SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f44c7f7d9dfa826654da8f5d5ad49fec35899c7482cd8732477d9e044cb97de4' 
  AND token = 'LIt0oE/QvyxdvZYaWTJdOU6wswPpM3zhDyyHtdnRPhQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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