SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34aacecc08cf25ecbd4b6a3fd7158907dc7ac8375370ab1ae027e51d79bfb08a' 
  AND token = 'Gxn9pPAzt5V8PoZsOP490K884klJqIaXX7B3nDDWVeM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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