SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '922be7fabb4e5bc568c10aff6cc373b029e28fc5f1f8f1871be629ca39601d58' 
  AND token = 'WQDFawKWwcqpaUVK+k5oN936NwZV1nkC+OdoIals9sU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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