SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '614994f25085f05871947f40fcb361a526ef9fbd1b8cb94ca8c7f22e053ccb14' 
  AND token = '8XIuVTrivXe0cpfppdJRqoP1ollgI2GUQcmHHNAh21A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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