| ‘Marconia’ hamiltoni s.l. is known from two discrete mountainous areas in Malawi, i.e. the (southern) Mt. Mulanje complex, and the (more northern) Zomba Plateau s.l. These uplands are separated by about 65 km of lower lying land with different types of vegetation and climate. Material from these two regions may be distinguished as separate species, the southern populations having comparatively small and broad shells with some apertural dentition (‘M’. hamiltoni, lectotype designated), while the northern populations have noticeably larger and more slender shells with a more reduced apertural dentition (‘M’. malavensis). Discussion of the type localities for both taxa shows that these are either localized in an unlikely place (‘M’. hamiltoni) or unclear... |
