Anales de Biología 27: 85-100, 2005 Significance of rare reproduction occurrences among recent nodosariids and other benthic foraminifera Engin Meriç1, Muhittin Görmüs¸2, Jan Kresten Nielsen3, Niyazi Avs¸ar4 & Ismail Ünsal5 1 Istanbul University, Marine Sciences and Management Inst. 34470 Vefa-Istanbul, Turkey. 2 Süleyman Demirel University, Engineering and Architecture Faculty, Geology Department 32260 Çünür-Isparta, Turkey. 3 INCREMENTS Research Group, Institute of Geology and Palaeontology, J.W. Goethe University Frankfurt am Main, Senckenberganlage 32-34, D-60325 Frankfurt a.M., Germany. 4 Çukurova University, Engineering and Architecture Faculty, Geology Department 01330 Balcalı-Adana, Turkey. 5 Istanbul University, Science Faculty, Biology Department 34459 Vezneciler-Istanbul, Turkey. Abstract Correspondence Rare morphologies of nodosariids and other benthic foraminifera J.K. Nielsen reported from various locations and depths in the seas present data E-mail: [email protected] valuable in interpreting both past and recent environmental conditions. Tel: +49 (0)69 798 22974 A few abnormal nodosariids and other benthic foraminifera have been Fax: +49 (0)69 798 22958 found at the Saros Gulf, near the island of Bozcaada, at the Edremit Received: 1 September 2005 Gulf (northern Aegean Sea) and Gökova Gulf (southern Aegean Sea) Accepted: 7 November 2005 off the coast of W Turkey. The unusual morphology of these foraminifera, “improbable” and rare, is mysterious clues to the natural survival of such organisms. Environmental conditions such as temperature and trace elements may play an important role in stimulating such unusual test occurrences. Warm-water sources in deep-sea environments carry rare trace elements that cause unusual appearances of benthic foraminifera during reproduction. These remarkable and rare specimens found by chance provide data relevant to the reproduction history of nodosariids and other benthic foraminifera. Key words: Abnormal forms, Amphicoryna, Astacolus, Pyramidulina, Adelosina, Peneroplis, Rosalina, Euuvigerina, Turkey. Resumen Significado de la presencia de morfologías raras durante la reproducción en los nodosaridos actuales y otros foraminíferos bentónicos. La presencia de morfologías raras en nodosaridos y otros forami- níferos bentónicos recogidos en distintas zonas y profundidades mari- nas proporcionan datos valiosos para interpretar las condiciones am- bientales pasadas y recientes. Se han encontrados unos pocos ejem- plares anormales a cierta distancia de la costa occidental de Turquía, en el Golfo de Saros, cerca de la isla de Bozcaada, en el Golfo de Edremit (Egeo septentrional) y en el Golfo de Göcova (Egeo meridio- nal). La morfología inusual de esos foraminíferos, rara e “improbable” es una pista enigmática de la supervivencia natural de tales organis- mos. Ciertas condiciones ambientales, como la temperatura, y los elementos traza pueden jugar un papel importante en la estimulación de estos inusuales fenómenos. Las fuentes de aguas cálidas en los medios marinos profundos transportan elementos traza raros que pro- ducen la aparición de apariencias morfológicas inusuales durante la 86 E. Meriç et al. Anales de Biología 27, 2005 reproducción en los foraminíferos bentónicos. Estos llamativos y raros especímenes proporcionan datos relevantes sobre la historia reproduc- tiva de los nodosaridos y otros foraminíferos bentónicos Palabras clave: Formas anormales, Amphicoryna, Astacolocus, Pyramidulina, Adelosina, Peneroplis, Rosalina, Euuvigerina, Turquía. Introduction Let us now summarize the literature on adhesive twin and triplet forms of Holocene foraminifera. Le Although studies of recent foraminiferal reproduction Calvez (1950) described twin forms of Planorbulina described in the literature reflect investigations mediterranensis D’Orbigny as polyvalent individuals. through 95 years, the reproduction of fossil benthic Valuable scientific contributions are coming from and planktonic foraminifera has only been undertaken various localities (Arnal 1955, Rötgerr & Spindler during the past 40 years. Detailed investigations of 1976, Debenay & Pages 1987, Debenay 1990, Sharifi peculiar occurrences, such as twin and triplet forms et al. 1991, Almogi-Labin et al. 1992, Yanko et al. of fossil foraminifera, began as recently as 1950. A 1994, 1998, Meriç 1996, Geslin et al. 1998, Stouff et brief review of the literature is necessary to evaluate al. 1999, Meriç et al. 2001a, b). Adhesive twin fossil and understand the problems. Let us look at the morphology in Turkey has been handled by Meriç reproduction of Holocene foraminifera in respect to (1972, 1976, 1979, 1992b), Inan & Meriç (1995), Inan abnormal occurrences throughout the principal et al. (1996), Meriç & Görmüs¸ (1999, 2000), foraminiferal genera and species focusing on the Matsumaru et al. (2000) and Görmüs¸ & Meriç (2000). Holocene adhesive twin and triplet forms. There is relatively little data on fossil planktonic twins Le Calvez (1953) and Grell (1958) have illustrated and triplets in the literature. Boltovskoy (1982) first the reproduction methods of primitive forms of recent introduced the matter, and Nazik (2002) has recently foraminifera. Other scholars have also investigated dealt with the subject as well. the reproduction and life cycles of Holocene All the literature cited, however, deals with the foraminifera. Examples of recent foraminifera and occurrences of twin and triplet forms among the same researchers responsible are as follows: Peneroplis species. Only a few of those studies illustrate forms pertusus (Forskål), Winter (1907); Elphidium crispum with linear twin-triplet configurations (Loeblich & (Linnaeus), Myers (1938) and Le Calvez (1953); Tappan 1964, 1988, 1994, Cimmerman & Langer Glabratella patelliformis (Brady), Myers (1938) and 1991). Neither has the researchers taken adhesive Grasse (1953); Spirillina vivipara Ehrenberg, Myers twins of different species of one genus, and of (1936); Patellina corrugata Williamson, Myers different genera into account, nor to say, and linear (1935a, b); Rubratella intermedia Grell and Rotalia twins and triplet occurrences of different forms. Thus, heterocaryotica Grell, Myers (1938) and Berthold the main object of this paper is linear abnormal (1971); and Amphistegina gibbosa d’Orbigny, Harney occurrences displaying the adhesion of different et al. (1998). For benthic fossil foraminifera, Cassan genera among nodosariids and other benthic & Sigal (1961) recorded the first data on schizogonic foraminifera. Furthermore, the occurrences may reproduction. The studies of Meriç (1966a, 1970, provide new evidence on the environmental 1973, 1976, 1996) and Meriç et al. (1997) have conditions during their formation. As a result, a more followed. Some of Meriç’s studies (1964, 1966b, precise palaeoenvironmental approach to abnormal 1967, 1971, 1975, 1976) and that of Meriç & Görmüs¸ occurrences is proposed. (1997) introduce a new interpretation of the asexual reproduction of megalospheric individuals. However, Materials and Methods many questions related to features of reproduction still remain unanswered, especially among benthic genera The remarkable specimens previously illustrated from such as Pleurostomella, Anomalina, Cassidulina and various localities (Fig. 1) are most interesting. In Nonion. Furthermore, the reproduction cycles of addition, we introduce more specimens with unusual different genera of the Buliminacea and Nodosariacea linear configurations from the Saros Gulf, Bozcaada superfamilies also remain unknown (Loeblich & and Edremit Gulf in the N Aegean Sea, and Gökova Tappan 1964, 1988). There is still insufficient data Gulf in the S Aegean Sea off W Turkey (Fig. 2). The on these forms. specimens are from samples of surface sediments Anales de Biología 27, 2005 Reproduction and Foraminifera 87 Figure 1. Distribution of volcanos, deep marine trenches (after Stowe 1979) and find spots of abnormal nodasariid and other benthic foraminifera. 1, The Timor Sea (Loeblich & Tappan 1988, 1994); 2, The Tyrrhenian Sea (Cimerman & Langer 1991); 3-4, The Aegean Sea (Saros Gulf and Bozcaada, this work); 5, An anonymous site in the Pacific Ocean (Loeblich & Tappan 1964). Figura 1. Distribución de volcanes, de fosas marinas profundas ( Stowe 1979) y de los puntos de hallazgo de nodasaridos anormales y de los otros foraminiferos bentonicos. 1, Mar de Timor (Loeblich & Tappan 1988, 1994); 2, Mar Tirreno (Cimerman & Langer 1991); 3-4, Mar Egeo (Golfo de Saros y Bozcaadajo); 5, Un lugar en el Océano Pacífico (Loeblich & Tappan 1964). exposed on the sea bottom. After washing and drying A few recent nodosariid foraminifera display the samples, the specimens were picked from the linearly formed twin or triplet individuals such as detrital sediments. Our interpretation of linear twin Amphicoryna sublineata (Brady) (Fig. 3a); and triplet forms of the same and different nodosariid Amphicoryna separans (Brady) (Figs. 3d, f); species is based on these new Turkish specimens as Amphicoryna scalaris (Batsch) (Fig. 3g); and well as the previously known occurrences throughout Amphicoryna separans (Brady) (Fig. 4a). Although the world (Fig. 1). In particular, we seek the cause described in the literature as representing the same for such occurrences. The organisms from Turkey species, no comment is given on their formation. have been examined with the scanning electron Figures 1, 2 and 5 here show the find spots of these microscope of Arçelik Company, Turkey. All new rare specimens as well as their schematic