SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b27d9a4e3d0dbd95bb370c23058adeb7f6cabfd000e5d0771905624976ee1e89' 
  AND token = 'Hp06pA18NvAJd2DmqYyZ52VGecltJZyeNf2LbugjW6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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