SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '577ad6a3eade53cd4cc55ff9f0c6377a24260f456bf1d6dd38d40617bbd0ba2b' 
  AND token = 'ZIAQOG08rIvL8BLLFb5jcwa5m+kpv0z68eXopJrhWSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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