SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '498b43e4c1be12b9dbbec8a32cff04935bb5cf26598cd68418fa884b4e99cea3' 
  AND token = 'o02eHdAGh3WtPlq+DflQabHvIyZ8uHADQKgWDcNqWxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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