SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4122b4e4415dc0b3a736e7940be9552371b1cd25f933c0ead99c9160c19c6fa1' 
  AND token = 'OnNYaJz8A0rXahFxTb98QtSDHOKVrxkbF48OXhN3DKM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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