The swordfish, Xiphias gladius Linnaeus, 1758, is a fish that sporadically enters the Baltic Sea. The present paper describes the identification of a very rarely recorded and poorly studied copepod of the family Philichthyidae – Philichthys xiphiae Steenstrup, 1862 – in a dead swordfish found on a sea beach in Dźwirzyno (Poland) in 2016. Philichthyidae are parasites inhabiting the sensory canals in the lateral line and skull bones of marine fish. In the present case, two P. xiphiae females were found, which constitutes the first record of the species in the Baltic area.

中文翻译：

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（桡足类；Philichthyidae）——一种有趣的从波罗的海收集的箭鱼头盖骨寄生虫

剑鱼，Xiphiasgladius Linnaeus，1758 年，是一种偶尔进入波罗的海的鱼。本论文描述了在 2016 年在 Dźwirzyno（波兰）的海滩上发现的一条死旗鱼中鉴定出一种极少记录且研究甚少的 Philichthyidae 科桡足类动物——Philichthys xiphiae Steenstrup，1862 年。Philichthyidae 是栖息在感觉管中的寄生虫在海鱼的侧线和颅骨中。在本案中，发现了两只 P. xiphiae 雌性，这构成了波罗的海地区该物种的第一个记录。