SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acdd9b41026c6e75510c36b96cc0bc1579f50094ddf4684851ec959e44dc48cd' 
  AND token = '3htuuo5ho8imcy5YrOuLH9qhhK4ci/U8nmQyQ/6d8Kk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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