SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bed39d370cca2f04a398dffd6ea2ae143395d802d3843e25955f199ea912b1d' 
  AND token = 'HdJTzehk2ZVFf/VilIxlmAshbE4Qa4whAVRUE9kdl/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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