SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d1c5f6a75dd1e1ec552ccc0d5c7f71964160eb9233d7c43f5206b8c0d8b9cff' 
  AND token = 'IGJVSf+lpifxAgaXUQ37OQtu59wvvMh9K8zYxi8okQ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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