SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9000bd9de3def82ef0a7412b609e3bc7710aa6572c5eb96d7d28d9acbcbee2c1' 
  AND token = '2LqqkCYxnHFjAVbQXi7qNHft4DwYdHhYyYFkaIBqYVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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