Layers of body wall musculature either two (outer circular, inner longitudinal) or three (outer circular, middle longitudinal, inner circular); dermis of hyaline connective tissue; central nervous system either in inner longitudinal musculature or external to body wall muscles.
Source: Gibson, 1982.
The following taxa of this order occur in the region:
Family Carinomidae
Genus Carinoma
Family Cephalothricidae
Genus Cephalothrix
Genus Procephalothrix
Family Hubrechtidae
Genus Hubrechtella
Family Tubulanidae
Genus Callinera
Genus Carinina
Genus Tubulanus
Callinera buergeri
Carinina arenaria
Carinina coei
Carinoma armandi
Cephalothrix arenaria
Cephalothrix linearis
Cephalothrix rufifrons
Hubrechtella dubia
Procephalothrix filiformis
Tubulanus annulatus
Tubulanus linearis
Tubulanus polymorphus
Tubulanus superbus
Tubulanus theeli