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Two new species of cornulitids, Cornulites zatoni sp. nov. and Cornulites vilcae sp. nov., are described from the lower part (Sandbian) of the Calapuja Formation of south-western Peru. Late Ordovician cornulitid diversities of Peru (Gondwana) and Estonia (Baltica) are similar. Aggregative growth form dominates among the cornulitids of the Sandbian of Peru. Multiple oriented C. zatoni sp. nov. specimens on a strophomenid brachiopod likely represent a syn vivo encrustation. Cornulitids from the Sandbian of Peru differ from those known from the Sandbian of Baltica. C. zatoni sp. nov. possibly also occurs in the Late Ordovician of Laurentia. [ABSTRACT FROM AUTHOR]

The first Furongian trilobites are described herein from the Cambrian of the Cantabrian Zone, NW Spain. They were collected during the construction of the "Túnel Ordovícico del Fabar" from the shales of "El Fabar Beds" in the La Matosa member of the Barrios Formation. The assemblage includes the aphelaspidine genus Maladioidella, with a specimen identified as M. cf. colcheni, a species previously known from Sierra de la Demanda (Spain), and possibly Sardinia and Oman. Fragments of an indeterminate olenid trilobite and phyllocarid crustaceans have also been recorded. Based on the acritarch assemblage, these beds are considered as late Jiangshanian or earliest Stage 10 of the Cambrian System. The ichnofossil Cruziana semiplicata has also been collected in the tunnel from the upper part of the Ligueria Member (Tremadocian) of the Barrios Formation, clearly postdating the occurrence of Maladioidella colcheni, its supposed tracemarker according to some authors. The separate record of both taxa (a Furongian trilobite and a Cambro-Ordovician trace fossil) does not support this statement, so their relationship would be refuted in this case. [ABSTRACT FROM AUTHOR]

The family Harknessellidae Bancroft, 1928 (Orthida, Dalmanellidina) was designed to embrace an assemblage of species referred previously to Harknessella Reed, 1917, and included five genera known mainly from the Middle and Upper Ordovician of England. Herein, we suggest reassigning to this family the genus Cacemia Mitchell, 1974, widespread in the middle Darriwilian (upper Middle Ordovician) of the Iberian and Armorican massifs. Since its designation, Cacemia was placed among the dalmanellidin heterorthids, in spite of its strongly mucronate hinge line, which is totally unknown within this Mediterranean family. A new harknessellid has been identified from the upper Darriwilian beds of the Central Iberian Zone (Central Spain): Isabelella fascicostellata Reyes-Abril & Villas gen. et sp. nov. It is similar to Horderleyella Bancroft, 1928 for its coarsely fascicostellate radial ornamentation and obtuse cardinal angles, although its convexoplane to convexoconcave profile allows discrimination from the typically dorsibiconvex Horderieyella. A phylogenetic analysis of the family places both Cacemia and Isabelella in basal positions of their clades, which fits with their early stratigraphic record. Based on our study, the family Harknessellidae appears to have originated in the high latitude Mediterranean margins of Gondwana during pre-Darriwilian times, before the detachment of Avalonia from Gondwana. The family reached its highest diversification in Avalonia throughout the Late Ordovician, keeping connections with the Mediterranean and Proto-Andean margins of Gondwana, as well as with the mid-latitude palaeocontinents of Baltica and South China. [ABSTRACT FROM AUTHOR]