SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '405be3aa2a16a795ddc5ad3748b31031d00fea8a19118e5cae55e8e5d025bbf1' 
  AND token = 'dzGZsrRrximqMj4ZrI1IYNSZaAV5bHYwdCAGU1FFMfs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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