ALBERT

Description: The south-western Indian Ocean islands, excluding the microcontinent of Madagascar, are geologically complex and diverse. They have been subject to drastic sea level changes, volcanic events and anthropogenic changes, all of which have contributed to confuse understanding of their avian biogeography. An array of factors have affected these avifaunas, based on palaeontological, historical and molecular evidence,which together have shown that avian biogeography is not congruent with the relative age and size of the islands.

Description: A synthesis of the stratigraphy of the Maastrichtian Stage in its extended type area, that is, southern Limburg (the Netherlands), and adjacent Belgian and German territories, is presented with a brief historical overview. Quarrying activities at the large quarry complex of ENCI-HeidelbergCement Group will officially come to an end on July 1, 2018. However, the stratotype section below the Lichtenberg farmstead and directly behind the main office building at the Lage Kanaaldijk (Maastricht), will be preserved, as will various faces within the quarry complex. Strata of Maastrichtian age include the Vijlen, Lixhe 1-3 and Lanaye members of the Gulpen Formation, as well as the Valkenburg, Gronsveld, Schiepersberg, Emael, Nekum and Meerssen members of the Maastricht Formation. The lower Maastrichtian portion is comparatively poorly preserved, being characterised by frequent reworking; only elements of the Belemnella obtusa, Belemnella sumensis and/or Belemnella cimbrica zones (the two last-named representing the traditional Belemnella occidentalis Zone) have been recorded. Belemnitella junior and Belemnitella lwowensis define the upper Maastrichtian, both first appearing in interval 4 of the Vijlen Member. At the ENCI-HeidelbergCement Group quarry, the lower/upper Maastrichtian boundary is placed at c. 5 m above the Zonneberg Horizon on benthic foraminifer evidence; strontium isotope data are in agreement. The highest portion of the Meerssen Member (uppermost IVf-6 and IVf-7) is missing from the type section; this part of the sequence is exposed at the former Curfs quarry (Geulhem), the Berg en Terblijt Horizon being equated with the Cretaceous/Paleogene (K/Pg boundary).

Description: All Campanian, Maastrichtian and Danian articulate (cladid) crinoids known to date from the extendedtype area of the Maastrichtian Stage, are described and illustrated. The geographic and stratigraphicdistribution of this unexpectedly diverse echinoderm group are documented. A total of twentygenera (three of them new) and thirty-six species (six of them new) are defined: Austinocrinus bicoronatus(von Hagenow, 1840), \xe2\x80\x98Isocrinus\xe2\x80\x99 sp., \xe2\x80\x98I.\xe2\x80\x99 lanceolatus (Roemer, 1840)?, Isselicrinus buchii (Roemer,1840), Praeisselicrinus? limburgicus (Rasmussen, 1961), Nielsenicrinus agassizii (von Hagenow, 1840) (=\xe2\x80\x98Pentacrinites\xe2\x80\x99 kloedeni von Hagenow, 1840), N. ewaldi sp. nov., Jaekelometra gr. belgica (Jaekel, 1902), J.gr. concava (Schl\xc3\xbcter, 1878) (= J. columnaris Gisl\xc3\xa9n, 1924 and including forma meijeri Rasmussen, 1961),J.? defectiva sp. nov., Placometra gr. laticirra (Carpenter, 1880), Atuatucametra annae gen. et sp. nov.,Amphorometra gr. conoidea (Goldfuss, 1839), Semiometra impressa (Carpenter, 1881), S. lenticularis (Schl\xc3\xbcter, 1878), S. saskiae sp. nov., Loriolometra retzii (Lundgren, 1875), Hertha gr. pygmea Gisl\xc3\xa9n, 1924,H. gr. plana (Br\xc3\xbcnnich Nielsen, 1913), H. gr. mystica von Hagenow, 1840 (?), Bourgueticrinus sp. 1 (aff.baculatus Klikushin, 1982c), Bourgueticrinus sp. 2, B. bruennichinielseni \xc3\x98dum, in Jessen & \xc3\x98dum, 1923,B. aff. brydonei Rasmussen, 1961, B. constrictus (von Hagenow, in Quenstedt, 1876), B. danicusBr\xc3\xbcnnich Nielsen, 1913, B. hureae (Valette, 1917), B.? suedicus (Carpenter, 1881), Democrinus? maximus(Br\xc3\xbcnnich Nielsen, 1915), Monachocrinus? gallicus Rasmussen, 1961, Cyathidium vlieksi Jagt, 1986, Applinocrinuscretaceus (Bather, 1924), Birgelenocrinus degraafigen. et sp. nov., and Veugelersia diana gen. etsp. nov. It is demonstrated that comatulids and bourgueticrinids/bathycrinids in particular show awide range of variation. Awaiting detailed biometric analyses of modern comatulid populations anda reassessment of comatulid taxonomy, for the time being the use of open nomenclature (Bengtson,1988) is favoured in these instances. Generic reassignments are proposed for Isocrinus? carinatusRoemer, 1840 [sensu Rasmussen, 1961] and Bourgueticrinus aequalis d\xe2\x80\x99Orbigny, 1841: to the cainocrinidgenus Nielsenicrinus and to the otherwise exclusively North American Late Cretaceous genus Dunnicrinus,respectively.

Description: An isolated gastropod homing scar, etched into an arcoscalpelline (cirripede) scutum, is recorded from the upper Nekum Member (Maastricht Formation, upper Maastrichtian) at the ENCI-HeidelbergCement Group quarry. This trace may be assignable to the ichnogenus Lacrimichnus Santos, Mayoral & Mu\xc3\xb1iz, that comprises etching scars produced by Neogene calyptraeid and/or capulid gastropods and ostreid bivalves from southern Spain and Portugal. However, it differs from both ichnospecies currently contained in that ichnogenus, L. bonarensis and L. cacelensis, in showing a relatively deep depression around the rim, irregularly distributed pit- and slit-like depressions, and an irregularly subcircular outline. Despite the wealth of available hard substrates (bivalves, coleoids, echinoids, etc.) and of hipponicid gastropods, such traces are exceedingly rare in the type area of the Maastrichtian Stage.

Description: All Campanian, Maastrichtian and Danian asteroids known to date from the extended type area of the Maastrichtian Stage, are described and illustrated. The geographic and stratigraphic distribution are documented. Eighteen genera (one of them new) and at least sixty-four species (eight of them new) are listed: Astropecten? sp. nov., astropectinid sp. nov., Coulonia? sp. nov., Lophidiaster? gr. punctatus/ postornatus, L. pygmaeus Spencer, 1913, Aldebarania sp. nov., Astropectinidae indet., ctenodiscid? indet., benthopectinid sp. 1 (? spp.), benthopectinid sp. 2, Metopaster alexiae sp. nov., M. aff. carinatus Br\xc3\xbcnnich Nielsen, 1943, M. continuus sp. nov., M. decipiens Spencer, 1913, M. kagstrupensis Br\xc3\xbcnnich Nielsen, 1943, M. lisannae sp. nov., M. miriamae sp. nov., M. aff. planus (Br\xc3\xbcnnich Nielsen, 1943), M. praetumidus Schulz & Weitschat, 1975, M. spencerii Br\xc3\xbcnnich Nielsen, 1943, M. gr. tumidus Spencer, 1913, M. uncatus (Forbes, 1848), M. undulatus Spencer, 1913, M. sp. 1, M. sp. 2, M. sp. 3, M. sp. 4 (aff. elegans Gale, 1987a), Parametopaster? sp., Haccourtaster aemstelensis gen. et sp. nov., Recurvaster antemammillatus sp. nov., R. mammillatus (Gabb, 1876), R. gr. radiatus (Spencer, 1913), R. spiniger sp. nov., Nymphaster alseni (Schulz & Weitschat, 1971), N. spenceri (Rasmussen, 1950), N. studlandensis (Schulz & Weitschat, 1975), N. sp., Chomataster acules Spencer, 1913, Ophryaster? maastrichtensis Umbgrove, 1925, O. magnus Spencer, 1913, O. oligoplax (Sladen, 1891), Comptoniaster peetersorum sp. nov., Crateraster anchylus (Br\xc3\xbcnnich Nielsen, 1943), C. favosus (Spencer, 1913), C. reticulatus (Schulz & Weitschat, 1981), Caletaster? sp., goniasterid sp. 1, goniasterid sp. 2, goniasterid sp. 3, goniasterid? sp. 4, goniasterid sp. 5, goniasterid sp. 6, goniasterid sp. 7, goniasterid sp. 8, Valettaster gr. ocellatus (Forbes, 1848), Stauranderaster? miliaris Br\xc3\xbcnnich Nielsen, 1943, S.? sp. (? spp.), Aspidaster? aff. senonensis (Valette, 1902), A.? sp. 1, A.? sp. 2 (aff. pistilliferus Forbes, 1848), Pycinaster aff. cornutus Rasmussen, 1945, P. magnificus Spencer, 1913, P.? aff. rosenkrantzi (Br\xc3\xbcnnich Nielsen, 1943), P. sp. 1, P. sp. 2, and asteriid sp. (? spp.). Quite a number of these must remain in open nomenclature for the time being, being based mainly on limited material. A few of the new taxa will be described elsewhere.

Description: In a series of papers describing Late Cretaceous and Early Palaeogene echinoderm faunas (exclusiveof holothurians) of the Maastrichtian type area, the present contribution comprises a detailed accountof the litho- and chronostratigraphy and biozonations of these deposits, and of localities from whichthe echinoderm material to be described stems. In subsequent papers reference will be made to thisintroductory part.

Description: The present paper is divided into two parts. In the first, all Campanian, Maastrichtian and Danian ophiuroids known to date from the extended type area of the Maastrichtian Stage, are described and illustrated. The geographic and stratigraphic distribution of this diverse echinoderm group are documented. A total of twenty-one genera (one of them new) and thirty-seven species (seven of them new) are recorded from the Campanian-Danian of Li\xc3\xa8ge-Limburg and the Aachen area (Germany). The following taxa are new: Ophiocten? yvonnae sp. nov., Stegophiura? trispinosa sp. nov., Deckersamphiura inusitata gen. et sp. nov., Ophiarachna? martinblomi sp. nov., Ophiolepis? falsa sp. nov., Ophiomusium lux sp. nov., and Mesophiomusium decipiens gen. et sp. nov. Additional species, recorded here in open nomenclature, may prove to be new as well, but limited material precludes their formal naming. \nMany ophiuroid species from Li\xc3\xa8ge-Limburg are also known from the Lower Maastrichtian of R\xc3\xbcgen and M\xc3\xb8n (Denmark). In general, material from those localities is much better preserved, which is why type specimens of additional new taxa have been selected from samples collected there. In the second part of the present paper a total of twenty-four new species and one new genus are described: Ophiosmilax? alternatus sp. nov., Asteronyx? spinulosa sp. nov., Ophiomyxa? curvata sp. nov., Ophiomyxa? rhipidata sp. nov., Ophioscolex? clivulus sp. nov., Ophioscolex? cretaceus sp. nov., Ophiacantha? punctata sp. nov., Ophiacantha? rugosa sp. nov., Ophiacantha? striata sp. nov., Sinosura jasmundensis sp. nov., Hemieuryale? parva sp. nov., Amphiura? plana sp. nov., Ophiothrix? bongaertsi sp. nov., Ophiothrix? cristata sp. nov., Ophiothela? semirotunda sp. nov., Ophiactis? sulcata sp. nov., Ophiocoma? ishidai sp. nov., Ophioderma? radiatum sp. nov., Ophiolepis? granulata sp. nov., Ophiolepis? linea sp. nov., Ophiomusium biconcavum sp. nov., Ophiomusium sentum sp. nov., Ophiomusium sinuatum sp. nov., and Mesophiomusium moenense gen. et sp. nov. Four additional species (Trichaster? sp., Ophiacantha? sp., Sinosura sp., and S. aff. schneideri Kutscher, 1987) are left in open nomenclature; these may prove to be new as well, but not enough material is currently available to erect new species upon. \nPreviously described ophiuroid species, some of which are here reassigned to other genera, in all of these faunas include: Asteronyx? simplex A.H. M\xc3\xbcller, 1950, Trichaster? ornatus (Rasmussen, 1950), Ophiomyxa? jekerica (Berry, 1938), Ophiacantha? danica Rasmussen, 1952, Stegophiura? hagenowi (Rasmussen, 1950), Felderophiura vanderhami Jagt, 1991, Ophioplinthaca? fuerstenbergii (J. M\xc3\xbcller, 1847), Ophiocoma? senonensis (Valette, 1915), Ophiocoma? rasmusseni Hess, 1960b, Ophioderma? substriatum (Rasmussen, 1950), Ophiotitanos serrata (Roemer, 1840), and Ophiomusium granulosum (Roemer, 1840). Ophiomusium subcylindricum (von Hagenow, 1840) and O. danicum Br\xc3\xbcnnich Nielsen, 1926 are considered to be junior synonyms of O. granulosum. \nWith very few exceptions, species assignment to extant genera is fraught with difficulties, even in those cases where more or less complete discs with arms attached are available. Most of our taxa are based on dissociated ossicles, or portions of arms at best, which are preferentially placed in the nomipp nal genera of the various ophiuroid families. Despite this present paper demonstrates that Late Cretaceous-Early exceeds previous estimates, and that the white chalk facies benthic inhabitation than assumed by earlier authors.

Description: A small lot of latest Cretaceous brittlestars from the Maastrichtian type area, contained in the Binkhorst [van den Binkhorst] Collection at the Museum f\xc3\xbcr Naturkunde in Berlin, is restudied and, in part, illustrated for the first time. Presumably, these thirteen specimens represent only a portion of the ophiuroid material referred to in two papers by Binkhorst van den Binkhorst, both published in 1859, because all are assignable to two species which are common only in the Nekum and Meerssen members of the type Maastrichtian, namely Felderophiura vanderhami Jagt, 1991, and Ophiomusium lux Jagt & Kutscher in Jagt, 2000. Brittlestar material from lower levels within the Maastricht Formation (i.e., Valkenburg, Gronsveld, Schiepersberg and Emael members) referred to by Binkhorst has not been traced. Alternatively, Binkhorst\xe2\x80\x99s original records could have been based on specimens contained in collections of his contemporaries, such as Joseph de Bosquet and Casimir Ubaghs. In most, if not all, of such cases, representatives of Ophiomusium gr. granulosum (Roemer, 1841) [sensu Jagt, 2000] are involved. Based on our own observations in the Maastricht area, Binkhorst\xe2\x80\x99s specimens of F. vanderhami and O. lux must have originated from the upper Meerssen Member where these two species are locally common. In fact, mostly isolated discs are preserved in the present lot, with only some retaining proximal arm portions, which suggests these were picked from sieving residues after bulk sample processing. More or less complete specimens of both species have also been collected recently, but these are confined to bedding planes. Although preservation is mediocre, diagnostic features of both F. vanderhami and O. lux are readily apparent.

Description: All Campanian, Maastrichtian and Danian echinoids known to date from the extended type area of the Maastrichtian Stage are listed and, with a few exceptions, also illustrated. The geographic and stratigraphic distribution of these echinoderms are documented. A total of 55 (sub)genera and 119 (sub)species (inclusive of formae), two of which are new, are recognised. A number of taxa are reassigned, while others have to remain in open nomenclature for the time being. Recorded for the first time from the area are representatives of Hagenowia and Zeuglopleurus, as well as juvenile specimens of Hemipneustes striatoradiatus. Cidaris gigas (= Temnocidaris (Stereocidaris) gigas) is accepted as a valid species. The name Cyphosoma rutoti is shown to be based on the spines of C. corneti, now reassigned to Trochalosoma?. New are Plagiochasma lammersmaxi Jagt & van der Ham, sp. nov. and Micropsis? caementum Jagt & van der Ham, sp. nov. The scope of the present paper is taxonomic and stratigraphic; the palaeobiology and palaeoecology of the echinoid faunas will be discussed in a forthcoming paper, part 6 in the present series.