SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48a605b5a54c539010157c686aefddc4685bdc9d79809372bd32d9148177ab90' 
  AND token = 'Tp98zB6XIpmltjVT6+S6XOBzqIIZPKqM3OVHDKGM/ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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