alloscutum

Etymology

From Ancient Greek ἄλλος (állos, “other”) and from Latin scūtum (“shield”).

noun

1. (zoology) the flexible part of the dorsal body wall behind the rigid scutum in a hard tick, particularly a female, — the alloscutum is the part of the body wall that must stretch to accommodate the blood that the tick swallows when it engorges in preparation for laying eggs.
   Powerful muscle groups are also present in the alloscutum of the female, nymphal, and larval Ixodid ticks, through which the tick is able to redistribute the centre of gravity and regain an upright position when it falls into an upside-down position. 2008, Heinz Mehlhorn, Encyclopedia of Parasitology