A new hemiarthrine bopyrid, <i>Izuohshimaphryxus hoshinoi</i> (Crustacea: Isopoda) from Izu-Ohshima Island, Sagami Sea, Pacific coast of central Japan

Abstract

Abstract. Izuohshimaphryxus hoshinoi, a new genus and species of hemiarthrine bopyrid, is described on the basis of a single female specimen from the coastal waters of Izu-Ohshima Island, Sagami Sea, Pacific coast of central Japan. This bopyrid infests an anthozoan-associated shrimp, Ancylomenes speciosus (Okuno, 2004), attaching to the dorsal surface of the pleon. This new genus is most similar to Filophryxus Bruce, 1972 but is distinguished by a) the presence of pereopods on the concave side, b) number of lateral plates of the pleon, and c) absence of a pleotelson. This is the third identified species known to attach to the dorsal surface of the pleon of a caridean shrimp host.

A new hemiarthrine bopyrid, <i>Quadripediphryxus mayuzumii</i> gen. et sp. nov. (Isopoda: Epicaridea: Bopyridae), infesting the abdomen of <i>Synalpheus streptodactylus</i> Coutière, 1905 (Decapoda: Caridea: Alpheidae)

“…The numbers of pereopods (seven and four) on the concave and convex sides of the body in the female of the new genus support a close relationship with the genera Hemiphryxus Bruce, 1978, Eriphrixus Markham, 1990, and Micropodiphryxus Boyko, 2012, each of which is known only from its type species; Hemiphryxus malindiae (Bruce, 1974) from Coralliocaris superba (Dana, 1852) (Palaemonidae), Eriphrixus obesus Markham, 1990 from Periclimenes vaubani Bruce, 1990 (Palaemonidae), and Micropodiphryxus richardsonae (Chopra, 1930) from Philocheras lowisi (Kemp, 1916) (Crangonidae) (Chopra, 1930;Bruce, 1974Bruce, , 1978Markham, 1990;Boyko, 2012). These characters are not found in any other genera of Hemiarthrinae (Miura, 2014;An et al, 2015;Saito, 2015). However, the female of the new genus can be readily distinguished from those of the above-mentioned genera by the presence of a tiny triangular pleotelson (vs. bifid in Micropodiphryxus, a globose knob in Eriphrixus, and absent in Hemiphryxus) and uropods (vs. absent in those genera).…”

“…The subfamily Hemiarthrinae Markham, 1972 contains modified bopyrid isopods that mostly occur on the ventral or dorsal surfaces of the abdomens of marine caridean shrimps (Markham, 1972). Sixty species in 28 genera have been recorded worldwide (Boyko et al, 2008 onwards), with 11 described and four unidentified species known from Japan, attached to the abdomens of caridean shrimps belonging to five families (Alpheidae, Hippolytidae, Palaemonidae, Pandalidae, and Rhynchocinetidae) (Saito, 2015). A specimen of snapping shrimp, Synalpheus streptodactylus Coutière, 1905 (Decapoda: Caridea), was collected by an amateur aquarist, bearing one female hemiar-thrine bopyrid accompanied by one dwarf male on the ventral pleon of the shrimp and brought to the present author.…”

First record of <i>Pleurerythrops</i> <i>secundus</i> (Crustacea, Mysida) in association with benthic hydroids (Cnidaria, Hydrozoa) in shallow waters of Izu-Ohshima, Pacific coast of central Japan

“…Some species live in association with benthic invertebrates such as sponges, sea anemones, corals, and hermit crabs, although most are free-living and inhabit the near-bottom layer (Mauchline, 1980;Fukuoka, 2004). The second author, OH, has made several new records of small marine animals by underwater observation during scuba diving (Uyeno & Nagasawa, 2010, 2012Saito & Hoshino, 2011Ota et al, 2012;Saito, 2012Saito, , 2015Yamada & Hoshino, 2014;Saito et al, 2014;Uyeno, 2015;Hoshino & Saito, 2016;Shimomura, 2016Shimomura, , 2017Shimomura & Hoshino, 2017;Okuno, 2017). Recently, he found mysids attached to several species of hydroids (Cnidaria).…”