SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9252a24ee2ba8e8764e59bf09a54fc6c90e26effb9ba725fc42686b0ad174fe' 
  AND token = 'C1JCi3uGevlC/g8LBCzx0wYp6ZQkVmxbut5JbHi4qRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}