SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ca0fc8ba9e96c95b90dea9fb35cce22dad9d06e259b143a7a24dd570e0d1d3e' 
  AND token = 'WmhLnd/cfpR3n0MkNXOC57PqdYUDxPm7Iyy/+gxJmVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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