SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72427c39eaf73f4a5eb5d02a85280fdfb9e53253def5b91d47bd3df982683023' 
  AND token = 'K9W3sSrGjq/smXui2gBDlkmU+bvurfJXr/m0hqHRlgg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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