SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba9c17b609f12487be47b1614415d8bd01115c3d5c2d8ce91683c2314ea45ae4' 
  AND token = 'bFaB82ERbRdZkQLHIbtQ9DrWGZCZUTOGkiZ/2WoJZdg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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