Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcb1a88391ba9bda5b40d50eb28bf2efeaf29b4952bc7edc51a6d93c1871ea21' 
  AND token = 'aRrMBFnKARWTVwj460rv3cbIHVPjT9QJXgK3POL5urQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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