Caligus chrysophrysi Pillai, 1985

Dippenaar, Susan M. & Sebone, Makwena M., 2025, Caligus (Caligidae: Siphonostomatoida) species off southern Africa with the description of C. pillaii sp. nov., Zootaxa 5686 (2), pp. 151-197 : 179-181

Caligus chrysophrysi Pillai, 1985

( Figs 24A–F )

Hosts: Aetobatus narinari (Euphrasen) ( Aetobatidae : Myliobatiformes ); Aetomylaeus bovinus (Geoffroy Saint- Hilaire) ( Myliobatidae : Myliobatiformes ); Rhinoptera javanica Müller & Henle ( Rhinopteridae : Myliobatiformes ); Rhina ancylostomus Bloch & Schneider ( Rhinidae : Rhinopristiformes ); Rostroraja alba (Lacepède) ( Rajidae :

Rajiformes ); Squatina africana Regan ( Squatinidae : Squatiniformes ); Rhizoprionodon acutus (Rüppell) ( Carcharinidae : Carchariniformes); Carcharias taurus Rafinesque ( Carchariidae : Lamniformes ).

Locality: Off east coast South Africa (Indian Ocean)

Material examined: 5♀ + 5♂

Material collected: 8♀ + 17♂ from A. narinari ; 6♀ + 1♂ from A. bovinus ; 2♀ from R. javanica ; 1♀ from R. ancylostomus ; 2♀ from R. alba ; 61♀ + 10♂ from S. africana ; 3♀ + 4♂ from R. acutus ; and 15♀ + 11♂ from C. taurus .

Voucher material: 3♀ + 3♂ ( SAMC-A099209 ) from Mobula kuhlii (Müller & Henle) deposited in the Iziko South African Museum , Cape Town, South Africa .

Adult female ( Fig. 24A ) genital complex almost as long as wide; abdomen 1-segmented, slightly shorter than genital complex, longer than wide; antenna (a2) with spinuous proximal process (arrowed) ( Fig. 24B ); post-antennal process (pap) elongate, slender, slightly curved ( Fig. 24B ); maxillule with dentiform posterior process (mpp) elongate ( Fig. 24B ); sternal furca small with slender almost parallel blunt ending tines ( Fig. 24C ); leg 1 last exopodal segment with 3 posterior pinnate setae, terminal seta 4 longer than terminal spines; leg 2 exopodal segments 1 and 2 with distolateral spines (arrowed) lying obliquely across ramus, last segment with distolateral spine (dls) curved across (also inset) blunt terminal outer spine (os) ( Fig. 24D ); leg 4 3-segmented with I, IV spines, lateral spine on compound segment (I) reaching beyond base but less than half length of distolateral spine (II) ( Fig. 20D ) (cf. Pillai 1985; Tang pers. comm.).

Remarks: As indicated by Boxshall (2018) C. chrysophrysi is very similar to C. chiastos (cf. Ho & Lin 2004) especially regarding the structure of the outermost spines on the last exopodal segment of leg 2. However, the adult female of C. chrysophrysi is apparently smaller than that of C. chiastos (2.1 mm ( Pillai 1985) vs 3.15–3.85 ( Boxshall 2018)). The examined specimens were mostly more than 3 mm in length (excluding the caudal rami setae), but the proximal process on the antenna seems to be slightly longer and the post-antennal process slightly more slender, less curved and longer as is the maxillule dentiform posterior process. The length of the lateral spine on the compound segment of leg 4 is reaching beyond the base of the distolateral spine but less than half its length similar to that in C. chiastos ( Fig. 24E , cf. Fig. 71E in Ho & Lin (2004) and Fig. 24F in Boxshall (2018)).

This species conforms to most of the characteristics distinguishing the C. bonito -group of species ( Boxshall 2018) except for the leg 2 second endopodal segment outer margin that does not have large denticles, but rather a fringe of setules (arrowed) ( Fig. 24F ).

This report constitutes new host records for C. chrysophrysi which was originally recorded from Rhabdosargus sarba (Forsskål) ( Sparidae : Acanthuriformes) ( Pillai 1985) and thereafter from M. kuhlii (Müller & Henle) and Mobula alfredi (Krefft) ( Mobulidae : Myliobatiformes ) ( Lebepe & Dippenaar 2013).

Figures

FIGURE 20. Caligus cf. schlegeli Ho & Lin adult female: A. leg 1 exopod distal segment terminal spines 1–3 (arrow = accessory processes); B. leg 2 exopod (arrow = distolateral spine; os = outer spine); C. leg 2 second endopodal segment outer margin (arrow = denticles); D. leg 3 exopod (ds = distolateral spine); E. leg 4 exopod (dls = distolateral spine; I = lateral spine; II = terminal outer spine; III = terminal middle spine; IV = terminal inner spine); F. genital complex, abdomen and caudal rami (arrow = lateral indent).

FIGURE 24. Caligus chrysophrysi Pillai adult female: A. adult female and male, dorsal view; B. cephalothorax, ventral view (a2 = antenna; pap = post-antennal process; mpp = maxillule posterior process); C. sternal furca; D. leg 2 exopod (arrow = distolateral spine; os = outer spine; dls = segment 3 distolateral spine); E. leg 4 exopod (I = lateral spine; II = terminal outer spine); F. leg 2 endopod segments 2 and 3 (arrow = setules).