“Scalibregma inflatum, H. Rathke, var. (Pl. XLIV. figs. 3, 4 ; Pl. XXIIA. fig. 21).
Habitat.—Dredged in considerable abundance at Station 141 (between Prince Edward Island and Kerguelen), December 17, 1873 ; lat. 34° 41' S., long. 18° 36' E. ; depth, 98 fathoms ; bottom temperature 49°·5, surface temperature 65°·5 ; sea-bottom, green sand.
Apparently the same form was trawled at Station 169 (off the north-west corner of New Zealand), July 10, 1874 ; lat. 37° 34' S., long. 179° 22' E. ; depth, 700 fathoms ; bottom temperature 40°·0, surface temperature 58°·2 ; sea-bottom, blue mud.
The specimens are all much smaller than the European Scalibregma inflatum, the longest measuring about 18 mm., with a breadth at the anterior thickened region of nearly 4 mm.
When compared with the European form of similar size, the foreign species has a more fusiform outline and much less of the inflation anteriorly. The branchiæ are similar, but in the Norwegian examples these are longer. In both the latter and the British specimens a prominent and continuous fold occurs behind the head (separated by a sulcus) ; but in the Challenger form the head has a greater antero-posterior diameter, and posteriorly there are two elevated surfaces or papilla (Pl. XLIV. fig. 3). The only difference in regard to the tail is the apparent increase in the length of the cirri towards the tip, but in this respect so much depends on the state of the preparations that little reliance can be placed on it. The tessellated dorsal regions of the respective forms are very similar.
The cirri on the posterior feet seem to be somewhat longer. The spikes on the inner edge of the forks of the bristles (Pl. XXIIA. fig. 21) are smaller, the inferior bristles showing the latter feature better than the superior. Both British and foreign bristles have unequal limbs to the fork.
The curved bodies observed in the lamellæ of the feet are probably homologous with those described by Kölliker and Greeff in Ephesia (Sphærodoram).
The intestine is distended with sandy mud, amongst which are spicules of sponges, Foraminifera, and small Gregarin, the latter being probably parasitic in the Annelid.
In transverse section the body-wall posteriorly agrees with the structure in Scalibregma inflatum, the nerve-cords lying outside the circular muscular coat, and having externally the hypoderm and cuticle. The oblique muscles meet in the middle line above the circular coat.”
(McIntosh, 1885)
Scalibregma inflatum, also known as T headed worm, is a burrowing marine polychaete. It is a cosmopolitan species that can be found from the Arctic to Antarctica, although most probably several species are confounded.[1]
Up to 6 cm long with an orange body with 50–60 segments. Body is composed of a wide anterior part of segments 15–17 and a long slim posterior part. Prostomium rectangular shaped with two lateral horns making it appear as a T. peristomium without chaetae. Parapodia small and oval at first increasing in size from segments 16–18. Four pairs of branching gills dorsally on 2-5 segment with chaetae.[2][3]
Mainly found in muddy substrate, but can also be found in sand and between stones and shells. S. inflatum is a deposit feeder. During the spawning period S. inflatum undergoes epitoky.[2][3]
Scalibregma inflatum is found within the polychaete family Scalibregmatidae.[4] The genus Scalibregma is composed of 15 different species.[5]
Scalibregma inflatum, also known as T headed worm, is a burrowing marine polychaete. It is a cosmopolitan species that can be found from the Arctic to Antarctica, although most probably several species are confounded.
