Discovering Mediterranean black coral forests: Parantipathes larix (Anthozoa: Hexacorallia) in the Tuscan Archipelago, Italy

Figures & data

Figure 1. Sampling sites. Location of the studied shoals off the coasts of Montecristo Island (Tuscan Archipelago, Tyrrhenian Sea, Italy).

Figure 2. High-resolution bottom topography. Multibeam maps of the studied shoals.

Table I. Summary of the sampling data for the four study areas.

Site	Coordinates	No. dives	No. frames	No. HD photos	Depth range	No. P. larix	Area (m^2)
S1	42°135N	1	117	17	108–121	6	394
	10°135E
S2	42°170N	2	82	17	146–197	179	310
	10°175E
S3	42°180N	1	50	0	96–117	1	187
	10°145E
S4	42°250N	2	122	256	127–170	254	433
	10°040E
Total		6	371	290	100–200	440	1324

Figure 3. Parantipathes larix. A, specimen with a greatly ramified corallum showing branches directed upwards and downwards. B, monopodial specimen with no lateral branches. C, pluriserial arrangement of the pinnules around the main stem. D, knots of pinnules around the central stem. E, groups of small spines on the stem. F, spines in three portions of a pinnule, from base to apex. G, close-up view of the pinnular spines. H–I, photographs of living polyps showing the typical white coloration. J, fertile female polyp (white arrow indicates eggs). K, spirocyst. L, basitrich isorhiza. M, mastigophore. Scale bars: A, B, 10 cm. C, D, H, 1 cm. I, 0.5 cm. E, F, J, 1 mm. G, 0.2 mm. K–M, 5 μm.

Figure 4. Shape of the corallum and associated fauna of Parantipathes larix. A–B, branched specimens of P. larix showing distinct knots of lateral ramifications. C, pair of Anamathia rissoana covered by unidentified athecate hydroids. D, unidentified species of ostracod living among the coral ramifications. E, dead basal portion of the stem covered by hydroids and Filograna spp. F, school of Macroramphosus scolopax swimming among the coral colonies. Scale bars: A, B, E, F, 10 cm. C, 5 cm. D, 0.5 cm.

Figure 5. Species composition of the four studied target communities (number of colonies or specimens m⁻² ± SE).

Figure 6. Patches of Parantipathes larix. A–C, patches of tall, poorly branched colonies on S2 bent towards the inclined silted bottom. D–E, dense forests of P. larix on flat rocky elevations in S4. F–J, examples of coral patches on the Montecristo shoals. K, branched specimen from the Gulf of St. Eufemia (130 m depth). L, colony from a rocky shoal off Carloforte (Sardinia), 140 m depth. M, small colonies from Vedove Shoal (Liguria), 200 m depth. N, small colonies from Candelieri Shoal (Campania), 130 m depth. Scale bars: A–J, M, 50 cm. K, L, N, 10 cm.

Figure 7. Localization of the patches of Parantipathes larix along the remotely operated vehicle (ROV) tracks. Minimum linear distances among the patches are indicated.

Figure 8. Size-frequency distribution of Parantipathes larix for the two forests of Montecristo.

Figure 9. Frequency distribution of the number of branches in Parantipathes larix from Montecristo.