Research Article |
Corresponding author: Melih Ertan Çinar ( melih.cinar@ege.edu.tr ) Academic editor: Christopher Glasby
© 2014 Melih Ertan Çinar, Kristian Fauchald, Ertan Dagli.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
ÇINAR M, Fauchald K, Dagli E (2014) Occurrence of Diopatra marocensis (Annelida, Onuphidae) in the eastern Mediterranean. ZooKeys 445: 1-11. https://doi.org/10.3897/zookeys.445.8464
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The present study deals with the presence of Diopatra marocensis in the eastern Mediterranean. This species is small-sized and inhabited muddy bottom near the opening of rivers or lagoons [salinity range: 33−39‰] in the Aegean and Levantine Seas, and reached a maximum density of 90 ind.m-2 in Mersin Bay. This species might be an alien species that was introduced from the East Atlantic (near Gibraltar) to the eastern Mediterranean via ballast water of ships, as it has never been reported from the western Mediterranean Sea.
Polychaeta , Levantine Sea, Aegean Sea, Turkey
The genus Diopatra Audouin & Milne-Edwards, 1833 is represented by 59 species world-wide (
Diopatra neapolitana was previously regarded as a widely distributed species from the Atlanto-Mediterranean to the Indo-Pacific regions (see
During the biodiversity and pollution-monitoring projects performed along the coasts of Turkey between 2005 and 2012, we came across small individuals of a Diopatra species, especially in the eastern part of the Levantine Sea (in Iskenderun and Mersin Bays) that were first identified as Diopatra sp. (
Specimens of Diopatra marocensis were collected at 7 stations in the Levantine Sea (stations K41, 71, G11, 34, D13, D14 and 11) and at 4 stations in the Aegean Sea (stations 3, 15, G40, 37) between 2005 and 2012, using a Van Veen grab (sampling an area of 0.1 m-2) and a dredge (stations D13 and D14) (Figure
Diopatra marocensis:
ESFM−POL/2009−196, 29.04.2009, Mersin Bay, near the opening of Seyhan River [salinity: 34‰], station 34, 36°43'33"N, 34°52'11"E, 9 m, mud; ESFM−POL/2005−1511, 1 September 2005, Kale, K41, near Beymelek Lagoon [salinity: 39‰], 36°14'29"N, 30°01'33"E, 5 m, gravelly sand, 1 specimen; ESFM−POL/2005−107, 10 September 2005, D13, near the opening of Ceyhan River [salinity: 39‰], 36°33'22"N, 35°34'17"E, 10 m, muddy sand, 8 specimens; ESFM−POL/05−295, 10 September 2005, İskenderun Bay, D14, near the opening of Ceyhan River [salinity: 38‰], 36°32'51"N, 35°34'37"E, 25 m, 3 specimens; ESFM−POL/2005−1396, 17 September 2005, Mersin Bay, G11, near the opening of Seyhan River [salinity: 38‰], 36°45'47"N, 34°51'54"E, 5 m, mud, 14 specimens; ESFM−POL/2005−2086, 8 October 2005, Kuşadası [salinity: 39‰], G40, 37°52'00"N, 27°15'27"E, 10 m, sandy mud, 3 specimens; ESFM−POL/2009−34, 4 February 2009, Mersin Bay, station 34, near the opening of Seyhan River [salinity: 38‰], 36°43'33"N, 34°52'11"E, 9 m, mud, 2 specimens; ESFM−POL/2009−300, 29 April 2009, Mersin Bay, station 34, near the opening of Seyhan River [salinity: 34‰], 36°43'33"N, 34°52'11"E, 9 m, mud, 4 specimens; ESFM−POL/2009−281, 20 October 2009, Mersin Bay, station 34, near the opening of Seyhan River [salinity: 38‰], 36°43'33"N, 34°52'11"E, 10 m, mud, 2 specimens; ESFM−POL/2011−48, 23 August 2011, Enez, near the opening of Meriç River [salinity: 33‰], station 3, 40°43'41.5"N, 26°02'03.1"E, 4 m, sandy mud, 1 specimen; ESFM−POL/2011−256, 28 August 2011, near the opening of Bakırçay River [salinity: 39‰], station 15, 38°55'11"N, 26°58'50"E, 4 m, sandy mud, 1 specimen; ESFM−POL/2011−255, 1 September 2011, near the opening of Büyük Menderes River [salinity: 39‰], station 37, 37°32'39"N, 27°10'28"E, 5 m, sandy mud, 2 specimens (juvenile); ESFM−POL/2011−254, 10 September 2011, Mersin Bay, near the opening of Seyhan River, station 71 [salinity: 37‰], 36°47'00"N, 34°38'06"E, 6 m, sandy mud, 1 specimen; ESFM−POL/2012−1, 17 June 2012, Iskenderun Bay, Yumurtalık [salinity: 39‰], station 11, 36°50'27"N, 35°54'32"E, 12 m, mud, 6 specimens.
All specimens incomplete, except for juvenile specimens from stations G40 and 37, and a mature specimen from station 71 (ESFM−POL/2011−254); having 27 mm body length, 1.3 mm body width (chaetiger 5) and 102 chaetigers. Large specimen incomplete, 35 mm long (H+10 = 5 mm), 2.1 mm wide, with 83 chaetigers. Body somewhat semicircular, anterio-ventral side flat in most specimens; a ventral groove in some highly contracted specimens. Anterior end including first 2 chaetigers larger than following chaetigers (Figures
Antennae and palps covering dorsum of prostomium, emerging near posterior part of prostomium. One pair of pyriform, subulate or digitiform frontal lips on anterior part of prostomium; large specimen having an anomaly; with three frontal lips; on left side of prostomium, two lips attached with each other at base present. Upper lips, massive, medially distinctly separated; with a distinct, elongated papilla between lips (no ridge between halves); each lip cushion shaped, with large, bulbous distal papilla (Figure
Peristomium shorter than first chaetiger, narrow on dorsal side, becoming larger laterally; ventral side as long as dorsal side. Peristomial cirri present, emerging anterio-dorsal side of peristomium; digitiform, longer than peristomium, extending to posterior part of prostomium (Figure
Ventral cirri digitiform on chaetigers 1−4, emerging from posterio-ventral side of parapodia (Figure
Upper fascicle of chaetiger 1 with 2 slender limbate chaetae (Figure
Branchiae starting from chaetiger 4 on majority of specimens; four specimens possessing first branchiae on chaetiger 5. Branchiae with more than 10 spiraled whorls of long filaments (15 spiraled whorls on large specimen); decreasing gradually in number of whorls and in size after chaetiger 12 (7 spiraled whorls on chaetiger 15, 3 spiraled whorls on chaetiger 30); having 2 filaments after chaetiger 35, one filament after chaetiger 37, becoming a short papilla between chaetiger 40 and 46, absent posteriorly.
Mandibles partly sclerotinized (proximal parts) with calcareous distal cutting figs, rounded tip with distal indentations. Maxillae distinctly sclerotinized along cutting edges; supporting structures barely sclerotinized. Maxillary formula: Mx I = 1 + 1; Mx II = 8 + 7; Mx III = 7 + 0; Mx IV = 7 + 9; Mx V = 1 + 1.
Pygidium with two pairs of pygidial cirri; ventral pair (0.5 mm) longer than dorsal pair (0.2 mm).
Tube parchment-like, cylindrical, surface covered by debris comprising mud with shell fragments of Abra alba (Wood W., 1802) and Parvicardium exiguum (Gmelin, 1791), and plant debris drifted from rivers.
This species was found near the opening of rivers or lagoons [salinity range: 33−39‰] in the area between 4 and 25 m depth, and attained its highest density at station 34 (90 ind.m-2).
Gut content analysis of digestive tracks of some worms revealed that this species mainly feeds on algae.
One specimen has eggs in its coelomic cavity, measuring 200 µm in diameter on average. This species is known to be a simultaneous hermaphrodite, brooding large eggs (about 600 µm) in the parental tube (
Specimens of Diopatra marocensis collected from stations D14 and 34 were densely infected by a parasite (?Entoprocta). The parasite is attached to the dorsal side, parapodia and branchiae of the worms. One specimen (ESFM−POL/2009−34) with 15 chaetigerous segments (posterior part is missing) had almost 40 parasites.
This species is only known from the East Atlantic (near Gibraltar; Morocco, Spain and Portugal) and the eastern Mediterranean. The presence of this species in the eastern Mediterranean and absence in the western Mediterranean is interesting. There could be two reasonable explanations for its presence in the eastern Mediterranean; 1) this species might have been introduced to the area by ballast water of ships; 2) it might be an Atlanto-Mediterranean species that widely occurs near openings of river mouths in the area, but has been overlooked up to now, or misidentified as a juvenile specimen of the large Mediterranean species D. neapolitana. These explanations can be refuted or proved when more data regarding this species in different basins of the Mediterranean are accumulated. As there is a big gap between the Atlantic and Mediterranean populations of this species, this species can be regarded as a new alien species for the Mediterranean Sea, at least for now.
Diopatra marocensis can be distinguished from other Diopatra species (D. neapolitana, D. marocensis, D. micrura, D. biscayensis and D. cryptornata) reported from the north-eastern coast of the Atlantic Ocean and Mediterranean Sea, in having pectinate chaetae that have oblique combs with 16−18 thin teeth. The original description of D. marocensis differs from the re-description of the species based on the eastern Mediterranean specimens in having different pigmentation in the anterior end (generally pale, but small specimens having palps with irregular brownish specks, and peristomium and anterior chaetigers with mid-dorsal bars on the posterior part of segment) and branchiae with fewer numbers of whorls (max. 8−9 whorls in the original description vs. 15 in the eastern Mediterranean specimens). However, such characters of the eastern Mediterranean specimens were also noted on the Spanish specimens (H. Paxton, pers. comm.).
This work is financially supported by two TUBITAK Projects [Project Numbers: 104Y065 (2005 samples) and SINHA 107G066 (2009 samples)] and an integrated pollution monitoring project (2011 samples) of the Ministry of Environment and Urbanization/General Directorate of Environmental Management (coordinated by Derinsu Underwater Engineering). Authors are indebted to Dr. Hannelore Paxton for her constructive comments on the manuscript.