SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa508bdcbb48f62d912ebce7d6ddd362c543c4ad5fc3d70765d11aa68c8b8be1' 
  AND token = 'UGm4cUTZbqzrDQLkQtAQ5CWXv7uEtTa7Sx0ZWLNU/eA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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