SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '47f9c4779915248f2905a4c5f72e12d694901d92983d5171df742af13b8514ef' 
  AND token = 'InDqdYHasaJHsrsyym8s3vt2MAikrdBLljvbFRq6Gxk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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