Redescription of two Pennellids (Copepoda, Siphonostomatoida) from Korea with a key to species of Peniculus von Nordmann, 1832.

Redescriptions of two pennellid copepods, Peniculus minuticaudae Shiino, 1956 and Peniculus truncatus Shiino, 1956, are provided, based on postmetamorphic adult females collected from marine ranched fishes captured at Tongyeong marine living resources research & conservation center, Korea. Peniculus minuticaudae was collected from the soft fin rays of black scraper Thamnaconus modestus. It can be distinguished from the other two closely related congeners Peniculus ostraciontis Yamaguti, 1939 and Peniculus truncatus by having a well developed triangular-shaped abdomen; the abdomen is rudimentary in other two species. This is thefirst report of the occurrence of Peniculus minuticaudae in Korea. Peniculus truncatus was collected from the dorsal fin of Korean rockfish Sebastes schlegelii. It can be distinguished from Peniculus minuticaudae by the combination of a rudimentary abdomen, long neck and setae on leg 1 and from Peniculus ostraciontis by the long neck, slender trunk, and setae on leg 1. It is also shown that Peniculus truncatus captured from the same host in Korea was misidentified as Peniculus ostraciontis and hence, this is thesecond record of the occurrence of Peniculus truncatus in Korea. A key is provided for the 14 nominal species of Peniculus.

Isolation and characterization of bacteria from the copepod Pseudocaligus fugu ectoparasitic on the panther puffer Takifugu pardalis with the emphasis on TTX.

A total of 50 bacterial isolates was obtained from the copepod Pseudocaligus fugu, which is a common parasite, collected from the body surface of the panther puffer Takifugu pardalis. On the basis of colony characteristics, these bacterial isolates were grouped into six types, of which only two (Types-I and -II) showed a high affinity for adhesion to the carapace of the banana shrimp Penaeus merguiensis. These two types of adhesive bacteria were identified through 16S rRNA sequence analysis as Shewanella woodyi (Type-I) and Roseobacter sp. (Type-II). Representative isolates of these two adhesive bacteria were examined for tetrodotoxin (TTX) production by high-performance liquid chromatography (HPLC)-fluorometric system, gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). It was rather unexpectedly revealed that TTX and anhydroTTX were present in the supernatant of culture of the Type-II isolate Roseobacter sp.