SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c052781a5e4cb5728df5fb53fc2b33358c345dfa2cd7f7f4299257cae331b9b4' 
  AND token = 'pgIKBqKoZ/xXdBSjtZUzTyXOH26A1l7l0bTHJM/BxiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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