SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '656ddf744255cee516d25a0084b36e8c714d8eed32ac81d259e321115e6dfb2b' 
  AND token = 'IPWsq6RoBzz1W6uXPwRpfvnBEXjdXUSjYpUTYWsKpU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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