SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acb49d1164f94c658a41427ea27a685ecfc78ad2b1dd066dca26a8f51746f142' 
  AND token = 'dIelvzSnCYVL/4DvPMvJHsilvignRd0/WDw9hmSWSlE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}