SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '130412fd572a7b7324865ef971d51a2ecf9a07be09c8a3a2619a4d2afb946feb' 
  AND token = '4632bSa8hWrazTrm+md/KSP1MQd5r12cS0Bj8H9MJqk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}