SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0eb9b8427433de596317663ba55cbaddfb236ec9ea48d219105d2f20a06d8bd3' 
  AND token = 'gE+YMkIuGKXnAsuo/9bhJJTo/z8kDPoHcxUmWc5DLSI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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