SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0354186e2efbbc437d178f1536c54e2db39ac5c2623cfcdd90ff2597ecedb360' 
  AND token = '9XwYBLIoXjOu9agVJ8oESfBnWV2+avGxmtleF4yKNxY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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