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Characters of the larval head of Mycetina cruciata [Schaller] [Coleoptera: Endomychidae] and their phylogenetic implications

100%

Beutel R. G., Weide D., Bernhard D.

Annales Zoologici

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2000

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tom 50

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nr 1

Head structures, especially internal features of the larva of Mycetina crucicita are described and discussed with respect to their functional and phylogenetic relevance. Spore masses are collected in the preoral chamber, mechanically treated by the mandibular molae, diluted with secretions, and sucked back by the unusually strong prepharyngcal and pharyngeal pumping apparatus. The presence of tube-like glands is a possible synapomorphy of all cucujiform superfamilies. Posterior tentorial arms which are shifted anteriorly and separated from the tentorial bridge, thin and flattened dorsal tentorial arms, and reduced anterior arms are apomorphic features shared by larvae of Mycetina, Coccinella, Glischrochilus, and cleroid larvae. The origin of a strong bundle of M. tentoriostipitalis from the dorsal hypopharyngeal wall is another unusual derived character state shared by larvae of these taxa. Whether these structural affinities are due to a closer relationship between Endomychidac, Coccinellidae, Nitidulidae, and Cleroidea, or due to parallelism is a matter of further investigation. Presumably derived external features of the head are shared by several genera of Endomychidae. They suggest a closer relationship between Mycetina, Aphorista, Amphix, Epipocinae (excluding Periptyctus), and Bystus (Anamorphinae). Larval characters are in conflict with the monophyly of Lycoperdininae and Epipocinae.

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Fused and vaulted nasals of tyrannosaurid dinosaurs: Implications for cranial strength and feeding mechanics

67%

Snively E., Henderson D. M., Phillips D. S.

Acta Palaeontologica Polonica

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2006

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tom 51

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nr 3

Tyrannosaurid theropods display several unusual adaptations of the skulls and teeth. Their nasals are fused and vaulted, suggesting that these elements braced the cranium against high feeding forces. Exceptionally high strengths of maxillary teeth in Tyrannosaurus rex indicate that it could exert relatively greater feeding forces than other tyrannosaurids. Areas and second moments of area of the nasals, calculated from CT cross−sections, show higher nasal strengths for large tyrannosaurids than for Allosaurus fragilis. Cross−sectional geometry of theropod crania reveals high second moments of area in tyrannosaurids, with resulting high strengths in bending and torsion, when compared with the crania of similarly sized theropods. In tyrannosaurids trends of strength increase are positively allomeric and have similar allometric exponents, indicating correlated progression towards unusually high strengths of the feeding apparatus. Fused, arched nasals and broad crania of tyrannosaurids are consistent with deep bites that impacted bone and powerful lateral movements of the head for dismembering prey.

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Vesiculation of food vacuoles and segregation of ingesta: peculiarities of the digestive cycle in the raptorial ciliate Homalozoon vermiculare

67%

Baumberg D., Hausmann K.

Acta Protozoologica

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2007

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tom 46

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nr 1

Ograniczanie wyników

1 Acta Palaeontologica Polonica

1 Acta Protozoologica

1 Annales Zoologici

1 Baumberg D.

1 Bernhard D.

1 Beutel R. G.

1 Hausmann K.

1 Henderson D. M.

1 Phillips D. S.

1 Snively E.

1 Weide D.

1 2007

1 2006

1 2000

Characters of the larval head of Mycetina cruciata [Schaller] [Coleoptera: Endomychidae] and their phylogenetic implications

Fused and vaulted nasals of tyrannosaurid dinosaurs: Implications for cranial strength and feeding mechanics

Vesiculation of food vacuoles and segregation of ingesta: peculiarities of the digestive cycle in the raptorial ciliate Homalozoon vermiculare