Caryedon serratus and its parasitoids in the Savanna around Lamto,Ivory Coast

In the savanna around Lamto,Caryedon serratus develops, in the beginning of the dry season, on maturing seeds ofPiliostigma thonningii (Caesalpinioideae). A 2^nd generation, and sometimes a 3^nd one, develops in dry seeds. There is no pupal diapause during the rainy season and adults seems to spend this period in a semi-lethargic state. The parasitoid complex ofC. serratus is a chalcid-dominated one. It includes 5 species: one oophagous (Uscana caryedoni) and 4 larvo-nymphal parasitoids. Three species are regular (Anisopteromalus caryedophagus, Bracon sp. andU. caryedoni), the others are sporadic species (Proconura serratocida, Eurytoma caryedocida). Biological data are given for each species.      

Rice hull and caryopsis discoloration diseases

In West Africa, rice is grown in three constrasting ecosystems, upland, phreatic, and lowland, which is characterized by differing water availability and soil properties. These ecosystems influence the predisposition of rice to disease problems, including the grain discoloration complex. Discoloration of the hull was found to be most severe in the upland, less in the phreatic, and least in the water-saturated lowland ecosystem. Caryopsis discoloration, however, showed no consistent pattern in relation to the three ecosystems and was not correlated with hull discoloration, indicating that other factors are involved.     

Interspecific relations of African crocidurine shrews (Mammalia: Soricidae) based on multivariate analysis of mandibular data

Eighteen graded non-metric characters and 30 measurements of the mandible and lower dentition were used to investigate the grouping of African species of the genera Crocidura, Suncus and Sylvisorex. Seventy-seven taxa (species, subspecies and synonyms), including four European species, were represented by one to nine mandibles (147 mandibles in all), and the means of four Pleistocene African species were also included. The metric data were subjected to principal component and canonical variate analyses, and the non-metric data to principal component analysis. Grouping was detected by comparing the results of the three analyses. Six groups are recognized within the genus Crocidura , typified by C. fumosa, C. turba, C. russula, C. fuscomurina, C. hirta and C. flavescens. Sylvisorex is divisible into two groups, typified by S. lunaris and S. granti. The African species of Suncus (but not the introduced species, S. murinus ) form a single group, which is linked to the Sylvisorex granti group. Suncus is closely related to, or convergent with, the Crocidura fuscomurina group. The first non-metric principal component, the second metric principal component and the second canonical variate are significantly correlated. It is considered that these together represent a general trend of evolutionary advance. Phylogenetic relations are discussed in the light of this; Crocidura may be diphylefic.     

Distribution and breeding biology of offshore cichlids in Lake Malawi/ Niassa

Synopsis Lake Malawi/Niassa is the second largest rift valley lake in Africa, with an area of 28 800 km², and an average and maximum depth of 292 m and>700 m, respectively. The lake is well known for the great diversity of fish occurring in the inshore zone. However, the offshore fish community is poorly documented. To rectify this, regular sampling was undertaken over two years, using trawl and gillnets at six offshore locations. This paper reports on the species composition, spatial distribution and breeding biology of the dominant cichlids species from the offshore pelagic zone. Cichlids formed approximately 88% of the offshore fish biomass. Most abundant were two species of zooplanktivores in the genus Diplotaxodon that made up 71% of the offshore fish biomass. An undescribed species, given the cheironym D. bigeye, was mainly found at a depth of 220 m during the day, but moved into near surface waters at night when the moon was full. This species was absent from the shallow regions of the lake. The most abundant offshore species was D. limnothrissa, which was distributed evenly throughout the lake to depths of 220 m. A less common offshore zooplanktivore was Copadichromis quadrimaculatus that formed 5% of the biomass and was confined to the upper 100 m of the water column. The main piscivores were in the genus Rhamphochromis and formed approximately 10% of the offshore fish biomass. The two dominant taxa were R. longiceps and the large Rhamphochromis group, and both were more common in the southern half of the lake. The former occurred mainly in the upper 100 m of the water column and the latter mainly at depths of 100–150 m. The length at maturity and fecundity for the dominant offshore species were estimated and seasonal breeding cycles determined from gonad activity and gonado-somatic indices.     

A cladistic analysis ofAnisopappus (Asteraceae: Inuleae)

A cladistic analysis of the genusAnisopappus (Asteraceae: Inuleae) has been undertaken. A hypothesis of species interrelationships in the genus is presented for the first time. The analysis also includedArctotis (Arctoteae), used as outgroup, and five additional genera from theInuleae: Geigeria, Calostephane, Asteriscus, Buphthalmum, Pulicaria, andInula. It is concluded thatAnisopappus is a monophyletic group situated at the base of the tribe, diagnosed by, e.g., their obtuse stylar sweeping-hairs. The species with acute sweeping-hairs were found to be derived within the genus. Problems concerning species delimitation, biogeography and character evolution in the genus are briefly discussed.     

A framework for the analysis of gender,intra-household dynamics,and livestock disease control with examples from Uasin Gishu district,Kenya

As livestock disease control programs in Africa begin to rely more upon para-professionals and livestock producers as deliverers of animal health care services, understanding the role different household members play in providing animal health care becomes increasingly important. This paper presents a framework for the analysis of gender aspects of livestock disease control based on a similar framework developed by Feldstein and Poats (1989). The utility of this framework is illustrated using household-level data collected from a district in central Kenya. Adult women and elderly men in the sample have primary responsibility for livestock care, and are therefore well placed to diagnose illness. Dipping and spraying of animals to prevent tick-borne and other diseases is the primary responsibility of adult males. Decisions regarding use of milk from the morning milking are more likely to be made by adult men. It is morning milk that is most often sold. Adult women, however, make decisions about use of evening milk, which is most often kept for household consumption. Knowledge of livestock diseases did not appear to vary significantly by gender, although some elderly men did possess extensive knowledge of indigenous disease categories and traditional remedies. The importance of recognizing gender issues in planning and implementing livestock disease control programs is discussed.     

Tropodiaptomus zambeziensis,T. bhangazii and T. capriviensis,three new species of Tropodiaptomus (Copepods,Calanoida) from southern Africa

Three new species of Tropodiaptomus from southern Africa are described, Tropodiaptomus zambeziensis, T. bhangazii, and T. capriviensis. Type localities are a rice paddy on the Zambezi river delta, a coastal lake in Zululand, and temporary pools in Bushmanland and the eastern Caprivi in Namibia. Speciation of Tropodiaptomus in the warm inland waters of southern Africa is much more extensive than was formerly realised.     

Temperature-related distributions of Metadiaptomus and Tropodiaptomus (Copepoda: Calanoida), particularly in southern Africa

Updated locality records of species of Metadiaptomus and Tropodiaptomus on the African continent confirm the generally disjunct distribution of these two taxa as recognised by Dumont (1980) in North Africa. Distributional data for southern Africa reveal little range overlap between these two genera. Apart from two south western Cape taxa, species of Metadiaptomus are largely confined to upland, higher latitude, semi-arid or arid warm subtemperate regions, while species of Tropodiaptomus generally occupy moist, lower-lying, lower latitude subtropical regions. Separation along latitudinal and/or altitudinal axes implicates temperature as a controlling factor, while separation on the precipitation axis suggests the importance of habitat permanence. Using a multiple regression equation derived for African waters to predict water temperature from latitude and altitude, it is shown that the two genera tend to separate around the 20 °C mean annual temperature isotherm. Additional factors influencing distribution (habitat permanence, water quality, competition and predation) are discussed.     

A nested parasite species subset pattern in tropical fish: host as major determinant of parasite infracommunity structure

The number of monogenean gill parasite species associated with fish hosts of different sizes is evaluated for 35 host individuals of the West African cyprinid Labeo coubie. The length of host individuals explains 86% of the total variation in monogenean species richness among individuals. Larger hosts harbour more species than smaller ones. The existence of a hierarchical association of parasite species in individuals of L. coubie is demonstrated. Monogenean infracommunities on larger fish hosts consist of all species found on smaller hosts plus those restricted to the larger size categories, suggesting some degree of compositional persistence among host individuals. The findings provide strong support for an interpretation of the relationship between monogenean parasite species richness and host body size in terms of a nested species subset pattern, thus providing a new record of repetitive structure and predictability for parasite infracommunities of hosts.After 15/01/1995, ORSTOM, BP 165 97323 Cayenne cedex Guyane France     

Natural levels of fungal infections in grasshoppers in Northern Benin

The infection of grasshoppers by naturally occurring, entomopathogenic fungi was monitored at two sites in Malanville, northern Benin, Africa. Grasshoppers were collected and recorded from the sites between June and December 1992 and all of them, barring the first instars, were incubated in ventilated cages. At the first site, 1343 individuals of 35 grasshopper species were incubated, and at the second site, 857 individuals of 36 grasshopper species were incubated. Three hyphomycete fungi (Deuteromycotina: Hyphomycetes), Metarhizium flavoviride Gams and Rozsypal, Beauveria bassiana (Bals.) Vuillemin and Sorosporella sp. were found infecting grasshoppers. The average incidence of M. flavoviride infection was 2.9% and 1.8% at the two sites for all host species. M. flavoviride sporulated on most grasshopper cadavers within 10 days of collection. B. bassiana and Sorosporella sp. were only collected from one and five grasshopper individuals respectively. A significant difference was noted in the time to death of small grasshopper species infected with M. flavoviride compared to larger species. At one site, M. flavoviride infection was positively correlated with rainfall during the 10‐day period in which samples were taken.