SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45329ddd1f7a57b3ca5387dd32baf1e52d9898a534a9984a9b52b2d45ba838bb' 
  AND token = 'abUDHeBFQhKsCHFZJ8NxeQig7zSeanBUCMBbVmWMwxE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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