SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48f3eb13312f611a71a27cadb2a9ac49d1a9fdbf5aa9f7af35792aafbd179e2f' 
  AND token = 'FjTE9LoNLtwjIoeG8IHHjyppQzmkGP7FqN/+LV/SwWQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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