Egyptian Journal of Aquatic Research (2014) 40, 261–268

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FULL LENGTH ARTICLE Faunistic study of benthic Pennatulacea (, ) from the Northern coast of Egypt

Khaled Mahmoud Abdelsalam *

National Institute of Oceanography and Fisheries, Qayet Bey, El-Anfoushy, Alexandria, Egypt

Received 10 June 2014; revised 25 August 2014; accepted 28 August 2014 Available online 11 October 2014

KEYWORDS Abstract Using a trawling net, samples of order Pennatulacea (Sea pens) were collected from the Sea pens; northern coast of Egypt. The current work aims to establish taxonomical data about this distinctive Pennatulacea; group of that dwell in the Egyptian Mediterranean waters. The current study presents 3 New record; species namely; pusilla (Philippi, 1835), rubra Ellis, 1764, and Pteroeides Northern coast; spinosum (Ellis, 1764). The first one pertains to the family of which belongs to the Egypt suborder Sessiliflorae; while the other two species affiliate to two families ( and Pteroeididae) which belong to the suborder Subselliflorae. The present records are the first from the Egyptian Mediterranean waters. A re-description supplied with full structural illustrations of the recorded species is given. ª 2014 Hosting by Elsevier B.V. on behalf of National Institute of Oceanography and Fisheries.

Introduction They are colonial organisms that have a featherlike appear- ance, and are the only octocorals that are adapted to spend Sea pens, or pennatulaceans, are a highly specialized group of their entire life in soft sediments (Edwards and Moore, anthozoan cnidarians. They are benthic sessile animals that are 2009). Unlike other octocorals they are formed by a single adapted exclusively for living partly imbedded in sand, mud, or large primary polyp, also known as the initial polyp or oozo- abyssal ooze deposits. Sea pens are encountered in all of the oid. The primary polyp is anchored into soft sediment by a world’s seas and at virtually all depths (intertidal to over proximal muscular peduncle. The distal region of the primary 6100 meters). Many deeper water species have nearly cosmo- polyp forms a rachis that contains a few or many secondary or politan distributions in such habitats (Williams, 1992). Several daughter polyps. These polyps arise laterally from the central pennatulacean species were originally called sea pens or sea unbranched rachis as autozooids (the larger feeding polyps) feathers because of their resemblance to quill pens (Williams, and siphonozooids (smaller polyps for water circulation). 1995). Thirty-four genera in fourteen families of living Some species have conspicuous polyp leaves, often strap- pennatulaceans were recognized (Williams, 2011a). shaped wing-like expansions, which can contain numerous autozooids. Some species of Pennatulacea may also have polyps which are intermediate in form known as mesozooids. * Tel.: +20 1001164858. Pennatulacean sclerites are usually smooth three-flanged spin- E-mail address: [email protected] dles, sometimes ovals, or rarely irregularly-shaped plates. Peer review under responsibility of National Institute of Oceanography Internally most pennatulaceans have a central axis composed and Fisheries. http://dx.doi.org/10.1016/j.ejar.2014.08.004 1687-4285 ª 2014 Hosting by Elsevier B.V. on behalf of National Institute of Oceanography and Fisheries. 262 K.M. Abdelsalam primarily of calcium carbonate, which runs partially or entirely (1995). Material of the species studied here is deposited in the along the length of the to support the colony. The axis Museum of Marine Biota (MMBT), National Insti- is circular or quadrangular in cross-section. On the other hand, tute of Oceanography and Fisheries, Alexandria, Egypt. some pennatulaceans do not have such axis (Williams, 2011b). Sea pens feed on organic particles that are suspended in the water column and are carried into the zooids by inflowing Results water currents (Musgrave, 1909). According to available literature, the present work is the The Present study yields three species of sea pens that belong first to study the Pennatulacea (Cnidaria, Octocorallia) in the to three genera, three families and two suborders. Egyptian Mediterranean waters. Detailed descriptions for the recorded species are provided.

Phylum: Cnidaria Materials and methods Class: Subclass: Octocorallia Samples of Pennatulacea (sea pens) were sorted from the trash Order: Pennatulacea Verrill, 1865 crop of fishing trawler that was working during April 2014 at Suborder: Sessiliflorae Ku¨ kenethal, 1915 20–25 m deep between Damietta and El-Manzala (at the East- Family: Veretillidae Herklots, 1858 : Cavernularia Milne Edwards and Haime, 1850 ern Mediterranean Coast of Egypt, Fig. 1). The bottom sedi- Cavernularia pusilla (Philippi, 1835) ment of the area is almost muddy mixed with sandy mud. Suborder: Subselliflorae Ku¨ kenethal, 1915 The bottom water temperature and salinity amounted to Family: Pennatulidae Ehrenberg, 1834 18.7 C and 39.9& respectively. Moreover, some pennatula- Genus: Pennatula Linnaeus, 1758 cean colonies showed association with erect Bryozoa and/or Pennatula rubra Ellis, 1764 hydroids. Specimens were fixed on board in 10% formalin Family: Pteroeididae Ko¨ lliker, 1880 before being transferred to 70% ethanol in the laboratory. Genus: Pteroeides Herklots, 1858 According to Williams (1990), sclerites and axial fragments Pteroeides spinosum (Ellis, 1764) of the Pennatulacea specimens were isolated by dissolving the surrounding tissue in concentrated sodium hypochlorite, with Veretillidae Herklots, 1858 repeated rinsing in water and finally in ethanol. Cleaned scle- Cavernularia Milne Edwards and Haime, 1850 rites were mounted on slides for examination and photography. Cavernularia pusilla (Philippi, 1835) Photography was performed by a Nikon digital camera (model Fig. 2(A–k) D5000) equipped with a special adaptor to attach the micro- scopes (Novex P-20 and/or BEL Bio-1-T). In the present work, the key adopted for generic identification is that of Williams pusillum Philippi, 1835: 277, plate 4, Figs. 6–10. Cavernularia pusilla + C. valenciennesi Herklots, 1858: 26. Stylobelemnon pusillum Ko¨ lliker, 1872: 173. Cavernularia pusilla. Ku¨ kenthal and Broch, 1911: 192, Fig. 25–28; Ku¨ kenthal, 1915: 15, fig. 19; Gili and Page` s, 1987:26, Figs. 1d, 3f–g.

Materials

MMBT (CN-2014-1-1), only a single colony was collected from the area of study (3.4 cm retracted length upon preservation).

Description

Upright clavate colony and pyriform. The apical one third of the colony (rachis) differs from the remainder due to its greater thickness, and presence of polyps. The rest of the colony cor- responds to the stalk (peduncle) which is pointed and slightly curved at its end. Symmetry of rachis is radial. Axis prominent extends throughout the entire length of rachis. It is almost straight in shape with little curvatures, and is circular in cross-section at the center which is tapered distally. The apical area of the colony is covered by siphonozooids with a crown of sclerites at their base. Autozooids that are among siphonozooids are distributed randomly, i.e., not Figure 1 Map showing the sampling area in the Mediterranean arranged in longitudinal rows. Autozooids are completely coast of Egypt. retracted into the rachis. Faunistic study of benthic Pennatulacea (Cnidaria, Octocorallia) 263

Figure 2 Cavernularia pusilla. (A) General aspect showing rachis (ra), and peduncle (pe). (B) Enlarged part of rachis showing retracted autozooid (a), and siphonozooids (s). (C) Enlarged part showing sclerites of surface peduncle. (D) Axis. (E and F) Sclerites of surface peduncle. (G) Sclerites of interior peduncle. (H and I) Sclerites of rachis surface. (J and K) Sclerites of rachis interior.

Sclerites are smooth and not three-flanged. They are spin- collected it from 200 m deep in the middle area of the Catalan dles and rods on the surface peduncle, small ovals in the inte- continental shelf. Vafidis et al. (1994) reported it for the first rior of the peduncle, spindles and rods on the rachis surface time from the Eastern Mediterranean (Aegean Sea) on silty (around siphonozooids), and mostly rods in the rachis interior. or sandy silt bottoms, at 30–80 m deep. According to available The length of the sclerites in the surface peduncle varies and literature, the present record of Cavernularia pusilla is the first can reach up to 210 lm, or be as small as <10 lm in the inte- from the Egyptian Mediterranean waters, which represents an rior peduncle. They also have different lengths in the rachis addition to the biodiversity of the Egyptian fauna. The present surface and interior that may reach up to 350 lm and species is rare (single colony) in the study area, as well as, it 270 lm respectively. appears at shallow depth (20–25 m).

Distribution and habitat Remarks

The present species is Atlanto-Mediterranean (Vafidis et al., Lo´ pez-Gonza´ lez et al. (2000) revised the world species of 1994). It was recorded from Biscay Gulf to Senegal genus Cavernularia. Cavernularia pusilla can be distinguished (Williams, 1989), from Western Mediterranean (Ku¨ kenthal from most other Cavernularia species by its long prominent and Broch, 1911; Thomson, 1929). Gili and Page` s (1987) axis that extends throughout the entire length of rachis. It is 264 K.M. Abdelsalam

Figure 3 Pennatula rubra. (A) Ventral view. (B) Dorsal view showing rachis (ra), and peduncle (pe). (C) Enlarged part of rachis showing mesozooids (m), and siphonozooids (s). (D) Axis. (E) Ventral face of single polyp leaf showing calyx (c) of autozooids, and siphonozooids (s). (F) Single retractile autozooid surrounded by calyx. (G) Sclerites of calyx. (H) Sclerites of surface peduncle. (I) Sclerites of interior peduncle. (J and K) Sclerites of the rachis around siphonozooids and mesozooids.

close to C. clavata, but the shape and length of the rachis sur- C. pusilla is distributed through Iberian Atlantic to Senegal face sclerites can distinguish between them. It is mostly spindle and Mediterranean. with length of <550 lminC. clavata (Lo´ pez-Gonza´ lez et al., 2000). In the present species, the rachis surface sclerites are spindles and rods with shorter length (up to 350 lm). This Pennatulidae Ehrenberg, 1834 resembles the description of Gili and Page` s (1987) for Pennatula Linnaeus, 1758 C. pusilla in the Western Mediterranean. On the other hand, Pennatula rubra Ellis, 1764 C. clavata is confined to Indonesia and Taiwan while Fig. 3(A–K) Faunistic study of benthic Pennatulacea (Cnidaria, Octocorallia) 265

Pennatula rubra Ellis, 1764: 426, plate 20, figs. 1–5; Gili and Page` s (1987) detailed its wide distribution in the Cat- Ko¨ lliker, 1869:242, plate 8, figs. 71–72; plate 9, figs. 74–75; alan continental shelf to reach between 30 and 100 m deep. Ku¨ kenthal and Broch, 1911: 382, figs. 182–187; Ku¨ kenthal, Vafidis et al. (1994) reported the first record of the species from 1915: 91, figs. 98–99; Gili and Page` s, 1987:33, figs. 1c, 5g–k; the Eastern Mediterranean (Aegean Sea) on silty or sandy silt Lo´ pez-Gonza´ lez et al., 2001:70. bottoms, reached 25–40 m deep. The colonies in the present study (twenty-three) appear at shallow depth (20–25 m). Few Materials colonies showed association with erect bryozoan species of genus Amathia. According to available literature, the present MMBT (CN-2014-1-2), twenty-three colonies were collected record of Pennatula rubra is the first from the Egyptian from the area between Damietta and El-Manzala (4–10 cm Mediterranean waters, which represents an addition to the retracted length upon preservation). biodiversity of the Egyptian fauna.

Description Remarks

Colonies are feather-like in appearance. The lower part of the In the present study, the red color of sclerites that gives the colony forms a fleshy stalk and is quite cavernous (peduncle); peduncle and polyp leaves their uniform reddish color, is a it involves a central calcified axis. The upper part of the colony characteristic that differentiates Pennatula rubra from the (rachis) comprises many polyp leaves which are distributed on other two recorded species (Cavernularia pusilla and Pteroeides both sides. Symmetry of rachis is bilateral throughout. The spinosum). That red color however, does not differentiate peduncle and polyp leaves are a uniform reddish color due P. rubra from other red-colored species of genus Pennatula. to the color of the sclerites; however, the ends of polyps are In the current study, the rachis forms about 66% of total col- rather white retracted tentacles. Rachis forms about 66% of ony length. This description disagrees with Gili and Page` s the colony’s length, and has a narrow naked dorsal tract. This (1987) working in the western Mediterranean who indicated tract is widest in the lower one third of the rachis. Axis is colonies with short rachis (about one-third of the total colony almost present throughout the length of the colony. It is qua- length). At the same time, it agrees with Lo´ pez-Gonza´ lez et al. drangular in cross-section at the center and is tapered distally (2001) working in the Guinea Bissau, African Atlantic coast, with circular ends. On the dorsal region of the rachis, there are who mentioned that rachis is 63% of the colony length. This large numbers of siphonozooids and mesozooids intermingled difference may be attributed to variations of the ambient envi- with each other. The latter are always surrounded by a pali- ronmental conditions (e.g., water temperature) prevailing at sade of sclerites. One or two mesozooids are also confined to each site. More investigations and samples from different the basal dorsal region of the polyp leaf. On the ventral face geographical areas are needed to declare this variation. and near the insertion of each polyp leaf, some grouped siphonozooids are located. There are 16–26 pairs of polyp leaves per colony. The auto- Pteroeididae Ko¨lliker, 1880 zooids are arranged in a single row at the base, but not so at Pteroeides Herklots, 1858 the apex. Autozooids are 18–30 per developed polyp leaf. Pteroeides spinosum (Ellis, 1764) Fig. 4(A–I) The colony length is of 4–5 cm, it contains 16–18 pairs of polyp leaves with 18 autozooids. Those that are 6–7 cm contain 20– 22 pairs of polyp leaves with 21–23 autozooids; 8–9 cm contain 22–24 pairs of polyp leaves with 24–25 autozooids. Finally Penna grisea Bohadsch, 1761: 109, plate 9, figs. 1–3; Pallas 9–10 cm contains 24–26 pairs of polyp leaves with 26–30 (1766): 367. autozooids. Pennatula spinosa Ellis, 1764: 434, plate 21, figs. 6–10; Delle Sclerites of calyces are in the apical region, they are usually Chiaje (1828): 9, plate 31. fig. 1. smooth needles with three-flanged ridges at both ends, and Pteroeides griseum. Ku¨ kenthal and Broch, 1911: 400; they reach up to 1.4 mm long. However, they are spindle like Ku¨ kenthal, 1915: 98, figs. 104–107. or oval on the surface peduncle, and may reach up to Pteroeides spinosum. Herklots, 1858: 21, plate 3, fig. 1; 170 lm long. On the other hand, sclerites of the interior Gray, 1860: 23; Gili and Page` s, 1987:30, figs. 1g, 5a–f. peduncle are small, oval-shaped, and may reach up to 23 lm. Those located on the rachis around the siphonozooids and Materials mesozooids are almost rods or spindles and reach up to 360 lm long. MMBT (CN-2014-1-3), three colonies were collected from the area between Damietta and El-Manzala (8.4–11.2 cm retracted Distribution and habitat length upon preservation).

Pennatula rubra is Atlanto-Mediterranean. In the Atlantic, the Description British Channel (Gray, 1860), Atlantic coast of Europe (Ku¨ kenthal, 1915), coast of Portugal (Gray, 1870), Guinea, Colonies appear to be stout and feather-like. They are typically Sierra Leone and Ivory Coast (Tixier-Durivault, 1963), and fleshy brown, dark gray to pink in color. They consist of fleshy African Atlantic coast at depth range reached 50–109 m basal area (peduncle) and apical (rachis), in which the grouped (Lo´ pez-Gonza´ lez et al., 2001). In Western Mediterranean polyps are located in highly developed side sheets together. (Thomson, 1929; Berenguier, 1954; Gili and Page` s, 1987). Symmetry of rachis is bilateral throughout. Axis is present 266 K.M. Abdelsalam

Figure 4 Pteroeides spinosum. (A) Ventral view. (B) Dorsal view. (C) Single polyp leaf (lower surface) showing rays (r) of needle-like sclerites, autozooids (a), and proximal zone of siphonozooids (s). (D) Axis. (E) Sclerites of surface peduncle. (F) Sclerites of interior peduncle. (G) Needles of polyp leaf. (H) Sclerites of rachis. (I) Terminal tip of ray needle showing the fine tuberculation. Faunistic study of benthic Pennatulacea (Cnidaria, Octocorallia) 267 throughout the length of the colony. It is circular in cross-sec- According to Vafidis et al. (1994), ten species of order tion at the center and is tapered distally with circular ends. Pennatulacea have been recorded in the Mediterranean Sea. There are 19–21 pairs of polyp leaves per colony, being 19 These are Veretillum cynomorium (Pallas, 1766); Cavernularia pairs in the colony length of <8.5 cm, with more number of pusilla (Philippi, 1835); Kophobelemnon stelliferum (Mu¨ ller, polyp leaves (20–21) in larger colony sizes. Polyp leaves are 1776); quadrangularis (Pallas, 1766); Virgularia well-developed and rigid due to the presence of one to many mirabilis (Linnaeus, 1758); Pennatula aculeata Danielssen, supporting rays composed of long needle-like sclerites. Antho- 1860; Pennatula phosphorea Linnaeus, 1758; Pennatula rubra codiae of autozooids are retractile into the fleshy distal portion Ellis, 1764; Pteroeides griseum (Linnaeus, 1767); and of the polyp leaves. Siphonozooids are minute numerous and Crassophyllum thessalonicae Vafidis and Koukouras, 1991.It crowded in a conspicuous proximal zone of each polyp leaf, is to be noted that eight of them were recorded at both Catalan which is at the leaf’s lower surface. and French coasts; seven at the Aegean Sea and Western Ital- Sclerites are smooth, not three-flanged. They are needle- ian coast; six at the Adriatic Sea; five at Tunisian and Algerian shaped in the polyp leaves, spindles or rods in surface pedun- coasts, Ionian Basin, and Marmara Sea; three at Alboran Sea; cle, oval-shaped in interior peduncle, and mostly rods in the and only one species at both Levantine Basin and Black Sea rachis. The length of needles in the leaves varies and may reach (Vafidis et al., 1994). up to 8 mm. The ends of some needles may contain fine tuber- It is also worth mentioning that in the Levantine Basin, culation. The lengths of the sclerites in the surface and interior only Funiculina quadrangularis was reported from its NW part peduncle also vary, and may reach up to 200 lm and 24 lm, (between Rhodes Island and Megisti Islet) by Pe´ re´ s and Picard respectively. In the rachis, they have different length and (1958). On the other hand, many species of octocoral fauna may reach up to 240 lm. including Pennatulacea were recorded from the Eastern Med- iterranean – east of 21 longitude (Vafidis et al., 1994). Thus, Distribution and habitat the current record of these three species may be an addition to that recorded in the Levantine basin. The species is distributed throughout the Mediterranean, and It is well known that Levantine basin in the overall is the is found on muddy or sandy substrates in shallow and deep most oligotrophic area of the Mediterranean, hence making waters (Musgrave, 1909). The range of depth is from 30 to it an extremely stressed marine environment with a 30% 250 m (Campbell, 1982). On the other hand, other authors impoverishment in the general diversity of its biota (Por and provided deeper depths ranging between 200 and 700 m Dimentman, 1989). However, the report of only one Pennatul- (Ku¨ kenthal, 1915 in Atlantic coast of Europe; Rossi, 1958 in acea species from this basin should not be attributed exclu- Ligurian Sea, Italy). Gili and Page` s (1987) in the Western sively to the general impoverishment; it may also be due to Mediterranean reported that the colonies are quite common the poor sampling efforts in the basin. Nevertheless, more sam- in coastal terrigenous nature or sand, and that the maximum pling efforts in deeper waters along the Egyptian Mediterra- density was observed at depth of 100 m in mixed funds of sand nean coast must be carried out to explore the taxa prevailing and mud. According to available literature, the present record in these localities. of Pteroeides spinosum is the first from the Egyptian Mediter- ranean waters, which represents an addition to the biodiversity Acknowledgements of the Egyptian fauna. The colonies studied here (only three) appear at shallow depth (20–25 m). The author would like to thank Dr. Pablo J. Lpez-Gonza´ lez, Laboratory of Marine Biology, University of Sevilla, Spain Remarks for checking and confirming the identification.

Pteroeides spinosum can be distinguished by the long, sharp References supporting rays located at the end of each polyp leaf which are composed of long needle-like sclerites. In the Western Berenguier, A., 1954. Contribution a` l’e´ tude des Octocoralliaires de Mediterranean, Gili and Page` s (1987) indicated that the long Me´ diterrane´ e occidentale. Recueil des travaux de la Station marine Rays may measure over a centimeter in length. Meanwhile, d’Endoume 12, 53–96. in the present materials the length of rays varies and may reach Bohadsch, J.B., 1761. De quibusdam animalibus marinis, eorumque proprietabibus, orbi litterario vel nondum vel minus notis, liber up to 8 mm. This difference may be attributed to variation of cum nonnullis tabulis aeri incisis, ab auctore super vivis animalibus the colony sizes in the two studied areas and/or variation in the delineatis. Dresdae: apud GC Walther. (Work suppressed by ICZN supply of nutrient salts in the Levantine basin (area of the for nomenclatural purposes). present study). Since the Levantine Basin has the least concen- Campbell, A.C., 1982. The Hamlyn guide to the flora and fauna of the tration of nutrient salts, making it the most oligotrophic area Mediterranean sea. Hamlyn Publishing Group Limited, London. of the Mediterranean Sea (Por and Dimentman, 1989). Danielssen, D.C., 1860. Beskrivelse over en ny Art Virgularia. Forhandl. Videnskags-Selsk, Christiania, 1859, p. 251. Discussion Delle Chiaje, S., 1828. Memorie sulla storia e notomia degli animali senza vertebre del regno di Napoli. Stamperia Della Societa’ Tipografica, p. 232. The present work is the first record of Pennatulacea (sea pens) in Edwards, D.C.B., Moore, C.G., 2009. Reproduction in the sea pen the Egyptian Mediterranean waters, and thus it is an addition to Funiculina quadrangularis (Anthozoa: Pennatulacea) from the west the biodiversity of the Egyptian fauna. Three species were coast of Scotland. Estuar. Coast. Shelf Sci. 82, 161–168. recorded namely: Cavernularia pusilla (Philippi, 1835); Pennatu- Ehrenberg, C.G., 1834. Beitra¨ ge zur physiologischen Kenntniss der la rubra Ellis, 1764; and Pteroeides spinosum (Ellis, 1764). Corallenthiere im allgemeinen, und besonders des rothen Meeres, 268 K.M. Abdelsalam

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