SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '713538e2e9a7b7c310eae193bc60039dcae0022d9a7721aea47ac67295846737' 
  AND token = 'XurbuVBhLWkeshIq+fBzUc1EkGd+UWjkZi36W0fxYJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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