SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '961d969288a14b2dd64ba750b21a94903ba61f52762ce5f35d33778dbcb9834d' 
  AND token = 'KKCRzusUZ5B3EDaQNHbyFjNLpey9gnJXrXcIw2ERcqM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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