Early-Middle Ordovician cephalopods from Ny Friesland, Spitsbergen – a pelagic fauna with Laurentian affinities

The collection of cephalopods from eight sampling horizons within the Olenidsletta Member, Valhallfonna Formation, Floian–Dapingian, from Profilstranda and nearby Profilbekken, Ny Friesland, Spitsbergen, resulted in the detection of 31 species, 20 genera, and 12 families from the Ellesmerocerida, Endocerida, Riocerida, Dissidocerida, Orthocerida, Tarphycerida, and Oncocerida. Of these, five genera (Ethanoceras gen. nov., Hinlopoceras gen. nov., Nyfrieslandoceras gen. nov., Olenidslettoceras gen. nov., Svalbardoceras gen. nov.) and 19 species (Bactroceras fluvii sp. nov., Buttsoceras buldrebreenense sp. nov., Cycloplectoceras hinlopense sp. nov., Cyclostomiceras profilstrandense sp. nov., Deltoceras beluga sp. nov., Eosomichelinoceras borealis sp. nov., Ethanoceras solitudines gen. et sp. nov., Hemichoanella occulta sp. nov., Hinlopoceras tempestatis gen. et sp. nov., H. venti gen. et sp. nov., Lawrenceoceras ebenus sp. nov., L. larus sp. nov., Litoceras profilbekkenense sp. nov., Nyfrieslandoceras bassleroceroides gen. et sp. nov., Olenidslettoceras farmi gen. et sp. nov., Protocycloceras minor sp. nov., Proterocameroceras valhallfonnense sp. nov., Svalbardoceras sterna gen. et sp. nov., S. skua gen. et sp. nov.) are new. The diagnoses of the Cyptendoceratidae, Bactroceratidae and of Deltoceras Hyatt, 1894 are emended. Well preserved early growth stages in several species are remarkable. Turnover between the sampling horizons and between sampling intervals is high. The differences in composition, diversity and evenness of the assemblages are interpreted as reflecting changing depth and oxygenation depositional bottom conditions. The co-occurrence of endemic and cosmopolitan species is interpreted as resulting from a high vertical niche differentiation and from eustatically generated lateral shifts of facies zones. Based on calculations of phragmocone implosion depths, depositional depths of 50–130 m are plausible for the Olenidsletta Member, supporting independent evidence from biomarker signatures. Several cephalopod species of the Olenidsletta Member represent odd mosaics of morphological features of previously known cephalopods which cannot be unambiguously assigned to one of the existing cephalopod higher taxa. Results from a cladistic analysis shed new light on the early evolution of the Oncocerida and Orthocerida.

The role of taphonomy in cladistic analysis: A case study in Permian bivalves.

The Megadesmidae (Bivalvia, Anomalodesmata) fossil record was examined in order to assess the role of taphonomy in cladistic analysis. Megadesmids are thick-shelled, infaunal, suspension-feeding bivalves. Our data indicate that their fossil record seems biased in favor of thick-shelled, shallow-burrowing genera and/or deep­burrowing forms. Consequently, there is a relation between the mode of life (shallow versus deep) and the resolution and quality of the fossil record. Deep-burrowers (Vacunella) are often preserved in life position offering a more accurate (temporal and spatial) fossil record, adequate for paleoecological inferences, while shallow-burrower shells (Plesiocyprinella), that are more prone to post-mortem transport and temporal mixing, offer a record with poor spatial and temporal resolution. The identification of homoplasy among infauna! bivalves constitutes a major challenge for their cladistic analysis. Within Megadesmidae intrinsic (bauplan limitations) and extrinsic (better preservational potential) factors favor the occurrence and preservation of homoplasy among the deep-burrowers. The implications are: a) clustering of deep-burrowing bivalves (Vacunella, Roxoa) due to parallel homoplasies, forming "adaptive", not necessarily "evolutive" taxa, and b) lower consistency indices in their cladistic analysis.

Calcatedessa gen.n. a new genus sister to Grammedessa Correia & Fernandes (Heteroptera, Pentatomidae, Edessinae) based on a cladistic analysis

Grammedessa Correia & Fernandes, 2016 is a genus raised to include some species of Edessa Fabricius, 1803 that is a very common group of stink bugs inhabiting only the Neotropical region. Grammedessa was proposed excluding a few species that were morphologically similar but not completely fitting in the diagnostic requirements of the genus. Grammedessa was also proposed without considering a phylogenetic context. In this work, the monophyly of Grammedessa was tested using a cladistic analysis, including all species that were originally excluded, under both Maximum Parsimony and Bayesian methods. As a result, six new species are now included in Grammedessa, which will be described in a forthcoming paper; Edessa botocudo Kirkaldy, 1909 was considered an unnecessary new name for Edessa hamata Walker, 1868 that was transferred to Grammedessa, resulting in G. hamata (Walker, 1868) comb.n. Calcatedessa gen.n., a new genus sister to Grammedessa, is here proposed to include four new species: C. anthomorpha sp.n., C. clarimarginata sp.n., C. germana sp.n. and C. temnomarginata sp.n. The Calcatedessa–Grammedessa clade and both genera were recovered as monophyletic by Maximum Parsimony and Bayesian methods. An identification key to the species of Calcatedessa gen.n. is provided. The new genus is distributed in Guyana, Suriname, French Guyana, and Brazil.

Revised classification of the New World Cylapini (Heteroptera: Miridae: Cylapinae): taxonomic review of the genera Cylapinus, Cylapoides and Peltidocylapus and a morphology-based phylogenetic analysis of tribe Cylapini

Cylapini, as currently circumscribed, is a relatively small group of plant bugs currently comprising 17 genera and 65 species. Most representatives of the tribe are distributed in the New World (10 genera and 47 species) with other members occurring in the Afrotropical, Oriental, and Australian regions. They have primarily tropical and subtropical distributions with only a few members inhabiting temperate regions. This paper provides a taxonomic review of three of the New World Cylapini genera: Cylapinus Carvalho, 1986, Cylapoides Carvalho, 1952, and Peltidocylapus Poppius, 1909. Most species are diagnosed and redescribed. Eight new species are described as new: Cylapinus yasunagai sp. nov., Peltidocylapus calyciformis sp. nov., P. caudatus sp. nov., P. ecuadorensis sp. nov., P. pallidus sp. nov., P. parallelus sp. nov., P. simplex sp. nov., and P. spinosus sp. nov. Cylapus festinabundus Bergroth, 1922 is transferred to Peltidocylapus (comb. nov.). Illustrations of male genitalia, scanning electron micrographs of selected structures of certain species, and an identification key of the genera Cylapinus, Cylapoides and Peltidocylapus are provided. Female genitalia are described and illustrated for the first time for most genera of Cylapini. A cladistic analysis of the tribe based on 81 morphological characters is presented as a contribution to the understanding of the ingroup relationships of Cylapini and its relationships with other groups of Cylapinae. The analysis comprises 30 ingroup species and 15 outgroup species. Both equal- and implied weighting parsimony analyses were used in the phylogenetic reconstruction. This analysis was based solely on morphological characters because an insufficient number of specimens suitable for molecular studies were available for most taxa. The study confirmed a close affinity of the taxa currently included in Cylapini, but the tribe was rendered paraphyletic by inclusion of the tribe Vanniini. The grouping comprising both Cylapini + Vanniini and most of its subordinated clades received low nodal support. Both analyses recovered a decisively supported clade comprising the New World genera Amapacylapus, Cylapus, Peltidocylapus, and Valdasus which accommodate most of the Cylapini species, justifying the recognition of the Cylapus complex suggested by previous authors. The results presented here are discussed and compared with previous phylogenetic hypotheses based on different datasets.

Character correlation and its use for identification

A method is presented for correlating phylogenetic characters through cladistic analysis. It extends the use of phylogenetic datasets for diagnostic purposes. It improves matrix-based identification tools by predicting novel character-state combinations that were not observed when the key was constructed. By interpreting homoplasy as analytical error, hypothetical character-state combinations are tested for the homoplasy that they would add to the shortest tree(s). The correlation is equal to the homoplasy summed across all state combinations, divided by a maximum possible value. The results depend on uncertainty about the sequence of state transitions and their overlap among characters. A correlation index r is proposed for sets of non-additive characters; it is a kind of multiple-regression value, and its ensemble value R is a statistic of a whole matrix. This approach can be used to select sets of the best "proxy" characters to substitute for unobservable characters of interest. The concept can be extended to continuous characters. Worked examples are given with datasets of various insect orders.

Heteropelta boboi n. gen., n. sp. an armored archosauriform (Reptilia: Archosauromorpha) from the Middle Triassic of Italy

Heteropelta boboi is a new archosauriform reptile from the upper Anisian of northeastern Italy represented by a fragment of dorsal armor with a row of neural arches of the dorsal vertebrae. The dorsal armor of the new taxon is composed of two columns of paramedian osteoderms and at least six columns of lateral osteoderms. Unlike other armored archosaurs, the osteoderms are imbricated with the posterior osteoderm overlapping the anterior one. The low neural arches bear small neural spines and long postzygapophyses. The osteoderms of the lateral columns increase in size and change in shape from the most medial to the most lateral columns. Among the Archosauriformes, only the non-archosaur proterochampsians Vancleavea campi, Litorosuchus somnii, and the doswelliids have dorsal armor comprised of more than two columns of osteoderms per side, but the morphology and arrangement of their osteoderms is unlike those of the new Italian taxon. A cladistic analysis of Archosauromorpha positions Heteropelta boboi as either a basal phytosaur or a basal suchian. However, a second cladistic analysis focused on armored archosaurs alternatively positions the new taxon as a basal archosauriform, basal suchian, basal loricatan or crocodylomorph. Better resolution of the phylogenetic relationships of Heteropelta boboi will likely be obtained only with the discovery of cranial and postcranial remains associated with its diagnostic armor elements.

Belemnite phylogeny and decline during the mid-Cretaceous

Belemnites are common fossil coleoid cephalopods of the Mesozoic. They began to diversify in the Triassic-Early Jurassic and maintained this diversity until the early Early Cretaceous. During the mid-Cretaceous, they declined in diversity and distribution, being restricted to only the Boreal and Austral Realm since the Turonian. Here, I present the first cladistic analysis of belemnite phylogeny, spanning taxa representative of the whole diversity and stratigraphic range of the group. This analysis shows that the usually applied subdivision of all belemnites into "Belemnitina" and "Belemnopseina" is not supported. A newly identified clade, the Pseudoalveolata, is suggested here. Pseudoalveolate belemnites represent the last remaining belemnites after the Aptian. Oceanic anoxia and warming are likely the main cause of the mid- Cretaceous belemnite decline, resulting in the Aptian-Albian dominance of the warm-adapted pseudoalveolate genus Neohibolites. The rise of teleost fish diversity during the mid- Cretaceous is discussed and its relevance for belemnite evolution. Some teleosts (e.g., Enchodus) might have taken over the mesopredator niches left by belemnites during the mid- Cretaceous, being better adapted to warming seas. Belemnites were not able to recover their earlier widespread distribution and diversity and the last remaining, disjunctly distributed families, the northern Belemnitellidae and southern Dimitobelidae, became extinct at the K/Pg-boundary.

Description of a New Scaled Species of Ptychostomella (Gastrotricha: Macrodasyida) from the Brazilian Coast and a Cladistics Analysis of the Genus

A new species of marine Gastrotricha from the north coast of São Paulo state, Brazil, is described. Adults of Ptychostomella sebastiana sp. nov. are unique in that they possess a pair of dorsolateral “rod-like” cephalic sensory organs and subrectangular scales covering the lateral body surfaces. A cladistic analysis was performed to investigate the internal relationship of the representatives of the taxa based on morphological data. Our analysis supported the monophyly of the taxon Ptychostomella, but its internal phylogenetic relationships are not well established due to the low phylogenetic signal of morphological characters used in the present study.

Harvestmen in the semiarid: a new genus and three new species of Pachylinae (Opiliones: Gonyleptidae) from Caatinga dry vegetation, with a cladistic analysis

Opiliones are highly diverse in the Neotropics. Because of biological constraints, most harvestmen communities are associated with humid forests, exhibiting a high species diversity and endemism in these habitats. Drier formations, such as the Caatinga biome in northeastern Brazil, are less diverse and still considered under-sampled for the order. This study represents an effort to examine the aforementioned diversity by describing a new Gonyleptidae genus, Sertanejagen. nov., comprising two new species from Ceará state, Sertaneja bicuspidatasp. nov. and Sertaneja crassitibialissp. nov., and one new species from Rio Grande do Norte state, Sertaneja falcatasp. nov. A morphological cladistic analysis consisting of 20 terminals and 72 characters was performed to evaluate monophyly of the new genus and relate it to other Gonyleptidae. The analysis resulted in a single most parsimonious tree, corroborating Sertanejagen. nov. monophyly and relatedness to Gyndoides springmanni Soares & Soares, 1947, which in turn is the sister group to the DRMN clade. Taking into account the morphological traits and phylogenetic placement of Sertanejagen. nov., we chose to place the new genus in Pachylinae despite its polyphyletic status, given that the Sertanejagen. nov. clade is closely related to one of the Brazilian Pachylinae lineage. A resolution to the Pachylinae conundrum is needed to further explain the subfamily intricacies. Future research requires a larger scope, but currently, based on the new genus monophyly, support, and relatedness, we formally propose its creation and hope to shed light on the possible evolutionary scenarios for the subfamily.