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In 1991, Sabath described “larger avian eggs” from the Upper Cretaceous Barun Goyot and Djadokhta Formations of Mongolia. These were later included in the ootaxon Gobioolithus major. Here we recognize the larger avian eggs of Sabath as a distinct ootaxon, Styloolithus sabathi, oogen. et oosp. nov. These eggs differ from those of Gobioolithus in being larger (70 by 32 mm) and more elongate. Microscopically, the shell bears a third layer (possible external zone) thicker than the mammillary layer and nearly as thick as the second layer (possible squamatic zone); the continuous layer (including layers two and three) to mammillary layer thickness ratio is 3.1:1. Within the clutch, the tightly spaced eggs stand with their long axes steeply inclined. Adult remains are associated with two clutches, suggesting an incubation mode similar to that of troodontid maniraptorans, where adults sat atop largely buried eggs. S. sabathi provides evidence that relative egg size in Mesozoic non-ornithuromorph birds had increased markedly from the non-avian theropod condition in oviraptorids and troodontids, but had not yet reached the modern egg-adult proportions of Neornithes. Sediment-bound upright eggs appear common to Enantiornithes and more basal avians, suggesting that like non-avian theropods, these birds lacked chalazae, the chords of albumen allowing egg rotation in modern birds. Absence of this simple structure may have restricted these basal birds to ground nesting in areas with appropriate substrates and not permitted the type of nesting diversity found in Neornithes. Neornithes are the only Mesozoic clade of Dinosauria to nest completely free of sediment; this may have played a crucial role in their surviving the K-Pg mass extinction event.
The paper contains a review of quill mites of the subfamily Picobiinae (Acari: Prostigmata: Syringophilidae) associated with woodpeckers (Aves: Piciformes: Picidae). Three new species are described: Picobia mentalis Skoracki et Unsoeld sp. nov. from Picus mentalis Temminck, Neopicobia ea Skoracki et Unsoeld sp. nov. from Celeus flavus (St. Mueller) (type host), C. elegans (St. Mueller), C. torquatus (Boddaert), and Neopicobia freya Skoracki et Unsoeld sp. nov. from Dryocopus galeatus (Temminck) (type host) and Piculus rubiginosus (Swainson). Additionally, six new host species for Picobia heeri Haller, 1878 and 12 new host species for Picobia dryobatis (Fritsch, 1956) are reported. A complete list of the picobiines parasitising birds of the family Picidae is presented in the tabular form.
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Fossil avian and reptilian eggs and eggshells, from the Cretaceous of Mongolia and USSR (Kazakhstan, Zaisan basin) as well as samples of dinosaurian and the Eocene avian eggshells from USA, China, France and Argentina were studied. Methodological, terminological and biomineralization aspects of eggshell structure are discussed. Considered are different classifications of eggshell according to the structural levels of eggshell matter organization (texture, general histostructure, superficial morphology). Basic types, morphotypes, types of pore system and types of surface ornamentation are the main structural categories employed in the systematic description of fossil material. About 18 groups of fossil eggshells referred to turtles, geckoes, crocodiles, and to 14 “families” or dinosaur and bird oological remains are described. Their composition, occurence, paleobiology and systematics are shortly presented.
Calamicoptes anatidus sp. nov., a new species of rarely found parasitic mites of the family Laminosioptidae (Acari: Astigmata) is described from quill walls of wing covert feathers of Aythya marila Linnaeus (Anseriformes: Anatidae) captured in Poland. This is the first record of the family Laminosioptidae on birds of the order Anseriformes and the first record of this mite family in the fauna of Poland. Females of the new species are most similar to those of C. arenariae Lombert, Gaud et Lukoschus, 1984 and differ from them by the presence of the pygidial shield, which covers dorsal and ventro-lateral parts of the opisthosoma, and by having setae c2 and d2 short and subequal in length, and setae se and cp not reaching the metapodonotal shield.
The Solnhofen (Sixth) specimen of Archaeopteryx is assigned to Wellnhoferia grandis gen. et sp. n. on the basis of qualitative, size-independent autapomorphies. Wellnhoferia differs from Archaeopteryx in a short tail with the estimated number of 16-17 caudals; a nearly symmetric pattern of pedal rays II-IV with metatarsals II and IV of equal length and digit IV substantially shorter than in Archaeopteryx; and the number of four (instead of five) phalanges of pedal digit IV, which most probably results from a phylogenetic reduction rather than individual variation. A combination of large size and details of the pelvic limb suggests a locomotor specialization different from that of Archaeopteryx.
The mature Paroniella reynoldsae spermatozoon exhibits an apical cone of electron-dense material about 2.2 µm long and 0.65 µm wide at its base and two helicoidal crest-like bodies roughly 100 to 150 nra thick. The latter are of different lengths, spiralled and make an angle of about 45° with the spermatozoon axis. The axoneme is of the 9 + '1' trepaxonematan pattern and does not reach the posterior extremity of the gamete. The nucleus is an electron-dense cord 0.25 µm thick coiled in a spiral around the axoneme. The cytoplasm exhibits a posterior densification and contains few small electron-dense granules in regions I, II and V of the spermatozoon. In regions III and IV, it is divided into irregular compartments by walls of electron-dense material. The cortical microtubules are spiralled at an angle of about 45°. The presence of an electron-lucent apical cone containing numerous small granules of electron-dense material has never, to our knowledge, been reported in a cestode. Likewise, a crest-like body forming a terminal spot of electron-dense material located in the prolongation of the apical cone has never been described before in a cestode. Moreover, in this study, we try to show the existence of tight reciprocal phylogenetic relationships between genera within the Davaineidae and the Anoplocephalidae.
A systematic review of pterolichid feather mites of the Psittophagus generic group (Pterolichidae, Pterolichinae) is presented. New feather mite taxa are described: Psittaculobius quadriglobus gen. nov., sp. nov. from the Long-tailed Parakeet Psittacula longicauda (type host) and the Red-breasted Parakeet P. alexandri (Psittacidae, Psittacinae), Psittophagus calyptorhynchi sp. nov. from the Yellow-tailed Black Cockatoo Calyptorhynchus funereus (Cacatuidae, Calyptorhynchinae). A key to all genera and species of the Psittophagus group and taxonomic comments on formerly described species are provided, and host-parasite associations of these mites with the parrots from the Old World are briefly discussed. It is hypothesised that the Psittophagus group originated on the ancestors of Psittaciformes at the same time as other pterolichine groups specific to parrots, but in the process of coevolution with these hosts it has achieved significant success on Cacatuidae only, while on Psittacidae, the representatives of this group have been retained only on few phylogenetic lineages in the Old World.
Two new species of poorly known feather mite genus Neumannella Trouessart, 1916 (Acari, Astigmata) are described from tataupa tinamou Crypturellus tataupa (Temminck, 1815) (Aves, Tinamiformes): Neumannella astacus sp. nov. and N. tataupai sp. nov. The present state of knowledge about this genus is briefly discussed.
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