SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d13b88821f4b814a23786f7a3de504cc6cc45408bc33d1395a5e5756d8b6c10' 
  AND token = '6kZWIdZsSQma9qtG0gh0xG2vXIJBHW8H9+YDPbon+Hg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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