SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b17fc9594cee43e5f8770643575f37f6109d317aae32e90648551683773e293' 
  AND token = 'IuDsErOHflVt74CA5FDuR00QaYzQf6Jbhn8GBHkvs/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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