SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '864d43ad8def8921475536a0689f4ecd1390e1a17a4deabff4044c83edfaa060' 
  AND token = 'oApUyNoW7qaEc2cuRX/s1ZEewKVgzYMojdur03SqYWo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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