First record of a trophonema in black corals (Cnidaria: Antipatharia)
The gametes of many groups of anthozoans contain a funnel-shaped cluster of specialized cells that facilitate the transport of nutritive substances, known as the trophonema. This structure has been found within all orders of anthozoans, with the exception of pennatulaceans, scleractinians, and antipatharians, the latter of which are commonly known as black corals. Based on the histological study of eight specimens of the black coral Dendrobathypathes grandis Opresko (Zool Med Leiden 76(22):411–442, 2002) from the southwestern Atlantic, we report for the first time the presence of a trophonema within the order Antipatharia. A trophonema was found only in oocytes from one of the seven female specimens studied. Since D. grandis contains the largest oocytes among antipatharians that have been studied to date, it remains unknown whether the presence of a trophonema is an exceptional case, or whether these structures have simply been overlooked in other black corals.
KeywordsArgentina Histology Oocyte Reproduction Southwestern Atlantic
Many thanks to the captain and crew of the O/V Puerto Deseado for their assistance and to the anonymous rewires for their valuable comments. This work was supported by a PICT 2013-2504 Grant to PP and a PADI foundation Grant to DL. Many thanks to Cristina Damborenea and Florencia Arrighetti for comments on the histology interpretation.
Compliance with ethical standards
Conflict of interest
On behalf of all authors, the corresponding author states that there is no conflict of interest.
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