SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ddbaadda38eef033bf140dd1fb1227c6f1e690cf4aa160a25457653896e23e10' 
  AND token = 'pRuRUtohSzXJtinZINyBC+FEfCvISHbTYYOmb97Pag0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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