SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '659f372d4bb53118e5d55b1b1d0d43db0897309d88cf902d6cf56437ba42a85e' 
  AND token = 'K0wMw94hYJvJxJgihsxLusxt32rn/0mAtd2vjQ/+0X4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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