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Scale insects (Hemiptera: Sternorrhyncha: Coccomorpha) feed on plant sap; some are damaging pests in agriculture and forestry. However, the scale insects found in continental Africa have not been extensively studied and the available means of identification are incomplete. This synoptic work, the second in this series, covers the six archaeococcoid scale insect families found in continental Africa: Kuwaniidae, Margarodidae, Matsucoccidae, Monophlebidae, Ortheziidae and Putoidae. The work provides identification keys to a total of 29 genera and 137 species, and a checklist for each family. Pseudaspidoproctus zimmermanni (Newstead) (Monophlebidae) is transferred to Aspidoproctus, as Aspidoproctus zimmermanni (Newstead), comb. n. Praelongorthezia praelonga (Douglas) (Ortheziidae) is recorded from Gambia for the first time.

The Bemisia cassava whitefly complex includes species that cause severe crop damage through vectoring cassava viruses in eastern Africa. Currently, this whitefly complex is divided into species and subgroups (SG) based on very limited molecular markers that do not allow clear definition of species and population structure. Based on 14,358 genome-wide SNPs from 62 Bemisia cassava whitefly individuals belonging to sub-Saharan African species (SSA1, SSA2 and SSA4), and using a well-curated mtCOI gene database, we show clear incongruities in previous taxonomic approaches underpinned by effects from pseudogenes. We show that the SSA4 species is nested within SSA2, and that populations of the SSA1 species comprise well-defined south-eastern (Madagascar, Tanzania) and north-western (Nigeria, Democratic Republic of Congo, Burundi) putative sub-species. Signatures of allopatric incipient speciation, and the presence of a 'hybrid zone' separating the two putative sub-species were also detected. These findings provide insights into the evolution and molecular ecology of a highly cryptic hemipteran insect complex in African, and allow the systematic use of genomic data to be incorporated in the development of management strategies for this cassava pest.

Blood flukes within the genus Schistosoma (schistosomes) are responsible for the major disease, schistosomiasis, in tropical and sub-tropical areas. This disease is predominantly present on the African continent with more than 85% of the human cases. Schistosomes are also parasites of veterinary importance infecting livestock and wildlife. Schistosoma population genetic structure and diversity are important characteristics that may reflect variations in selection pressures such as those induced by host (mammalian and snail) environments, habitat change, migration and also treatment/control interventions, all of which also shape speciation and evolution of the whole Schistosoma genus. Investigations into schistosome population genetic structure, diversity and evolution has been an area of important debate and research. Supported by advances in molecular techniques with capabilities for multi-locus genetic analyses for single larvae schistosome genetic investigations have greatly progressed in the last decade. This paper aims to review the genetic studies of both animal and human infecting schistosome. Population genetic structures are reviewed at different spatial scales: local, regional or continental (i.e. phylogeography). Within species genetic diversities are discussed compared and the compounding factors discussed, including the effect of mass drug administration. Finally, the ability for intra-species hybridisation questions species integrities and poses many questions in relation to the natural epidemiology of co-endemic species. Here we review molecularly confirmed hybridisation events (in relation to human disease) and discuss the possible impact for ongoing and future control and elimination., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Hybridization is a fascinating evolutionary phenomenon that raises the question of how species maintain their integrity. Inter-species hybridization occurs between certain Schistosoma species that can cause important public health and veterinary issues. In particular hybrids between Schistosoma haematobium and S. bovis associated with humans and animals respectively are frequently identified in Africa. Recent genomic evidence indicates that some S. haematobium populations show signatures of genomic introgression from S. bovis. Here, we conducted a genomic comparative study and investigated the genomic relationships between S. haematobium, S. bovis and their hybrids using 19 isolates originating from a wide geographical range over Africa, including samples initially classified as S. haematobium (n = 11), S. bovis (n = 6) and S. haematobium x S. bovis hybrids (n = 2). Based on a whole genomic sequencing approach, we developed 56,181 SNPs that allowed a clear differentiation of S. bovis isolates from a genomic cluster including all S. haematobium isolates and a natural S. haematobium-bovis hybrid. All the isolates from the S. haematobium cluster except the isolate from Madagascar harbored signatures of genomic introgression from S. bovis. Isolates from Corsica, Mali and Egypt harbored the S. bovis-like Invadolysin gene, an introgressed tract that has been previously detected in some introgressed S. haematobium populations from Niger. Together our results highlight the fact that introgression from S. bovis is widespread across S. haematobium and that the observed introgression is unidirectional., Competing Interests: The authors have declared that no competing interests exist.

Five species in five genera of extinct endemic rails have been described from the Mascarene Islands of Mauritius, Réunion and Rodrigues: the Mauritian Red Rail or Poule Rouge Aphanapteryx bonasia; Mascarene Coot or Poule d'eau Fulica newtonii; which occurred on Mauritius and Réunion; Réunion Wood Rail Dryolimnas augusti; Réunion Gallinule or Oiseaux bleu 'Porphyrio caerulescens'; and Rodrigues or Leguat's Rail Erythromachus leguati. All are known from fossil remains and/or from contemporary accounts and illustrations. A sixth species of rail Dryolimnas sp. nov. is described herein from fossils from Mauritius, but was not unequivocally previously reported in the contemporary literature. This paper provides an analysis of the Rallidae of the Mascarene Islands based on existing and newly discovered fossil remains, and details historical reports and accounts. Comprehensive osteological descriptions and synonymies are also included. Their ecology and extinction chronologies are interpreted from historical ev-idence. The relationships of Aphanapteryx and Erythromachus are unresolved, having clearly been isolated for a considerable time; the middle Miocene is the earliest their ancestors could have arrived on the Mascarenes, but this may have happened more recently. Mascarene derivatives of Fulica, Porphyrio and Dryolimnas are of much more recent origin, and appear to have originated in Africa or Madagascar. All terrestrial rails on Mauritius, Réunion and Rodrigues, were probable victims of cat predation following their historic introduction to the islands, whereas over-hunting by humans was probably the primary cause of extinction of 'Porphyrio caerulescens' on Réunion. The only extant rail on the Mascarenes today, the Madagascar race of Eurasian Moorhen Gallinula chloropus pyrrhorrhoa, is a recent arrival, having colonised Mauritius and Réunion after the extinction of Fulica newtonii.

Paragonimiasis, human lung fluke disease, is a foodborne anthropozoonosis caused by the trematodes assigned to Paragonimus and is regarded by the World Health Organization as a Neglected Tropical Disease (NTD). The life cycle of this medically important parasite centres on a complex freshwater biological community that includes two intermediate hosts: a mollusc and a decapod, usually a brachyuran. Although there is a perception that the biology, symptoms, diagnosis and treatment of Paragonimus is well understood, in reality, this is not the case, especially in Africa. Much remains unknown concerning the life-cycle of the parasite, its transmission, the current epidemiology of the disease, diagnosis and the effectiveness of treatment. Furthermore, cases of paragonimiasis may be misdiagnosed as resistant tuberculosis (TB) because of the similar pulmonary symptoms and no remission after anti TB therapy. The endemic foci of human paragonimiasis in Africa have been reported mainly in the forest zones of Upper Guinea (Liberia, Guinea and Ivory Coast) and Lower Guinea (Nigeria, Cameroon, Equatorial Guinea and Gabon). Despite the perceived medical importance of paragonimiasis, relatively little attention has been paid to this NTD since its discovery in Africa in the 1960s. This review focuses on the current understanding of the life cycle and transmission of Paragonimus in Africa, discusses its diagnosis and public health importance and highlights many outstanding gaps in the knowledge that still exist for this NTD.

Novel flaviviruses that are genetically related to pathogenic mosquito-borne flaviviruses (MBFV) have been isolated from mosquitoes in various geographical locations, including Finland. We isolated and characterized another novel virus of this group from Finnish mosquitoes collected in 2007, designated as Ilomantsi virus (ILOV). Unlike the MBFV that infect both vertebrates and mosquitoes, the MBFV-related viruses appear to be specific to mosquitoes similar to the insect-specific flaviviruses (ISFs). In this overview of MBFV-related viruses we conclude that they differ from the ISFs genetically and antigenically. Phylogenetic analyses separated the MBFV-related viruses isolated in Africa, the Middle East and South America from those isolated in Europe and Asia. Serological cross-reactions of MBFV-related viruses with other flaviviruses and their potential for vector-borne transmission require further characterization. The divergent MBFV-related viruses are probably significantly under sampled to date and provide new information on the variety, properties and evolution of vector-borne flaviviruses., (Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.)