SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ec87595c48df29d0e818ca74403ca35fb60b64a9d69e06ea269a05df57c50abd' 
  AND token = 'udGJcxGTtco4FxpcgUTxItoBSZKnW1NsHbUiHjmyumg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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