Branchotenthes robinoverstreeti n. gen. and n. ap. (Monogenea: Hexabothriidae) infects the gill filaments of the bowmouth guitarfish, Rhina ancylostoma Bloch and Schneider, 1801 (Rhynchobatidae) in the southwest Indian Ocean off Trafalgar, South Africa. The new species is most easily distinguished from other hexabothriids by the combination of having a symmetrical haptor, C-shaped haptoral sucker sclerites that are approximately equal in size, haptoral suckers that are equal in size and arranged in 3 tandem pairs that each straddle the longitudinal axis of the haptor, glandular-walled vasa efferentia that are dilated in the distal portion and unite medially before connecting to the vas deferens, a thick-walled male copulatory organ with an oblong proximal portion and an unarmed and finger-like distal portion, parallel vaginae that each possess a thin-walled and sperm-filled proximal portion that is strongly sinuous as well as a thick-walled and musculoglandular distal portion that extends sinuously anteriad, and an egg with a filament at each end. This is the first report of a hexabothriid from asharkfin guitarfish (Rhynchobatidae). A key to the genera of Hexabothriidae is provided.

Worldwide there are more than 12000 species of copepods known, of which 4224 are symbiotic. Most of the symbiotic species belong to two orders, Poecilostomatoida (1771 species) and Siphonostomatoida (1840 species). The order Siphonostomatoida currently consists of 40 families that are mostly marine and infect invertebrates as well as vertebrates. In a report on the status of the marine biodiversity of South Africa, parasitic invertebrates were highlighted as taxa about which very little is known. A list was compiled of all the records of siphonostomatoids of marine fishes from southern African waters (from northern Angola along the Atlantic Ocean to northern Mozambique along the Indian Ocean, including the west coast of Madagascar and the Mozambique channel). Quite a few controversial reports exist that are discussed. The number of species recorded from southern African waters comprises a mere 9% of the known species. RÉSUMÉDans le monde, il y a plus de 12000 espèces de Copépodes connus, dont 4224 sont des symbiotes. La plupart de ces espèces symbiotes appartiennent à deux ordres, les Poecilostomatoida (1771 espèces) et les Siphonostomatoida (1840 espèces). L'ordre des Siphonostomatoida comprend actuellement 40 familles, qui sont pour la plupart marines, et qui infectent des invertébrés aussi bien que des vertébrés. Dans un rapport sur l'état de la biodiversité marine en Afrique du Sud, les invertébrés parasites ont été remarqués comme étant très peu connus. Une liste de tous les signalements des siphonostomatoïdes des poissons marins des eaux sud-africaines (du nord de l'Angola le long de l'Océan Atlantique au nord du Mozambique le long de l'Océan Indien, incluant la côte occidentale de Madagascar et le Canal de Mozambique) a été établie. Quelques rapports très controversés sur le sujet sont aussi discutés. Le nombre d'espèces reconnues en Afrique du Sud ne comprend guère plus de 9% des espèces actuellement connues.

Members of the Siphonostomatoida are associated with either invertebrates or vertebrates. Even though the interfamilial relationships within the Siphonostomatoida are unresolved, it has generally been assumed that those members parasitic on vertebrates form a derived and monophyletic group. Eleven of the families symbiotic on vertebrates have been reported from elasmobranchs. One nuclear genetic marker (18S rDNA) and two partial mitochondrial markers (16S rDNA and COI) were used to estimate the phylogenetic relationship among six families symbiotic on elasmobranchs. The estimated molecular topologies using maximum likelihood, parsimony (unweighted and weighted), and Bayesian analyses are mostly similar. The six families investigated grouped into two major clades, with Kroyeriidae, Caligidae, Pandaridae, and Dichelestiidae in one clade, and Eudactylinidae and Sphyriidae in the other. The molecular topologies are compared with the previous morphological topology and present some support for some of the proposed relationships and alternative hypotheses in the areas of conflict. Valuable information obtained from the study is the indication that the genes used are informative at this level of investigation and can therefore be used in more elaborate future studies. RÉSUMÉLes membres des Siphonostomatoida sont associés soit à des invertébrés, soit à des vertébrés. Même si les relations interfamiliales à l'intérieur des Siphonostomatoida ne sont pas résolues, il est généralement supposé que les membres parasites de vertébrés forment un groupe dérivé et monophylétique. Onze parmi les familles symbiotes de vertébrés ont été observées sur les Elasmobranches. Un marqueur génétique nucléaire (18S rDNA) et deux marqueurs mitochondriaux (16S rDNA et COI) ont été utilisés pour estimer les relations phylogénétiques entre 6 familles symbiotes d'Elasmobranches. Les topologies moléculaires estimées en utilisant les analyses de maximum de vraisemblance, de parcimonie (non pondérée ou pondérée) et l'analyse bayésienne sont assez similaires. Les six familles étudiées se regroupent en deux clades principaux avec les Kroyeriidae, Caligidae, Pandaridae, et Dichelestiidae dans l'un, et les Eudactylinidae et Sphyriidae 1 ) SUSAN M. DIPPENAAR dans l'autre. Les topologies moléculaires ont été comparées avec la topologie morphologique existante et fournissent des arguments pour certaines des relations proposées et des hypothèses alternatives pour les régions montrant des conflits. L'information de valeur obtenue grâce à cette étude indique que les gènes utilisés sont informatifs à ce niveau d'investigation et peuvent donc être utilisés à l'avenir dans des études futures, plus élaborées.

a b s t r a c tOver the past decade, numerous molecular phylogenetic studies uncovered cryptic diversity within the Copepoda, yet very few investigations focused on symbiotic copepods. Here we report mitochondrial DNA cytochrome oxidase I diversity in the cosmopolitan elasmobranch symbiont Nesippus orientalis off the KwaZulu-Natal coast of South Africa. Analysis of partial COI sequences of copepods sampled from a diversity of shark hosts, revealed the presence of two divergent clades. Diversity within the clades does not appear to be structured based on host species, host individual, geographic locality or time of sampling. However, divergence between the two clades seems to be related to host species. Phylogenetic analyses of representatives from the two clades, along with Nesippus spp., Caligus spp. and Lepeophtheirus spp. outgroups, further supports the distinction between the two clades. Future molecular phylogenetic investigations of widespread copepod symbionts most likely will reveal far greater levels of biodiversity than currently recognized.

The caligid genus Pupulina van Beneden, 1892 currently has three accepted species. Two new species, Pupulina cliffi n. sp. and P. merira n. sp., are described from Mobula kuhlii (Müller & Henle) and M. eregoodootenkee (Bleeker) (Mobulidae) caught along the east coast of South Africa. Pupulina cliffi can be distinguished from all the other species by the absence of posterolateral processes on the genital complex, whereas P. merira has very short, rounded posterolateral processes on the genital complex compared to the three previously known species. Additionally, P. merira is the only species with the abdomen only about two-thirds the length of the genital complex and the caudal rami about the same length as the abdomen. A dichotomous key to distinguish the five species of Pupulina is provided.