SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7de43ba799e4bde5e9051eddc9c36f1cf02720dc5f87f2e301b9283cbf8a2db' 
  AND token = 'a1IkCpOn6uOo5Q2rol9YeoSGDnYxf3iL7lgVpjzJGg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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