Caligus schlegeli Ho & Lin 2003

Caligus cf. schlegeli Ho & Lin, 2003 (Figs 19A – 20F) Hosts: Cheimerius nufar (Valenciennes); Chrysoblephus puniceus (Gilchrist & Thompson) (Sparidae: Acanthuriformes) Locality: Off east coast South Africa (Indian Ocean) Material examined: 3♀ + 1♂ Material collected: 6♀ + 1♂ from C. nufar; and 2♀ from C. puniceus Voucher material: 2♀ (SAMC-A099207) from C. puniceus deposited in the Iziko South African Museum, Cape Town, South Africa. Adult female (Fig. 19A) cephalothorax slightly longer (about 1.04 times) than genital complex and abdomen combined; genital complex slightly wider than long (about 1.06 times wider than long), longer (about 1.6 times) than abdomen; abdomen shorter, 2-segmented, first segment about twice length of second; antenna (a2) with small, blunt proximal process (arrowed) with marginal membrane (Fig. 19B), claw sharply bent (Figs 19B, C); post-antennal process (pap) sharply bent (Fig. 19C); small rounded process (arrowed) between bases of antenna and post-antennal process (Fig. 19C); maxillule with blunt thump-like dentiform posterior process (arrowed) (Fig. 19D); sternal furca tines divergent, tips slightly incurved, with marginal membrane, small tubercles (arrowed) lateral to sternal furca box (Fig. 19E) (cf. Fig. 121F in Ho & Lin (2004)); leg 1 first exopodal segment broad with convex posterior margin ornamented with spinules (arrowed) (Fig. 19F), terminal seta 4 (4) distinctly longer than terminal spines (ts), but shorter than segment (Fig. 19F), last exopodal segment vestige of posterior margin setae a small spinule (arrowed) (Fig. 19G), terminal spines 1–3 with accessory processes (arrowed) (Fig. 20A); leg 2 exopodal segments 1 and 2 with long distolateral spines (arrowed) lying obliquely across segments, last segment with small, outer spine (os) crossing in front of adjacent longer spine (Fig. 20B); leg 2 second endopodal segment outer margin with denticles (arrowed) (Fig. 20C); leg 3 first exopodal segment distolateral spine (ds) mostly straight, shorter than second segment (Fig. 20D); leg 4 3-segmented with I, IV spines respectively (Fig. 20E), distolateral spine (dls) on first segment reaching about half length of lateral spine (I) on compound segment, lateral spine (I) on compound segment short, barely reaching base of terminal outer spine (II), first two outer terminal spines (II and III) slightly increasing in length from outer to inner, inner terminal spine (IV) slightly more than half length of outer terminal spines (II and III) (Fig. 20E) (cf. Ho & Lin 2004; Boxshall 2018). Remarks: The total body length of the current specimens is about 3.5 mm which is similar to previous reports (Ho & Lin 2004; Boxshall 2018). However, morphological differences were observed in the genital complex of the current specimens that is slightly wider than long whereas it was previously reported to be longer than wide (about 1.2 times) (Ho & Lin 2004; Boxshall 2018). The abdomen is more distinctly 2-segmented with clear lateral indents (arrowed) in the current specimens (see Fig. 20F). Leg 1 last exopodal segment terminal spines 1–3 all with accessory processes (see Fig. 20A) rather than only spines 1 and 2 (Ho & Lin 2004; Boxshall 2018). Leg 2 last exopodal segment small distolateral seta crossing in front of adjacent spine (Fig. 20B) similar to that illustrated by Ho & Lin (2004) in figure 122C but different from Boxshall (2018) in figure 53D. Leg 4 (see Fig. 20E) with outer spines on last segment shorter than those of both previous illustrations (cf. Fig. 122E in Ho & Lin (2004) and Fig. 53F in Boxshall (2018)). Even with mentioned differences the examined specimens still conform mostly to the characteristics of C. schlegeli as previously described (Ho & Lin 2004; Boxshall 2018) rather than any of the other species in the productus -group with only a vestige of a seta on the posterior margin of leg 1 last exopodal segment (i.e. C. arricolus Wilson; C. enormis Wilson; C. haemulonis Krøyer and C. turbidus Boxshall) instead of three pinnate setae. Caligus schlegeli has been reported from a variety of host species (Ho & Lin 2004; Boxshall 2018), but this is the first report from C. nufar and C. puniceus off the east coast of South Africa. Therefore, this report of C. cf. schlegeli from C. nufar and C. puniceus from South Africa are both new host and locality records.