SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc30d3f96dadc5e0c2171a0455b2b87bdf87a3c86158733368f3699e74d63fcd' 
  AND token = 'gt+6hvo9uV5pXRIUs6R7GZ+vHhQ9pnjVvBGicgDEY0A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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