SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28c1d9c8804a11ac8305d4dc98ad826f2a79ab8182f346b9f7836d34b45b93be' 
  AND token = 'KC+eRfwYIJIPppLgesupc/4A4ZTwsqyQO24RYjTCE/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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