Just out @ Alcheringa
Three new species of the extinct echinoid genus Monostychia Laube, 1869 are described from Western Australia. All are from the middle Miocene Colville Sandstone of the Eucla Basin and have historically been referred to this genus without description. These new taxa differ from previously described Monostychia species in several morphological features, such as size and shape but also in the number of post-basicoronal interambulacral plates developed in the oral paired interambulacrum, a feature considered taxonomically important at both genus and species level for clypeasteroids. The number of ambulacral plates in the paired and unpaired oral regions is also considered a potentially diagnostic taxonomic feature for this genus; it is concluded that the oral ambulacral plate count, particularly that of the unpaired ambulacrum III, is at least as useful a taxonomic feature as the oral interambulacral plate count.
Read it here:
Latest posts by Lurdes Fonseca (see all)
- Just out | First record of insects in lignite-bearing formations (upper Eocene) of the central German Leipzig Embayment @ PalZ - June 28, 2017
- Just out | Goniatites sphaericus (Sowerby, 1814), the archetype of Palaeozoic ammonoids: a case of decreasing phenotypic variation through ontogeny @ PalZ - June 28, 2017
- Just out | Brachiopods: origin and early history @ Palaeontology - June 28, 2017