SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6e458e40963ec7b96682de3bcd5c92a3d7f2758f2433a61b577a5512b9ba26a7' 
  AND token = 'lcDZwKAdhIhDBEUEz7nG/+K7IRujz1mr4VMd5FQoV9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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