First Gambian Ricinulei (Arachnida: Ricinoididae): northernmost African record for the order

摘要

Ricinulei is an arachnid order of great antiquity with fossils of the extinct families Curculioididae and Poliocheridae known from the Pennsylvanian (c. 300Ma) of Europe and North America (Selden 1992). However, extant species (Ricinoididae) are knownonly from Africa (Ricinoides) and South and Central America (Cryptocellus and Pseudocellus), with species of the latter genus extending northwards to Mexico and Texas (Naskrecki 2008). In Africa, ricinuleids are restricted to the western tropical regionand have been known from material collected as far back as the late 1700s (Tuxen 1974), although they are not frequently encountered. Eleven species are known from the region, with the most recent one described from Ghana by Naskrecki (2008). Within West Africa they have been recorded from a relatively narrow area (Fig. 1), ranging from Guinea-Bissau to southern Cameroon and also including Ghana, Guinea, Sierra Leone, Republic of Congo, Ivory Coast, Togo, Equatorial Guinea and Nigeria (Legg 1977ab, 1982, Tuxen 1974, Naskrecki 2008). Here we provide the first record from The Gambia, which also represents the northernmost African record of the order.