SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3bdc068587a2f24b9b981e2b8367c9af2f27f9fcfa708fcb0a17a7de30634fd3' 
  AND token = 'QsC9tfeJXo34OjCyfSSlXVk/87/8GRw1XLBGegjrbRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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