SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c2a713100569a7ce454faf2bfb6b5a87e4f268c6b85361a886256c22f6453f2' 
  AND token = 'B0RURSovtVL50S6RJv2ediXN0pb46Kv46EjcYUU2wl8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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