Regeneration time and morphology of the inhalant siphon of Donax denticulatus Linnaeus, 1758 (Bivalvia: Donacidae) after amputation

MILOSLAVICH, P. A.; PENCHASZADEH, P. E.; CARBONINI, A. K.; SCHAPIRA, D.

JOURNAL OF SHELLFISH RESEARCH

NATL SHELLFISHERIES ASSOC

Año: 2004 vol. 23 p. 447 - 450

0730-8000

To study the process of regeneration and its effect on the morphology of the inhalant siphon of a tellineacean bivalve,Donax denticulatus, individuals were artificially amputated and placed in aquaria under laboratory conditions, in the absence ofpredators. After amputation, two individuals were sacrificed twice a day (9 AM and 5 PM) during a 9- day period, and their siphons wereexamined in the microscope. Within the first 24 hours after amputation, the process was slow, and only the rudiments of the primarytentacles were visible. However, between the second and the third day a fast transformation of the siphon was observed, withregeneration of secondary and tertiary tentacles. The siphon was fully regenerated on the fifth day after amputation. One month later,the siphon showed the same aspect than at the fifth day. Despite the delay observed in the regeneration of the siphon within the first24 hours after amputation, probably due to physiologic constrains associated with the lack of well developed tentacles, regenerationshowed to be a fast process. Development of primary and secondary tentacles must therefore play an important role in providing basicfunctionality to the siphon, as well as to the whole organism.