SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e9138b890e79449e896201f31c247e7b2f58c0abe059c2b1ed01bd13d151e45f' 
  AND token = 'EPghD8PGwxGJo9FxQ9e5puOIfO4YCHuY2PqOwA+Z3Q0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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