SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccaca0eedd5b0b6f9e753406fcdc148dbd1ae0959ff4a6c8ec1ce4e1e82c0385' 
  AND token = 'pAYH6DM9ghgrtNs5TFppyuaEzbthWUxoRBpxBL738Tg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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