Characteristics of a Microsporidium (Protozoa: Microspora) Infecting Grasshoppers (Orthoptera: Pyrgomorphidae) in Cape Verde, Africa

ABSTRACT A light and electron microscopic study was conducted of a microsporidium isolated from the grasshopper Pyrgomorpha cognata Krauss, 1877 collected in Santo Antão and Santiago Islands, Cape Verde. The evidence suggests that although there are some differences, such as tissues affected and size of spores, the organism appears conspecific with Nosema pyrgomorphae Toguebaye, Seck & Marchand, 1988, which was described from another species of the genus Pyrgomorpha Audinet-Serville, 1838 in Senegal. However, in addition to the differences in tissue specificity and size of spores, light microscopy studies also revealed some stages of the pathogen (uninucleate bodies and plasmodia) apparently not previously observed in N. pyrgomorphae .     

THE EFFECT OF SODIUM CHLORIDE CONCENTRATION ON GROWTH AND EGG LAYING OF HELISOMA DURYI, BIOMPHALARIA ALEXANDRINA AND BULINUS TRUNCATUS (GASTROPODA: PLANORBIDAE)

Helisoma duryi, Biomphalaria alexandrine and Bulinus truncatuswere maintained in media with seven different sodium chlorideconcentrations ranging from 0.6 to 32 mM. Growth of H. duryiwas significantly reduced only in the 32 mM NaCl treatment,while no significant effects were observed in the net reproductiverate or in egg-laying rates. Bulinus truncatus showed optimalgrowth within the range of 1 to 8 mM NaCl and the net reproductiveand egg-laying rates were reduced in the 32 mM NaCl treatment.Growth of B. alexandrina was reduced in the 16 and 32 mM NaCltreatments, while the net reproductive rate was reduced in the16 and 32 mM NaCl treatments, while the net reproductive ratewas reduced in media with more than 2.0 mM NaCl. Hatching ofB. truncatus eggs was not affected by the high NaCl concentrations,while the hatchability of H. duryi eggs was reduced in the 32mM treatment. Survival of newly-hatched H. duryi was best inthe 1 mM NaCl treatment while for B. truncatus survival wasreduced only in the 32 mM treatment. (Received 28 March 1988; accepted 7 April 1989)