SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aeb1e9d9d09bf6399fee7733aa8c46b39eccac4dfff38b797d265b37772daf40' 
  AND token = 'F112qgv3TF+019/YpQ1vyZ7YhZwPywOyJpxyL7ZWp6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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