A revision of the genus Platythelphusa A. Milne-Edwards, 1887 from Lake Tanganyika,East Africa (Decapoda: Potamoidea: Platythelphusidae)

The genus Platythelphusa is revised and six species are recognized. These species are P. armata A. Milne-Edwards, 1887, P. maculata (Cunnington, 1899), P. conculata Cunnington, 1907, P. tuberculata Capart, 1952, P. polita Capart, 1952 and P. echinata Capart, 1952. A seventh taxon, P. denticulata Capart, 1952 is considered here to be a junior synonym of P. conculata. A diagnosis for each species is provided and most are figured from the type. Keys to the families of African freshwater crabs and to the genus Platythelphusa are also provided.     

A new stylochid flatworm (Platyhelminthes,Polycladida) from Victoria,Australia and observations on its biology

There are only four polyclad flatworms currently known from temperate waters of Victoria, Australia, although these turbellarians are common inhabitants of rocky shores. A new stylochid flatworm, Stylochus pygmaeus sp. nov. (Platyhelminthes, Polycladida) or oyster leech is described here from Port Philip Bay, Victoria. This flatworm was observed feeding on three species of barnacles by extending its pharynx over its prey and extruding copious amounts of mucus. Worms also preferred to prey on larger‐sized barnacles regardless of the species. Further observations indicated that these worms deposited eggs at night inside empty barnacle shells. Each eggmass was brooded for several days with the worms only moving off to feed. Each egg capsule contained multiple embryos and after 5 or 6 days, positively photo‐tactic, four‐lobed Götte's larvae emerged. Larvae metamorphosed to juvenile flatworms 1–2 weeks post‐hatching but failed to settle and survive.     

Notes on the occurrence of Talitrus dorrieni Hunt (Crustacea Amphipoda: Talitridae) in south-west England

Summary

The introduced amphipod crustacean Talitrus dorrieni is abundant in terrestrial localities on the Isles of Scilly, and has been found in three previously unrecorded localities in Cornwall. Although widespread on the islands, it is restricted to gardens and cultivated ground on the mainland. The origin of the colonies and the factors limiting their spread are discussed.     

Notes on the occurrence of the introduced landhopper Arcitalitrus dorrieni (Hunt, 1925) on Guernsey,Channel Islands

The introduced landhopper Arcitalitrus dorrieni (Hunt, 1925) has been recorded at various locations (woodlands, private gardens and garden centres, disused quarries) throughout the island of Guernsey, Channel Is. Landhoppers were present in the leaf litter of most of the deciduous and coniferous woodlands with one exception. Although it possessed a well developed litter layer, the oak/mixed woodland at Fauxquets valley was devoid of landhoppers. Landhopper populations were less dense in confierous cf. deciduous, leaf litter. Generally the population density of landhoppers was low (21–300 individual m^-2) compared with other UK sites (due possibly to the study coinciding with the driest summer for 19 years), but was related to the depth of the litter layer. There was also a direct relationship between the total copper content of the leaf litter/soil and landhopper population density even allowing for different litter thickness. While locating an actual original introduction site is problematic, the date of introduction, for reasons discussed in the text, is likely to have been between the early 1900s and 1950.     

Notes on some larval and pupal chironomids (Diptera) from Lake Kariba,Rhodesia

Summary

The effects of hydrolysable tannin and condensed tannin on the feeding of Schistocerca gregaria and Locusta migratoria are described. An attempt is made to explain the different effects of tannins in the presence of different nutrients. The ecological significance of these findings is discussed.     

Taxonomic revision of the seasonal killifish genus Nothobranchius from Zanzibar,East Africa (Cyprinodontoidei: Aplocheilidae)

Nothobranchius guentheri and Nothobranchius melanospilus, the two seasonal killifishes of the genus Nothobranchius occurring in Zanzibar Island, Tanzania, were involved in past taxonomical mistakes and are still misidentified in museum collections. A historical review is herein presented and both species are redescribed on the basis of type material and recent collections. Nothobranchius guentheri, a popular aquarium fish, is endemic to Zanzibar, and N. melanospilus, geographically widespread in East Africa, occurring both in Zanzibar and in continental river basins. These species are distinguished by a series of morphological features not previously reported in the literature, including pre-dorsal length and relative position of the anterior portion of the dorsal-fin skeletal support and vertebrae; number of gill-rakers of the first branchial arch, caudal-fin rays, scales of the longitudinal series, series of scales around caudal peduncle, and vertebrae; frontal squamation; and arrangement and number of neuromasts of the supraorbital series. The present taxonomic revision comprising N. guentheri and N. melanospilus, the oldest species names of the genus in the East African biodiversity hotspot, is important to improve the knowledge of the genus in a region where its taxonomy is still problematic     

A new species of Glyphidrilus (Microchaetidae: Oligochaeta) from East Africa

Of all of the chrysomelid subfamilies, only the larvae of the Megascelinae, along with those of the Aulacoscelinae remain undescribed. The first instar larva of Megascelis puella Lacordaire from Panama is described, as well as the eggs. Larval characters, eggs and oviposition behaviour are used to relate the Megascelinae with the Eumolpinae in support of what is known to date concerning adult morphology.     

The catfishes (Teleostei: Siluriformes) of central Sumatra

The freshwater and estuarine catfishes of central Sumatra draining to the Indian Ocean and between the Rokan and Batang Hari drainages are reported on the basis of literature records, museum material, and recent collections. Eighty-two species in 10 families are recorded from central Sumatra. Hemibagrus velox and Nanobagrus stellatus are described here as new species. Akysis macronema and Clarias olivaceus are redescribed here.     

The occurrence of the genus Ingolfiella (Crustacea,Amphipoda) in South Africa,with description of a new species

Abstract

The occurrence in South West Africa, i.e. within the confines of the Republic of South Africa, of the Amphipod genus Ingolfiella Hansen is recorded. The species is subterranean, is larger than any of the previously known species, and is described as I. opisthodorus sp. n. It is compared with I. leleupi Ruffo from the Congo and Northern Rhodesia. The majority of the specimens seem to be females although none has even a trace of oostegites or brood lamellæ. They exhibit a marked dimorphism of the first pair of pleopods, chiefly in specimens exceeding 14 mm. in body length; a juvenile form of this pair occurs in specimens measuring 12 to 14 mm. A few supposed males, among the last specimens to be collected (in June), are smaller than the supposed females but the two pairs of gnathopods are relatively larger and of a different form.     

Taenia dinniki sp. nov. (Cestoda: Taeniidae) from the striped and the spotted hyaena in East Africa

Summary

Taenia dinniki sp. nov. is described from the small intestine of Hyaena hyaena in Tanzania and Kenya and Crocuta crocuta in Kenya. It differs from T. hyaenae, T. crocutae and T. olngojinei in combinations of characters including the number and size of the rostellar hooks, the distribution of the testes and the number of primary uterine branches.