as an enigmatic group with an uncertain phylogenetic position, although they are commonly considered lophotrochozoan protostomes. In order to extend the database concerning the distribution of immunoreactive substances in the free-swimming chordoid larva of S. pandora, we investigated synapsin immunoreactivity using fluorescence-coupled antibodies in combination with confocal laserscanning microscopy. Moreover, we analyzed the co-localization patterns of synapsin, serotonin, and RFamide-like immunoreactivity in the chordoid larva by 3D imaging technology based on the confocal microscopy image stacks. Synapsin is expressed in large parts of the bilobed anterior cerebral ganglion including anterior and dorsal projections. Two pairs of ventral neurites run longitudinally into the larval body of which the inner pair shows only weak, scattered synapsin immunoreactivity. In addition, a lateral synapsin immunoreactive projection emerges posteriorly from each ventral longitudinal axon. Double immunostaining shows co-localization of synapsin and serotonin in the cerebral ganglion, the outer and the inner ventral neurites, and the anterior projections. Synapsin and RFamide-like immunoreactivity co-occur in the cerebral ganglion, the outer ventral neurites, and the dorsal projections. Accordingly, the cerebral ganglion and the outer ventral neurites are the only neural structures that co-express the two neurotransmitters and synapsin. The overall neuroanatomical condition of the cycliophoran chordoid larva resembles much more the situation of adult rather than larval life cycle stages of a number of spiralian taxa