SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '673f070386159c5bd1aa9471827c779612faa4ca65c003db603f30edb5576d91' 
  AND token = 'Z+t6wQtWnbjCNATrH1YG/YieB1jglgx/CHCc8rw+0Xc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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