Bioacoustics of Parabrachiella supplicans

Parabrachiella genypteri was first described as Brachiella genypteri from the branchial cavity of G. capensis off Fort Rock Point, Namibia and transferred to Neobrachiella (Castro & Baeza 1987) and later to Parabrachiella (Piasecki et al . 2010) . This species bears close resemblance to P. supplicans , described from the same host off Table Bay. However, despite the incomplete information on the structure and armature of the appendages, P. genypteri was accepted as a valid species (Castro & Baeza 1987; Piasecki et al . 2010). A comparison of the description and illustrations of P. genypteri with the current description indicates that P. supplicans and P. genypteri are conspecific and should therefore be synonymized. The existing groupings of these species, based on the number of posterior processes, is impractical as there are contradicting reports for some specific Parabrachiella species possessing different numbers of posterior processes while most species have reported morphological variations (Kabata 1979; Knoff et al . 1994). This is evident in P. insidiosa (Heller) , reported to have one pair of posterior processes by Kabata (1970) and two pairs of posterior processes by Kabata (1979) and Barnard (1955a) while P. b e r a has four pairs of posterior processes in Japan (Yamaguti 1939) and one pair of posterior processes in Korea (Moon 2014). The fused or unfused appearance of the arms of the maxillae is also variable with P. supplicans the only species reported herein to show both conditions. ( Figs 1 G, H). According to Piasecki et al . (2010) there are currently 67 valid species in the genus Parabrachiella . However, P. appendiculata (Krøyer) ; P. malabarica (Pillai, Prabha & Balaraman) ; P. pillaii (Kabata & Tareen) ; P. ramosa (Richiardi) ; P. trichiuri (Gnanamuthu) and P. upenaei (Pillai) were omitted while P. elegans (Richiardi) was included. Parabrachiella elegans was however previously assigned to a new genus Eobrachiella (Ho & Do 1984) due to the morphology and armature of the male which seems to be intermediate between Brachiella and Neobrachiella males (Ho & Do 1984), while P. seriolae was synonymized with E. elegans (Ho & Do 1984). Parabrachiella indica (Tripathi) , P . lutiani (Pillai) and P . pillaii (Kabata & Tareen) are three names referring to the same species collected from Lutianus sp. from India and Sparidentex hasta (Valenciennes) in Kuwait (Pillai 1968; Kabata & Tareen 1987). Similarly, Parabrachiella upenaei (Pillai) and P. malabarica (Pillai, Prabha & Balaraman) were transferred to Neobrachiella (Kabata 1979; Castro & Baeza 1987) and thus seem to be valid species of Parabrachiella with no reason to be excluded from the list. Boxshall & Walter (2015) list both P . trichiuri (Yamaguti) and P . trichiuri (Gnanamuthu) as valid species. Ho & Do (1984) examined both P . trichiuri (Yamaguti) collected off Japan and P . trichiuri (Gnanamuthu) collected off India and concluded that they are the same species with small geographical variation. Therefore P . trichiuri (Yamaguti) is the valid species (Ho & Do 1984). Parabrachiella supplicans and P. genypteri as well as P. exilis and P. mugilis are herein synonymized, while P . ramosa (Richiardi) and P. appendiculata (Kroyer) await verification. Therefore the revised total number of valid Parabrachiella species, excluding P. ramosa and P. appendiculata , is 61, namely P. albida (Rangnekar) ; P. amphipacifica (Ho) ; P. anisotremi (Castro & Baeza) ; P. bispinosa (Nordmann) ; P. brevicapita (Kabata) ; P. chavesi (Van Beneden) ; P. chevreuxii (Van Beneden) ; P. chloropthalmi (Kabata) ; P. cirrata (Heegaard) ; P. cirrocauda (Heegaard) ; P. dispar (Castro & Baeza) ; P. exigua (Brian) ; P. exilis ; P. gulosa (Wilson) ; P. gymnofimbriata (Kabata) ; P. hoplognathi (Yamaguti) ; P. incurva Shiino ; P. indica ; P. insidiosa ; P. intermedia (Bere) ; P. kabatai (Luque & Farfan) ; P. merluccii (Bassett-Smith) ; P. microdigitata (Kabata) ; P. m i r i f i c a (Kabata); P. mitrata (Wilson) ; P. multifrimbriata (Bassett-Smith) ; P. nitida (Wilson) ; P. paralicthyos (Castro & Baeza) ; P. regia (Lewis) ; P. robusta (Wilson) ; P. rostrata (Krøyer) ; P. sciaenae (Brian) ; P. septicauda (Shiino) ; P. sihama Song & Chen; P. spinicephala Ringuelet ; P. stellifera (Heegaard) ; P. anserina (Wilson) ; P. auriculata (Castro & Baeza) ; P. bera (Yamaguti) ; P. brevibrachiata (Kabata) ; P. fasciata (Castro & Baeza) ; P. gracilis (Wilson) ; P. hoi (Piasecki) ; P. hostilis (Heller) ; P. hugu (Yamaguti) ; P. jarai Piasecki, Mlynarczyk & Hayward ; P. johnii (Yamaguti) ; P. lata (Song & Chen); P. malabarica ; P. oralis (Castro & Baeza); P. otolithi (Pillai) ; P. pinguis (Wilson) ; P. robusta (Wilson) ; P. rotunda (Pearse) ; P. superba (Leigh-Sharpe) ; P. trichiuri ; P. triglae (Claus) ; P. yongxingensis (Song & Chen); P. annulata (Markewitsch) ; P. menticirrhi (Luque & Farfan) and P. richiardi (Ben Hassine & Raibaut) .