SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2b3021db3bc49bd161c41b626abed3fdf640ae86ac6c14f7012f1b9b3c3414b6' 
  AND token = 'GV0D1ktOtfxi8b5aKEB9bmds8ulouwt43wenPRsfpAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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