SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a906deaac4afe175510d8c9b41c3f2c431f1dde45bdedeae95aef8083fd225fa' 
  AND token = 'mIIyyI6E+3pCcMD/cNfRzCoVeqMBNmKBHruj3kz0wjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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