Reproductive biology of the Antarctic “sea pen” Malacobelemnon daytoni (Octocorallia, Pennatulacea, Kophobelemnidae)

Figures & data

Fig. 1 Map of the study site. (a) Location of Potter Cove on King George Island (Isla 25 de Mayo), South Shetland Islands. (b) Sampling zone.

Fig. 2 External morphology of Malacobelemnon daytoni. (a) Tips of colonies showing axial rod. (b) Detail of M. daytoni tips showing the exposed axial rod. (c) Lower rachis and peduncle. (d) Details of the peduncle. (e) Autozooid in the apical part of the colony with mature oocytes.

Fig. 3 Relative frequency of oocytes’ diameter in polyps of Malacobelemnon daytoni (100 colonies, n = 5360).

Fig. 4 Relationship between length (mm) and index of fecundity of Malacobelemnon daytoni (number mature oocytes, mm⁻²).

Fig. 5 Relationship between length of fertile region (rachis) with increasing colony length in Malacobelemnon daytoni.

Fig. 6 Malacobelemnon daytoni. (a) Light microscopic section through the longitudinal canal showing early growth oocytes (EO) grouped in cluster (CL). (b) Light microscopic section through the longitudinal canal showing growth oocytes. (c) Mature oocyte in longitudinal canal showing follicle cells (FC).

Fig. 7 Mean oocyte stages frequency distribution of Malacobelemnon daytoni in each of the colony sections: basal, middle and apical (n = 671 for basal; n = 3786 for middle and n = 884 for apical) Vertical bars indicate±SD. Letters indicate groups of the a posteriori analysis (p < 0.05).

Table 1 Sexual pattern of Pennatulacea, arranged in chronological order of the published source.

Source	Species	Locality	Sexual pattern	Feret diameter of mature oocytes (µm)	Spawning	Oocytes’ number	Greater colony length (mm) and sexual maturity	Depth (m)
1973)	Ptilusarcus guerneyi	Alki Point, Seattle, USA (47° 34′N)	Gonochoric	500–600	Late March	200 000 (per season)	–	Shallow
1992)	Kophobelemnon stelliferum	porcupine seabight, SW Ireland (50° 01′N)	Gonochoric	800	No seasonality	–	250	1150
1995)	Umbellula lindahli	porcupine seabight, SW Ireland (50° 01′N)	Gonochoric	–	–	–	–	650–3850
1998)	Pennatula aculeata	Gulf of Maine, USA (43° 25'N; 68° 47′W)	Gonochoric	880	Continuous spawning	–	Probably 70	113–231
2004)	Renilla koellikeri	Southern California, USA	Gonochoric		May–July	–		Subtidal
2005)	Virgularia juncea	Chitou Bay, Taiwan Strait (23° 38′N)	Gonochoric	200–300	July–September	46 000 (50 cm cl) 87 000 (70 cm cl)	700 (50)	0.5–1
2008)	Pennatula phosphorea	Lismore Island, Scotland (56°, 32′N)	Gonochoric	>500	July and/or August	7895 (9, 6 cm cl) 53 534 (12 cm cl)	120 (88)	18–19
2009)	Funiculina quarangularis	Lismore Island, Scotland (56°, 32′N)	Gonochoric	>800	October–January	500–2000 (per cm^2)	–	18.9–24.3
2009)	Anthoptilum murrayi	SW Atlantic, Brazil (13° to 22°S)	Gonochoric	1200	Continuous	up 35 918 (per colony)	580 (females) 640 (males)	1300–1799
Lopes et al. (2012)	Veretillum cynomorium	Sado Estuary, Portugal	Gonochoric	967	July	up 40 (per polyp)	–	13–91
Present study	Malacobelemnon daytoni	Potter Cove, King George Island, Antarctic (62°14′S)	Gonochoric	350	–	22 (1.5 cm cl) 745 (11 cm cl)	110 (15)	10–30

Chia F.S, Crawford B.J. Some observations on gametogenesis, larval development and substratum selection of the sea pen Ptilosarcus guerneyi. Marine Biology. 1973; 23: 73–82.

 Web of Science ®Google Scholar

Rice A.L, Tyler P.A, Paterson G.J.L. The pennatulid Kophobelemnon stelliferum (Cnidaria: Octocorallia) in the porcupine seabight (north-east Atlantic Ocean). Journal of the Marine Biological Association of the United Kingdom. 1992; 72: 417–434.

 Web of Science ®Google Scholar

Tyler P.A, Bronsdon S.K, Young C.M, Rice A.L. Ecology and gametogenic biology of the genus Umbellula (Pennatulacea) in the North Atlantic Ocean. Internationale Revue der gesamten Hydrobiologie. 1995; 80: 187–199.

 Google Scholar

Eckelbarger K.J, Tyler P.A, Langton R.W. Gonadal morphology and gametogenesis in the sea pen Pennatula aculeata (Anthozoa: Pennatulacea) from the Gulf of Maine. Marine Biology. 1998; 132: 677–690.

 Web of Science ®Google Scholar

Tremblay M.E, Henry J, Anctil M. Spawning and gamete follicle rupture in the cnidarian Renilla koellikeri: effects of putative neurohormones. General and Comparative Endocrinology. 2004; 137: 9–18.

 PubMed Web of Science ®Google Scholar

Soong K. Reproduction and colony integration of the sea pen Virgularia juncea. Marine Biology. 2005; 146: 1103–1109.

 Web of Science ®Google Scholar

Edwards D.C.B, Moore C.G. Reproduction in the sea pen Pennatula phosphorea (Anthozoa: Pennatulacea) from the west coast of Scotland. Marine Biology. 2008; 155: 303–314.

 Web of Science ®Google Scholar

Edwards D.C.B, Moore C.G. Reproduction in the sea pen Funiculina quadrangularis (Anthozoa: Pennatulacea). Estuarine Coastal and Shelf Science. 2009; 82: 161–168.

 Web of Science ®Google Scholar

Pires D.O, Castro C.B, Silva J.C. Reproductive biology of the deep-sea pennatulacean Anthoptilum murrayi (Cnidaria, Octocorallia). Marine Ecology Progress Series. 2009; 397: 103–112.

 Web of Science ®Google Scholar

Lopes V.M, Baptista M, Pimentel M.S, Repolho T, Narciso L, Rosa R. Reproduction in Octocorallia: synchronous spawning and asynchronous oogenesis in the pennatulid Veretillum cynomorium. Marine Biology. 2012; 8: 893–900.

 Web of Science ®Google Scholar