SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cf77e6ee72a960d79a9f2fbede2c247def96ec7088c0d9ad645408b1ae216740' 
  AND token = '/gOe5ZbeRcJGmdGBobO5bOAHmqJKg1oATzTdmOku2m4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00076

JSON explain

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