SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '167655cb86170e099b5541feacd3a4f8ec5a1ca9b828e799ca07bfc5675bd09c' 
  AND token = 'GMbHujZv9E1qjUDDnOdsvikXp+7TMQM/FTu18kmXwFM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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