SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c028519bf6fb43f895b6a30aa46adf09670710966d5df7d177c1eba287209c94' 
  AND token = 'NAjwe8IgV4dB65pcCFeugqJKRVeMDzzr+skIbGnE+88=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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