At first glance
it looks like only one digit (digit 1, including its big ungual) is visible in the manus of Icarosaurus (Colbert 1966). But add some colors to the bones (DGS) and the extra bits and pieces make themselves known. Apparently the fingers were tucked under the metacarpus (Fig. 1). The reconstruction matches the manual phalangeal patterns of other kuehneosaurs, including Coelurosauravus, Kuehneosaurus and Xianglong, adding confidence to the reconstruction that also had continuous PILs.
Colbert, Edwin H. (1966). A gliding reptile from the Triassic of New Jersey. American Museum Novitates 2246: 1–23. online pdf