1 ▁L 1 6 9 - L 1 7 2 , ▁, ▁School ▁of ▁Physics ▁and ▁Astronom y , ▁University ▁of ▁Le eds , ▁Le eds ▁L S 2 ▁ 9 J T , ▁UK ▁ ▁Category : Pro to st ars ▁Category : S ag itt arius ▁( const ell ation ) <0x0A> </s> ▁The ▁blo ody - red ▁my s id , ▁Hem im ysis ▁anom ala , ▁is ▁a ▁sh rim p - like ▁cr ust ace an ▁in ▁the ▁Mys ida ▁order , ▁native ▁to ▁the ▁P onto - C asp ian ▁region , ▁which ▁has ▁been ▁spread ing ▁across ▁Europe ▁since ▁the ▁ 1 9 5 0 s . ▁In ▁ 2 0 0 6 , ▁it ▁was ▁discovered ▁to ▁have ▁inv aded ▁the ▁North ▁American ▁Great ▁L akes . ▁ ▁Distribution ▁The ▁species ▁is ▁native ▁to ▁fresh water ▁marg ins ▁of ▁the ▁Black ▁Sea , ▁the ▁Az ov ▁Sea ▁and ▁the ▁eastern ▁C asp ian ▁Sea . ▁It ▁has ▁histor ically ▁occurred ▁in ▁the ▁lower ▁reaches ▁of ▁the ▁Don , ▁Dan ube , ▁D nie per ▁and ▁D ni ester ▁rivers . ▁In ▁Europe , ▁it ▁has ▁recently ▁spread ▁north ▁west , ▁reaching ▁the ▁Balt ic ▁Sea ▁in ▁ 1 9 9 2 ▁and ▁the ▁United ▁Kingdom ▁in ▁ 2 0 0 4 . ▁The ▁my s id ' s ▁spread ▁has ▁been ▁facil itated ▁via ▁its ▁deliber ate ▁introduction ▁into ▁res er voir s ▁on ▁the ▁Vol ga ▁and ▁D nie per ▁rivers ▁in ▁the ▁