SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4173be463b71cd7dc2c99489294680d74225127422a764f079dcc7739e422f8f' 
  AND token = 'ZCw+vRntyO1U1nlkuyOhtshODVDxru6dxe998wqAk3A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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