Aethon morelandi Hewitt 1968
Creators: name: Boxshall, Geoff A.
name: Bernot, James P.
name: Barton, Diane P.
name: Diggles, Ben K.
name: Q-Y, Russell
name: Atkinson-Coyle, Toby
name: Hutson, Kate S.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Maxillopoda
Siphonostomatoida
Lernanthropidae
Aethon
Aethon morelandi

description: Aethon morelandi Hewitt, 1968
(Fig. 5)
Material examined: 20♀♀, 18♂♂ on Nemadactylus macropterus (Forster, 1801), Coffs Harbour, New South Wales, collected by K. Rohde; NHMUK Reg. No. 1982.86. 1♂ from N. macropterus, Coffs Harbour, New South Wales, 15 November 1981; collected by K. Rohde; NHMUK Reg. No. 1992.163–172. 1♀ from “Morwong” (Chei- lodactylidae), Port Macquarie, New South Wales, 01 September 1980; collected by K. Rohde; NHMUK Reg. No. 1992.153–162. 1♀ from Nemadactylus valenciennesi (Whitley, 1937), Port MacDonnell, South Australia, collected by K.S. Hutson, 09 May 2007, SAMA Reg. No. C 6891.
Differential diagnosis: Cephalothorax markedly wider than long, with distinct dorsal cephalothoracic shield; lateral margins with 2 pairs of lateral processes (Fig. 5 A–C), posterior pair much longer than anterior pair; tips of both pairs with papillate surface ornamentation. Trunk distinctly wider than cephalothorax: anterior part with 2 well-defined dorsal tergites derived from second and third pedigerous somites, posterolateral margins extended into pointed posterolateral processes; posterior part of trunk (fourth pedigerous somite) covered by dorsal trunk plate. Plate just longer than wide, with evenly but weakly convex lateral margins; posterior margin with deep median indentation and shallower lateral indentations (Fig. 5A). Looped egg strings entirely concealed beneath dorsal trunk plate in dorsal view. Urosome comprising fifth pedigerous somite, genital complex and 1-segmented abdomen all fused. Anal somite bearing paired caudal rami, each 1.3 times longer than wide, with bluntly rounded apex. Leg 2 with endopod fused to protopod forming curved process bearing reduced exopod as small protuberance on outer side of process. Leg 3 large, comprising 2 lamellate lobes; outer lobe (exopod) rigid and highly sclerotised, orien- tated vertically and running length of trunk plate, forming side wall of cavity containing loosely coiled egg strings; external surface of outer lobe with papillate surface ornamentation: inner lobe (endopodal) orientated horizontally and extending posteriorly about to end of trunk plate; inner lobe fleshy, lacking surface ornamentation. Leg 4 bilobate; both lobes lamellate with rounded tip, inner lobe shorter than outer. Mean body length of ♀ 4.33 mm and of ♂ 1.66 mm (length data from Boxshall, 1989).
Distribution: This species was originally described from New Zealand waters on the latrid Latridopsis ciliaris (Forster, 1801) (Hewitt, 1968). The first record from Australia was from Coffs Harbour (New South Wales) on the cheilodactylid Nemadactylus macropterus (Boxshall, 1989). A subsequent record of this species from N. valenciennesi caught in South Australia is reported here.
Remarks: Aethon morelandi was established on the basis of three females found on the gills of Latridopsis ciliaris caught at Ngaraunga near Wellington, New Zealand (Hewitt, 1968). The male was subsequently described from the same host caught at Portobello, east of Dunedin, New Zealand (Rohde et al., 1980). Both sexes were redescribed in detail by Boxshall (1989), based on material from Coffs Harbour.
description: Published as part of Boxshall, Geoff A., Bernot, James P., Barton, Diane P., Diggles, Ben K., Q-Y, Russell, Atkinson-Coyle, Toby & Hutson, Kate S., 2020, Parasitic copepods of the family Lernanthropidae Kabata, 1979 (Copepoda: Siphonostomatoida) from Australian fishes, with descriptions of seven new species, pp. 1-103 in Zootaxa 4736 (1) on pages 13-14, DOI: 10.11646/zootaxa.4736.1.1, http://zenodo.org/record/3669745