PaleoDB taxon number: 222533
Named by Carter.
Original description: Cephalis small, dome-shaped, with small apical horn, circular in axial section. Thorax, abdomen and first abdominal chamber trapezoidal in outline with small polygonal pore frames. Final post-abdominal chamber marginally inflated, composed of medium-sized polygonal pore frames. No significant break between first and final post-abdominal chambers. Terminal tube narrow, imperforate or with very small pore frames randomly distributed.
Original remarks: Whalen & Carter (1998) originally included this species with Katroma irvingi Whalen and Carter, a species with widely ranging variation mainly in the size of the final post abdominal chamber. Recent studies of the Pliensbachian fauna, however, indicate that K. irvingi s. s. does not range above the Sinemurian, but the successor species, Katroma elongata n. sp., does and is abundant through most of the Pliensbachian. For this reason, it has been described as a separate species.
Syringocapsa coliforme Hori (1988) differs from Katroma elongata n. sp. in having a more massive apical horn and a narrower abdominal profile.
Etymology: Latin (adj.) elongatus-a-um elongate.
Full reference: S. Gorican, E. S. Carter, P. Dumitrica, P. A. Whalen, R. S. Hori, P. De Wever, L. O'Dogherty, A. Matsuoka, and J. Guex. 2006. Catalogue and systematics of Pliensbachian, Toarcian and Aalenian radiolarian genera and species 446
Sister taxa: Katroma angusta, Katroma aurita, Katroma bicornus, Katroma brevitubus, Katroma clara, Katroma hullae, Katroma inflata, Katroma inflatio, Katroma irvingi, Katroma milloti, Katroma neagui, Katroma pinquitudo, Katroma regina, Katroma sinetubus, Katroma tetrastyla, Katroma westermanni
Type specimen: GSC 111721. Its type locality is Rennell Junction, Graham Island; GSC loc. C-080612, which is in a Pliensbachian marine limestone in the Ghost Creek Formation of Canada.
Ecology: passively mobile planktonic omnivore