SHIRLEY,T.C.: Priapulida Priapulida are a monophyletic group of marine, benthic worms with a retractile introvert for locomotion and feeding and a chitinous cuticle which is shed periodically. A mixture of bilateral and radial symmetry is present. The integument may bear many unique structures, including scalids, flosculi, setae, hooks, trunk scalids, tubercles and tumuli. A spacious […]

Near, T.J.: Phylogeny of the Acanthocephala and insights to the evolution of parasitism The Acanthocephala are a lineage of obligate helminth parasites of arthropods and vertebrates. Previous phylogenetic investigations utilizing ribosomal and protein coding genes indicate that the Acanthocephala is nested within the Rotifera. This is the only majorparasitic lineage with an indentified free-living sister-taxon. […]

GRENIER, J.K.: Minor Phyla Fill the Gaps: Priapulida and Onychophora The advent of comparative molecular databases has generated new hypotheses about animal phylogeny that are reshaping our understanding of animal evolution. For example, the bilaterian phyla are now often grouped into three major clades, the deuterostomes, the lophotrochozoans, and the ecdysozoans. The Ecdysozoa include several […]

HIGGINS, R.P.; NEUHAUS, B.*: Kinorhyncha The Kinorhyncha are protostome, bilaterally symmetrical, exclusively free-living marine animals, less than 1 mm long, and ecologically part of the meiofauna, either endo- or mesobenthic, and euryhadyl. They occur throughout the world, generally in sedimients but sometimes associated with plants or other animals. Kinorhynchs are segmented as evidenced by their […]

HALANYCH, K.M.*; McHUGH, D.; Dahlgren, T.G.: Evidence that some lesser-known “phyla” are annelids In traditional schemes, the Annelida has been classified as the Polychaeta, Oligochaeta, and Hirudinea (the last two comprising the Clitellata). However, recent analyses indicate that annelids are much more diverse than traditionally believed, and that polychaetes are a paraphyletic group. Specifically, some […]

NELSON, D.R.: Current status of the Tardigrada The Tardigrada are lobopodous micrometazoans that occupy a diversity of niches in marine, freshwater, and terrestrial environments throughout the world. Some have a cosmopolitan distribution, while others are endemic. About 900 species have been described thus far, but many more species are expected as additional habitats are investigated. […]

KRISTENSEN, R.M.: An Introduction to Loricifera, Cycliophora, and Gnathometazoa Adult loriciferans are bilaterally symmetrical marine metazoans between 108-485 microns. The body is divided into five regions: mouth cone, head (introvert), neck, thorax and abdomen. The first description of a loriciferan (Nanaloricus mysticus) was in 1983 from specimens collected from shell gravel off the coast of […]

FERRY-GRAHAM, L.A.*; WAINWRIGHT, P.C.: Using Functional Morphology to test General Ecological Theory Even before Hutchinson defined what he coined the ‘fundamental niche’, researchers have been striving to understand what it is that makes species different, and what allows them to survive in the time and space that they do. Since that time, many theories have […]

KELLY, D. A.: The Functional Morphology of Penile Erection: Tissue Designs That Make the Floppy Stiff Functional morphology focuses on how biological structures work in the natural world; the specifics of how any structure works depends in part on both the mechanical properties of its materials and how those materials are arranged within the structure. […]

WALKER, J.A.: Swimming in air, flying under water: Physical constraints on the design of oscillating wings, fins, legs, and feet at intermediate Reynolds numbers Why do some animals swim by rowing appendages back and forth while others fly by flapping them up and down? One answer lies in the sharply divergent physical environments encountered by […]