SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '14b52d96db00d086afdc1f75b93fdc9f074bff5a90dd3acc16deb5252ffebe23' 
  AND token = 'VGw6F0T6SGO+hml5RaW9SzJrrjTLY34BlTgo/JJIz4k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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