Thalassema

• Main Author: Biseswar, Ramlall
• Format: Other/Unknown Material
• Language: unknown
• Published: 2009
• Subjects: Biodiversity; Taxonomy; Animalia; Echiura; Polychaeta; Echiuroidea; Echiuridae; Thalassema; Antarc*
• Online Access: https://zenodo.org/record/6225242; https://doi.org/10.5281/zenodo.6225242

Key to the species of Thalassema from the Atlantic Ocean 1 Gonoducts two pairs. 2 - Gonoducts one pair. 3 2 Gonostome fan-shaped; papillae arranged in transverse series in middle region of trunk. T. philostracum - Gonostomal lips semicircular and frilled, papillae largest and most densely packed in posterior region of trunk, not arranged in transverse series. T. thalassemum 3 Anal vesicles lacking; microscopic papillae located only in middle region of trunk. T. antarcticum - Anal vesicles present. 4 4 Gonostomal lips folded or crumpled; rectal caecum absent. T. elapsum - Gonostomal lips not folded or crumpled. 5 5 Interbasal muscle absent; gonostomes large; papillae more closely packed at anterior and posterior ends of trunk. T. arcassonense - Interbasal muscle present. 6 6 Integument thin and transparent; papillae small white specks scattered over trunk, more closely arranged at posterior end; rectal caecum absent. T. diaphanes - Integument opaque; papillae prominent, unequal in size, the larger ones scale-like and bent forwards; rectal caecum present. T. hartmani Published as part of Biseswar, Ramlall, 2009, The geographic distribution of echiurans in the Atlantic Ocean (Phylum Echiura), pp. 17-30 in Zootaxa 2222 on page 22, DOI:10.5281/zenodo.190138