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Parabolina frequens argentina (Kayser) (Trilobita,Olenidae) is a guide fossil occurring indifferent assemblages and lithologies of the upperCambrian (Furongian) of northwestern Argentina.The black and dark grey shales of theLampazar Formation at sierra de Cajas and theSanta Rosita Formation (lower part) at Iruya andAlfarcito (Jujuy and Salta provinces) containnumerous well-preserved specimens at differentstages of development. The juveniles representanaprotaspis, metaprotaspis and degrees 0-11meraspis. The latter exhibit a high variabilityrelated with the pattern of glabellar furrows andlobes, the sagittal length of the thoracic segments,the splay and length of the genal and thoracicspines, the relative width of the axis, andthe relative development of the axial tubercles.As in other species of Parabolina, the meraspidstages of P. frequens argentina do not formwell-defined instar groupings. Besides, in theadult specimens the length of the anterior cephalicborder and the preglabellar field are alsovariable characters. The hypostome is characterizedby having almost completely reduced anteriorwings; it lies in close association with theventral doublure (conterminant condition). Althoughsome authors suggested that P. frequensargentina and P. frequensfrequens (Barrande)could be synonyms, these taxa differ in havingdistinctive pygidia and hypostomes. Many exoskeletalconfigurations can be interpreted as exuviae.From a functional point of view, it islikely that the genal and macropleural spines onthe 8th thoracic segment supported the body ofthe trilobite when resting on the sea floor. Theexoskeleton can be reconstructed in two alternativepostures, the "alert" and "relaxed" attitudes.2008040396西 班 牙 莫 雷 纳 山 脉 下 寒 武 统 底 部 新 的 下Ovetian 阶 三 叶 虫 = New lower Ovetian trilobites(low lower Cambrian) from Sierra Morena(Spain). ( 其 他 ). Linani E; Gozalo R; Alvarez ME D. Ameghiniana, 2008, 45(1): 123-138Trilobites from two lower Ovetian (low lowerCambrian) localities in Sierra Morena (south ofSpain) are described. Serrania palaciosi nov. sp.and Serrania? gordaensis nov. sp. come from thewestern locality (Alconera). New specimens ofSerrania verae Linan Guijarro, 1978 come fromthe eastern locality (Sierra de Cordoba). Theontogenetic study of S. verae suggests that thisspecies evolved from S. palaciosi. The new materialallows us to include the genus Serraniawithin the new subfamily Serrinae definedherein, belonging to the family Bigotinidae. Weinclude also two more genera with a lateral spinein the glabella, Hupetina and Sdzuyia. Accordingto its stratigraphical position and the associatedtaxa, we can determinate that S. verae belongsto the Lemdadella linaresae Zone, correspondingto the lower part of the archaeocyatidsZone III. On the basis of stratigraphic and phylogeneticcriteria, S. palaciosi nov. sp. and S.?gordaensis nov. sp. from Alconera belongprobably to the Zone I of archaeocyathids. Someunclassifiable trilobite fragments have been alsofound in the Zone I of archaeocyathids at theOvetian stratotype in Sierra de Cordoba, belowthe trilobite zone of Bigotina bivallata (which isequivalent to the trilobite Zone 0, or EofallotaspisZone, of Morocco). The new species definedherein are, up to now, the oldest trilobitesdescribed from Gondwana.棘 皮 动 物2008040397密 西 西 比 亚 纪 海 百 合 Gilbertsocrinus tuberosus的 固 着 器 = The Holdfast of Gilbertsocrinustuberosus (Mississippian, Crinoidea). ( 英 文 ).Ausich W I; Hollis K A. Canadian Journal ofEarth Sciences, 2008, 45(2): 135-140Gilbertsocrinus is a common Middle Devonianto Lower Mississippian crinoid fromEurope, North America, and China. This crinoidhas several very unusual features, such as tegmenappendages, minute arms, a very flexiblecolumn, and an unusual holdfast. It is demonstratedthat a bulbous holdfast does not exist inGilbertsocrinus, as previously interpreted. Gilbertsocrinusis an unusual crinoid; however, ithas a distal coil rather than a tuberous holdfast.2008040398土 耳 其 中 部 新 的 中 泥 盆 统 gasterocomid 类 海百 合 及 Gasterocomidae 科 的 厘 定 = A newMiddle Devonian gasterocomid crinoid fromcentral Turkey and revision of the Gasterocomidae.( 英 文 ). Webster G D; Yilmaz I; Kozlu H.palaeoworld, 2008, 17(1): 12-20A juvenile cup, disarticulated arm plates, andcolumnals of the crinoid Arachnocrinus sarizensisn. sp. are described from the Eastern TaurusMountains of central Turkey. This is the firstPaleozoic crinoid based on a cup and arm platesreported from Turkey. Suggested revision of theGasterocomidae includes transfer of Arachnocrinusand Ancyrocrinus to the family andrejection of Kopficrinus from the family. Thestratigraphic range of Arachnocrinus is extendedupward into the Middle Devonian from the EarlyDevonian. The Devonian of Turkey is of specialinterest because it includes Laurasian andGondwanan components on different tectonicblocks. The paleogeographic range of Arachnocrinusis extended from the North Americanplate onto the Anatolian block, which wouldhave been located on the southern edge of thePaleotethys Sea in the Middle Devonian in a123