Morphological Redescription of the Rare Caprellid Protogeton incertus (Crustacea: Amphipoda: Caprellidae) from Korea

Abstract

The genus Protogeton Mayer, 1903 is one of the 89 genera belonging to the family Caprellidae (WoRMS Editorial Board, 2016). Among them, the genus Protogeton is charac terized by having (1) flagellum with 3-5 articles in antenna 2; (2) mandible lacking molar, with uni-or biarticulate palp;(3) pereonites 3-4 with gills; (4) pereopods 3-5 well developed, consisting of 6articulates; and (5) lacking appendages on the abdomen (Arimoto, 1976). This genus is a taxon with only two species; P. incertus Mayer, 1903 andP. inflatus Mayer, 1903, which are distributed in the northern Pacific and Indian Ocean regions. Protogeton incertus is discernible from P. inflatus by the biarticulate mandibular palp and swollen carpus and propodus on pereopod 3 (GuerraGarcía, 2004). The original description of P. incertus by Mayer (1903) was incomplete, with only one illustration for mandibular palp. Later, Arimoto (1980) and GuerraGarcía (2004) redescribed this species; however, the redescriptions were also brief and not supported by detailed illustrations. There fore, this time, we provide full description of Korean Proto geton incertus including illustrations for mouthparts and appendages and a description of the immature male, especial ly with the dimorphic character of pereopod 3. Specimens were collected by light trap from the shallow and sublittoral waters in Korea (Fig.

First record of the genus Pseudaeginella Mayer, 1890 (Crustacea, Amphipoda, Caprellidae) with a new species from Korean waters

“…In this article, we provide a full description of the new species of Pseudaeginella from Korean waters, with a brief description of the female, focusing on sexually dimorphic characters. So far, 10 genera of caprellids have been recorded in Korean waters ( Kim and Lee 1975 ; Lee 1988 ; Lee and Hong 2009 , 2010 ; Hong et al 2015 ; Heo et al 2016 ; Shin et al 2021 ). Pseudaeginella is newly recorded for the Korean caprellid fauna and is the first record of the genus from the Northwest Pacific region, including Korea.…”