SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ab6917385a31b17d8ea16dea90962971d3ab43ae3ce9f7a95b3a25756102d7a' 
  AND token = 'gLMxWE1QrMUfBcS1qPInjiH+KuLz9P+u/vYof+P5bjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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