First zoeal stage of ? Cataleptodius parvulus (Fabricius, 1793) and Xanthodius denticulatus (White, 1848) (Decapoda: Brachyura): larval evidences and systematic position

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Description of two new species of Hisonotus Eigenmann & Eigenmann, 1889 (Ostariophysi, Loricariidae) from the rio Parana-Paraguay basin, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comparative analysis of the cranial osteology and evolutionary traits of micrastur gilvicollis, micrastur ruficollis and micrastur semitorquatus (aves: falconiformes)

The cranial osteology of Micrastur gilvicollis (Vieillot, 1817), Micrastur ruficollis (Vieillot, 1817) and Micrastur semitorquatus (Vieillot, 1817) is comparatively and meticulously described to characterize each of the species and to determine which traits the species have in common and which are distinct. These traits will be used a posteriori for phylogenetic analysis. Our results indicate that M. gilvicollis and M. ruficollis are closely related, as they share a large number of traits, including a lacrimal bone with a distal portion that is approximately half as long as the proximal portion and a parasphenoid rostrum that covers 50% of the distance between the occipital condyle and pterygoid. Similarly, M. gilvicollis and M. semitorquatus both have a partially fused craniofacial flexion zone. In both M. ruficollis and M. semitorquatus, the symphyseal region of the mandible is 1/5 the total length of the mandible. The diagnostic traits for each of these species are as follows: a) in M. gilvicollis, the interorbital distance is 1/3 the length of the parietal, and the zygomatic process stretches 1/5 of the distance from the orbital arch to the jugal arch; b) in M. ruficollis, the interorbital distance is 2/5 of the length of the parietal and the zygomatic process extends 1/4 of the distance from the orbital arch to the jugal arch; and c) in M. semitorquatus, the interorbital distance is 3/7 the length of the parietal and the distal portion of the lacrimal is 1/3 the length of the proximal portion. Among the three species, M. gilvicolis and M. ruficollis share the most traits, which leads us to infer that these species are more closely related to one another than they are to M. semitorquatus. Phylogenetic analysis performed a posteriori may confirm the relationship between these three species.

Caridean Shrimps Associated with the Slimy Sea Plume (Pseudopterogorigia americana) in Midsummer at Guana Island, British Virgin Islands, West Indies

Fifty-one slimy sea plumes (Pseudopterogorgia americana Gmelin, 1791) were sampled for caridean shrimps at Guana Island, British Virgin Islands, during one week in July 1992. Sam- pling depth ranged from 3-22 m. Nine species were collected: Hippolyte nicholsoni Chace, 1972; Latreutes sp.; Neopontonides chacei Heard, 1986; Perclimenes cf. patae Heard and Spotte, 1991; Periclimenes cf. pauper Holthuis, 1951; Periclimenes sp.; Pseudocoutierea antillensis Chace, 1972; Tozeuma cf. cornutum Milne Edwards, 1881; and Trachycaris rugosa (Bate, 1888). A total of 1,418 specimens (including fragments) was obtained. The number of shrimp species per gorgonian ranged from 1-5; one gorgonian harbored 156 shrimps. The two predominant species, N. chacei and H. nicholsoni, occupy different mean depths (12.6 and 8.2 m, respectively). Sexual dimorphism assessed with Mann-Whitney U-tests was not apparent in the specimens of N. chacei (P > 0.05), but females of H. nicholsoni were significantly larger than males (P < 0.001). Minimum carapace length (CL, the tip of the rostrum to the posterior dorsal margin of the carapace) at which male N. chacei acquire a single appendix masculina spine is 1.25 mm; male H. nicholsoni can acquire a single spine at 0.9 mm CL. Histological sections of male N. chacei showed that shrimp with 0 or 1 spine are least likely to be mature. Female N. chacei can become ovigerous at 1.9 mm CL and female H. nicholsoni at 1.2 mm CL. The taxonomic status of 5 of the 9 species collected is uncertain.

Geographic Variation in Sea Otters, Enhydra lutris

Univariate and multivariate analyses of 20 skull characters of 304 adult sea otters from throughout the geographic range strongly suggest that three subspecies should be recognized. The nominate form, Enhydra lutris lutris, occurs from the Kuril Islands north to the Commander Islands in the western Pacific Ocean. Individuals of E. l. lutris are characterized by large size and wide skulls with short nasal bones. E. 1. nereis is found along the California coast and off San Nicolas Island, where the species recently has been reintroduced from coastal California. Specimens of E. 1. nereis have narrow skulls with a long rostrum and small teeth, and usually lack the characteristic notch in the postorbital region found in most specimens of the other two subspecies. A new subspecies described by Don E. Wilson in this report, occurs throughout the Aleutian Islands and southward in the eastern Pacific to Washington. Specimens of the new subspecies are intermediate in size in most, but not all, characters and have longer mandibles than either of the other two subspecies

Taxonomy of the Common Dolphins of the Eastern Pacific Ocean

Delphinus bairdii Dall is a species of dolphin distinct from D. delphis Linnaeus, with which it has usually been synonymized. D. bairdii has a longer rostrum relative to the zygomatic width of the skull; the ratio of these measurements falls at 1.55 or above for bairdii and 1.53 and below for delphis. In the eastern Pacific Ocean, D. bairdii is found in the Gulf of California and along the west coast of Baja California, Mexico; D. delphis is presently found in the waters off California. Until approximately the beginning of the present century, bairdii occurred farther north in the eastern Pacific Ocean, at least to the Monterey Bay area of California. Restriction of bairdii to more southerly waters, probably as an indirect result of a change in water temperature, may have permitted delphis to move into inshore Californian waters. The Pacific population of D. delphis has a somewhat shorter rostrum than the Atlantic population, and is perhaps subspecifically different. A thorough analysis of the entire genus Delphinus is needed before the relationship of all the populations can be understood and names properly applied.

Morphological description of the mouthparts of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Psyllidae)

Scanning (SEM) and transmission (TEM) electron microscopy were used to elucidate the morphology of the rostrum, as well as the mandibular and maxillary stylets of the psyllid Diaphorina cirri, vector of phloem-inhabiting bacteria associated with citrus huanglongbing (HLB) disease. D. cirri has a cone-shaped rostrum that extends behind the pair of prothoracic coxae. The stylet bundle comprises a pair of mandibular (Md) and maxillary (Mx) stylets with a mean length of 513.3 mu m; when retracted, their proximal portions form a loop and are stored in the crumena (Cr). Serial cross-sections of the rostrum revealed that the mandibles are always projected in front of the maxillary stylets. The two maxillary stylets form the food and salivary canals, with diameters of 0.9 mu m and 0.4 mu m respectively. These two canals merge at the end of the stylets forming a common duct with a length of 4.3 mu m and a mean diameter of 0.9 mu m. The acrostyle, a distinct anatomical structure present in the common duct of aphid maxillary stylets, was not observed by TEM in the ultrathin cross-sections of the common duct (CD) of D. citri. This study provides new information on D. citri mouthparts that may help to understand the behaviour of this important vector of HLB-associated bacteria. (C) 2011 Elsevier Ltd. All rights reserved.

A remarkable new species of flesh-fly mimicking weevil (Coleoptera: Curculionidae: Conoderinae) from Southeastern Brazil

Timorus sarcophagoides, new species (type-locality: Brazil, Minas Gerais, Santana do Riacho - Serra do Cipo, 43 degrees 35'W 19 degrees 17'S, 1200-1300m ASL), is described and illustrated. The new species can be distinguished mainly from the other species of the genus by the sexual dimorphism of the male rostrum armed with a hooked tubercle at the base of the dorsal carina, while the tubercle is absent in the female and the corresponding region of the carina is only tumid. The new species has a striking pattern of coloration and behavior that mimics flesh-flies in the family Sarcophagidae. Observations on the natural history of the new species are reported and discussed.

Morphological and genetic variability in Hippolyte obliquimanus dana, 1852 (Decapoda, Caridea, Hippolytidae) from Brazil and the caribbean sea

Hippolyte obliquimanus is a marine shrimp reported from the Caribbean Sea and Brazil. The literature provides indications for morphological variation between populations from those regions and the species has a troubled taxonomic history. The aims of this study were to analyse morphological and genetic variation in the populations of H. obliquimanus from Brazil and the Caribbean Sea and to verify if those might support separation of H. obliquimanus into two or more species. This hypothesis was tested with the analysis of morphological and genetic data (mitochondrial gene 16S and the barcode region Cytochrome Oxidase I). The material analysed was obtained from samples and from loans of zoological collections. The rostrum as well as pereiopods 3, 4, and 5 were the adult morphological characters that showed variation, but this occurred in samples from both regions, Brazil and the Caribbean Sea. The sequences of the 16S gene were identical among all specimens analysed. There was, however, variation among the sequences of the barcoding gene COI (<2.0%); this divergence separated the specimens into two groups (Brazil versus the Caribbean) and these groups did not share haplotypes. In conclusion, specimens from the regions analysed showed both morphological and genetic variation, but these did not support the separation of H. obliquimanus into two or more species.

Jaw mechanics of the pterosaur skull construction and the evolution of toothlessness

In the present study, pterosaur skull constructions were analysed using a combined approach of finite element analysis (FEA), static investigations as well as applying classical beam theory and lever mechanics. The study concentrates on the operating regime „bite“, where loads are distributed via the dentition or a keratinous rhamphotheca into the skull during jaw occlusion. As a first step, pterosaur tooth constructions were analysed. The different morphologies of the tooth construction determine specific operational ranges, in which the teeth perform best (= greatest resistance against failure). The incomplete enamel-covering of the pterosaur tooth constructions thereby leads to a reduction of strain and stress and to a greater lateral elasticity than for a complete enamel cover. This permits the development of high and lateral compressed tooth constructions. Further stress-absorption occurs in the periodontal membrane, although its mechanical properties can not be clarified unambiguously. A three-dimensionally preserved skull of Anhanguera was chosen as a case-study for the investigation of the skull constructions. CT-scans were made to get information about the internal architecture, supplemented by thin-sections of a rostrum of a second Anhanguera specimen. These showed that the rostrum can be approximated as a double-walled triangular tube with a large central vacuity and an average wall-thickness of the bony layers of about 1 mm. On base of the CT-scans, a stereolithography of the skull of Anhanguera was made on which the jaw adductor and abductor muscles were modelled, permitting to determine muscular forces. The values were used for the lever mechanics, cantilever and space frame analysis. These studies and the FEA show, that the jaw reaction forces are critical for the stability of the skull construction. The large jugal area ventral to the orbita and the inclined occipital region act as buttresses against these loads. In contrast to the orbitotemporal region which is subject to varying loading conditions, the pattern in the rostrum is less complex. Here, mainly bending in dorsal direction and torsion occur. The hollow rostrum leads to a reduction of weight of the skull and to a high bending and torsional resistance. Similar to the Anhanguera skull construction, the skulls of those pterosaur taxa were analysed, from which enough skull material is know to permit a reliable reconstruction. Furthermore, FEA were made from five selected taxa. The comparison of the biomechanical behaviour of the different skull constructions results in major transformational processes: elongation of rostra, inclination of the occipital region, variation of tooth morphology, reduction of the dentition and replacement of teeth by a keratinous hook or rhamphotheca, fusion of naris and antorbital fenestra, and the development of bony and soft-tissue crests. These processes are discussed for their biomechanical effects during bite. Certain optional operational ranges for feeding are assigned to the different skull constructions and previous hypotheses (e.g. skimming) are verified. Using the principle of economisation, these processes help to establish irreversible transformations and to define possible evolutionary pathways. The resulting constructional levels and the structural variations within these levels are interpreted in light of a greater feeding efficiency and reduction of bony mass combined with an increased stability against the various loads. The biomechanical conclusive pathways are used for comparison and verification of recent hypothesis of the phylogenetic systematics of pterosaurs.

Phylogenomische Analysen bei Metazoen - Zur Stellung der Xenoturbellida und Syndermata

Im Rahmen der vorliegenden Dissertation wurde die phylogenetischen Stellungen der Xenoturbellida (Deuterostomia) und der Syndermata (Protostomia) mit phylogenomischen Techniken untersucht. Auf methodischer Ebene konnte gezeigt werden, dass ribosomale Proteine aufgrund ihres mittleren bis hohen Konservierungsgrades, ihrer Häufigkeit in kleineren EST-Projekten, damit verbunden ihrer Häufigkeit in Datenbanken und ihres phylogenetischen Informationsgehalts nützliche Werkzeuge für phylogenetische Fragestellungen sind. Es konnte durch phylogenetische Rekonstruktionen und Hypothesentests auf Basis eines 11.912 Aminosäuren langen Datensatzes gezeigt werden, dass die Xenoturbellida innerhalb der Deuterostomia eine Schwestergruppenbeziehung zu den Ambulacraria eingehen. Diese Arbeit zeigt im Vergleich aller bisher durchgeführten Arbeiten die beste statistische Unterstützung für diese Topologie. Weiterhin konnte untermauert werden, dass die Urochordata vermutlich anstelle der Cephalochordata die Schwestergruppe der Vertebrata sind. Der Vergleich der publizierten Xenoturbella EST-Datensätze mit dem eigenen Datensatz ließ den Rückschluß zu, dass ESTs offenbar klar weniger anfällig gegen Kontaminationen mit Erbmaterial (DNA+RNA) anderer Spezies sind als PCR-Amplifikate genomischer oder mitochondrialer Gene. Allerdings bestimmt anscheinend der physiologische Zustand der Tiere die Repräsentation von Transkriptklassen wie Stressproteine und mitochondriale Transkripte. Die bakteriellen Transkripte in einem der EST-Datensätze stammen vermutlich von Chlamydien, die möglicherweise symbiontisch in Xenoturbella bocki leben. Im Bereich der Protostomia wurden drei EST-Projekte für Vertreter der Syndermata durchgeführt. Basierend auf drei verschiedenen Proteinalignment-Datensätzen von ca. 11.000 Aminosäuren Länge konnte gezeigt werden, dass die Syndermata innerhalb der Spiralia einzugruppieren sind und dass sie mit den Gnathostomulida das monophyletische Supertaxon Gnathifera bilden. Die genaue phylogenetische Position der Syndermata innerhalb der Spiralia konnte hingegen noch nicht eindeutig geklärt werden, ebenso wie kein kongruenter Beweis für die Existenz des Supertaxons Platyzoa gefunden werden konnte. Im Rahmen der Untersuchung der internen Phylogenie der Syndermata konnten drei der fünf konkurrierenden Hypothesen aufgrund der Paraphylie der Eurotatoria ausgeschlossen werden. Da keine Daten der Seisonidea in den Analysen implementiert waren, bleibt die Frage der internen Phylogenie der Syndermata letztlich offen. Klar ist jedoch, dass die Eurotatoria nicht wie bislang angenommen monophyletisch sind, da die räderorgantragenden Bdelloidea keinesfalls den morphologisch diesbezüglich ähnlichen Monogononta ähnlich sind, sondern den räderorganlosen Acanthocephala näher stehen. Die Abbildung der molekularen Phylogenie auf die morphologischen Verhältnisse zeigt, dass das Räderorgan (partiell oder komplett) offenbar kurz nach der Aufspaltung der Syndermata in Monogononta und Acanthocephala + Bdelloidea in der Acanthocephala + Bdelloidea-Linie reduziert wurde. Die Entstehung des einziehbaren hinteren Körperteils (Rostrum bei Bdelloidea bzw. Proboscis bei Acanthocephala) in der Acanthocephala + Bdelloidea-Linie könnte das Schlüsselereignis zur Entstehung des Endoparasitismus der Acanthocephala gewesen sein.

European lobsters (Homarus gammarus) captured around the rocky island of Helgoland (German Bight, North Sea) from 2005 to 2015 - A mark-recapture program -

European lobsters were captured by employees of the Marine Biological Station and local fishermen from the rocky subtidal zone around the island of Helgoland (North Sea, 54°11.3'N, 7°54.0'E) and from the Helgoland Deep Trench, located south west of the island. The animals were captured by pots, traps, trawl and divers. All measured lobsters were tagged and released. A tagged lobster was classified by the absence or presence of colour tag and/or T-bar tag. Data of lobsters contains capture date, fresh weight, carapace lengths, sex and the information if lobsters were egg-bearing and tagged. Furthermore, data of commercial landed lobsters are included.

The internal cranial anatomy of the Plesiosauria (Reptilia, Sauropterygia): evidence for a functional secondary palate

In the late 19th Century, the choanae (or internal nares) of the Plesiosauria were identified as a pair of palatal openings located rostral to the external nares, implying a rostrally directed respiratory duct and air path inside the rostrum. Despite obvious functional shortcomings, this idea was firmly established in the scientific literature by the first decade of the 20th Century. The functional consequences of this morphology were only re-examined by the end of the 20th Century, leading to the conclusion that the choanae were not involved in respiration but instead in underwater olfaction, the animals supposedly breathing with the mouth agape. Re-evaluation of the palatal and internal cranial anatomy of the Plesiosauria reveals that the traditional identification of the choanae as a pair of fenestrae situated rostral to the external nares appears erroneous. These openings more likely represent the bony apertures of ducts that lead to internal salt glands situated inside the maxillary rostrum. The 'real' functional choanae (or caudal interpterygoid vacuities), are situated at the caudal end of the bony palate between the sub-temporal fossae, as was suggested in the mid-19th Century. The existence of a functional secondary palate in the Plesiosauria is therefore strongly supported, and the anatomical, physiological, and evolutionary implications of such a structure are discussed.

An unusual pliosaur (Reptilia, Sauropterygia) from the Kimmeridgian (Upper Jurassic) of northeastern Mexico

We here describe the rostrum of a pliosaur from the Kimmeridgian of northeastern Mexico. The specimen comes from the Upper Jurassic La Casita Formation (Kimmeridgian - Tithonian) and represents one of the few Plesiosauria in the area. The internal anatomy of the specimen is partly visible through cross-sections, which reveal a hitherto undescribed rostral prolongation of a paired bone of the interorbital area, probably the parietal or frontal beneath the premaxillae. The specimen also provides new information on the morphology and function of the choanae. In light of these morphological data, the new pliosaur shows similarities both with the European Late Jurassic genus Pliosaurus and the Australian Early Cretaceous Kronosaurus.

On the microstructure, growth pattern and original porosity of belemnite rostra: insights from calcitic Jurassic belemnites

Calcitic belemnite rostra are usually employed to perform paleoenvironmental studies based on geochemical data. However, several questions, such as their original porosity and microstructure, remain open, despite they are essential to make accurate interpretations based on geochemical analyses.This paper revisits and enlightens some of these questions. Petrographic data demonstrate that calcite crystals of the rostrum solidum of belemnites grow from spherulites that successively develop along the apical line, resulting in a “regular spherulithic prismatic” microstructure. Radially arranged calcite crystals emerge and diverge from the spherulites: towards the apex, crystals grow until a new spherulite is formed; towards the external walls of the rostrum, the crystals become progressively bigger and prismatic. Adjacent crystals slightly vary in their c-axis orientation, resulting in undulose extinction. Concentric growth layering develops at different scales and is superimposed and traversed by a radial pattern, which results in the micro-fibrous texture that is observed in the calcite crystals in the rostra.Petrographic data demonstrate that single calcite crystals in the rostra have a composite nature, which strongly suggests that the belemnite rostra were originally porous. Single crystals consistently comprise two distinct zones or sectors in optical continuity: 1) the inner zone is fluorescent, has relatively low optical relief under transmitted light (TL) microscopy, a dark-grey color under backscatter electron microscopy (BSEM), a commonly triangular shape, a “patchy” appearance and relatively high Mg and Na contents; 2) the outer sector is non-fluorescent, has relatively high optical relief under TL, a light-grey color under BSEM and low Mg and Na contents. The inner and fluorescent sectors are interpreted to have formed first as a product of biologically controlled mineralization during belemnite skeletal growth and the non-fluorescent outer sectors as overgrowths of the former, filling the intra- and inter-crystalline porosity. This question has important implications for making paleoenvironmental and/or paleoclimatic interpretations based on geochemical analyses of belemnite rostra.Finally, the petrographic features of composite calcite crystals in the rostra also suggest the non-classical crystallization of belemnite rostra, as previously suggested by other authors.