SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba63a715147f54022a42a3bb4681ffb96129fab832e3c7a7da0f88f942a1c716' 
  AND token = 'rwhfzYtUa4Rk+G54nSZgjVX5m4J6toNdLp+hAffXgQU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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