The term 'Irish shrimp' seems to have come about to differentiate them from the likes of the Ally's Shrimp family, Flamethrowers etc that are more recent developments. Although there are certainly many different Irish patterns, of which the Curry's Red shrimp is generally thought to be the archetype, it's worth pointing out that by no means all of them are Irish - the Usk Grub and Black Shrimp (which originated on the Ness) being two that have been around for many years. Strictly speaking, it might be more accurate to talk of 'traditional' shrimps flies to differentiate them from the more modern styles.
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