Summary We investigated the seasonal maturity development of cod in four areas of the Baltic Sea. Two different spawning peaks were identified and found to be consistent over the period 1992–2005. In the Kiel Bight and Mecklenburg Bight (ICES SD 22) a spawning peak was observed from March to April (spring spawning). In the areas of the Arkona Sea (ICES SD 24) and Bornholm Sea (ICES SD 25) the spawning peak occurred during summer. In the Bornholm Sea, the main spawning activities began in June and ended in September, with a spawning peak in June–August (summer spawning). In the Arkona Sea, which is a transition area between the Mecklenburg Bight and the central Baltic Sea, spawning began in March and lasted until July, with a spawning peak in June–July (summer spawning). Seasonal maturity development and proportions of spawning cod in June in the Arkona Sea were similar to that of the Bornholm Sea. In addition, the proportion of spawning cod in the Arkona Sea was positively correlated with the size of the spawning stock in the Bornholm Sea. Our results provide evidence of a spatial expansion of spawning activities of the summer spawning stock from the eastern Baltic Sea into the Arkona Sea. Therefore, the Arkona Sea should be considered as one of the spawning habitats of the summer spawning stock of Baltic cod.
Austrobdella coliumicus n. sp. is described from Coliumo Bay, Chile. It is characterized by a continuous, external coelomic canal (= marginal lacuna), 5 pairs of testisacs, accessory gland cells, a body not distinctly divided into trachelosome and urosome, 2 pairs of dorsal ocelli on the trachelosome, dorsal and ventral segmental ocelli present on the urosome, green overall pigmentation with transverse brown bands, and the absence of conducting tissue. Austrobdella coliumicus is distinguished from other species of Austrobdella by the presence of 2 pairs of ocelli on the trachelosome and a more cylindrical body. It is unusual that this leech was collected from inside the mantle cavity of the razor clam, Ensis macha. Austrobdella losmoliniensis n. sp. is described from the electric ray, Discopyge tschudii, collected at Los Molinos, Chile. It is characterized by a continuous, external coelomic canal; 5 pairs of testisacs; accessory gland cells; a body distinctly divided into trachelosome and urosome; 1 pair of eyes on the oral sucker; overall black pigmentation with unpigmented areas; and the absence of conducting tissue. Austrobdella losmoliniensis can be distinguished from other species of Austrobdella by the combination of 1 pair of eyes on the oral sucker and black pigmentation.
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