André Piuz

Late Cretaceous (Cenomanian-Turonian) ammonites from southern Morocco and south western Algeria

On the basis of nine lithostratigraphical profiles, 23 cephalopods taxa (nautilus and ammonites) are described from the Preafrican Trough and the Kem Kem region. Among them, a new species is proposed: Spathites (Jeanrogericeras) asflaensis nov. sp. This fauna is placed in its biostratigraphical framework and correlated with the standard zonation of the late Cenomanian–early Turonian. Moreover, stratigraphic correlations are proposed for the whole Maghreb from the Tarfaya Basin in the west to central Tunisia in the east. Selected taxa reveal the paleogeographical context of the western Tethys; a complex distribution of emerged areas and epicontinental seas impacted by an important marine trangression that constantly modified the costaline.

Cenomanian rotaliids (Foraminiferida) from Oman and Morocco

The small rotaliids (Foraminiferida) found in Cenomanian rock thin sections of Oman and Morocco are diversified. A continuum of morphotypes is divided within 3 taxa described as subspecies of Rotorbinella mesogeensis Tronchetti 1981 from which they share many morphological characteristics. According to features, including shell shape and size, and spiral thickening of the wall, they are named R. m. microformis ssp. nov., R. m. medioformis ssp. nov. and R. m. mesogeensis ssp. nov., the latter being the typical form of Tronchetti 1981. The subspecies mesogeensis is a biostratigraphical marker of the Cenomanian while microformis is known since the Late Albian up to the Late Cenomanian (possibly Early Turonian). Pararotalia boixae sp. nov. comprises specimens previously attributed to P. tuberculifera Reuss 1862 pro parte. This Cenomanian new species (with Campanian affinis forms) is characterized by morphological features that clearly distinct it from the type of Reuss. We found it in the Cenomanian of Oman, but not in contemporaneous Moroccan sediments.

Microcrystals coating the wing membranes of a living insect (Psocoptera: Psyllipsocidae) from a Brazilian cave

Two specimens of Psyllipsocus yucatan with black wings were found with normal individuals of this species on guano piles produced by the common vampire bat Desmodus rotundus. These specimens have both pairs of wings dorsally and ventrally covered by a black crystalline layer. They did not exhibit any signs of reduced vitality in the field and their morphology is completely normal. This ultrathin (1.5 µm) crystalline layer, naturally deposited on a biological membrane, is documented by photographs, SEM micrographs, energy dispersive spectroscopy (EDS) and X-ray diffractometry (XRD). The crystalline deposit contains iron, carbon and oxygen, but the mineral species could not be identified. Guano probably played a role in its formation; the presence of iron may be a consequence of the excretion of iron by the common vampire bat. This enigmatic phenomenon lacks obvious biological significance but may inspire bionic applications. Nothing similar has ever been observed in terrestrial arthropods.