SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '744763c6f1f591d6af15f80e416c0d7e534a45c130b7c6490491abb06900d322' 
  AND token = 'D0CagVs8rbdpJJwbx8Dg/UbkwQYh8+Sx+KnjcqQIDZc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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