SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'abf5193ba87f544fb5e88883c51766a8ce0176ce6b50bb42229d8011399a24a6' 
  AND token = 'Z8fumC7MDtEJAi3btmyuPa6auxtc1doGMb3brw4kA/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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