SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a64cf789298bcdd214ec3e06c5bd331380434926b710ce560a3d957c140e14cc' 
  AND token = 'qFarZ5yfxsJpZ9egbFCuYmJ1W/p+5HVNBC/pYyKpFvU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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