SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '540301084006191cdcafa11f9b3af87b0c814ce7a23f98c574d79ac0e78d32b6' 
  AND token = 'XOgwirVYU77mcnprFyNaL2lAfkFELeaTSQHzeRoWCrQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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