SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd969ec945535ae1250ce88dbe78c95dacab212f7d292dd7006b71dad7125484d' 
  AND token = 'VDtrs4kMAvq8Pb3Ya03WC++P/guO6hUE1jUITmjYOYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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