SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fa2fd8fccd00a6f30f57127b903ef6dc71bbe04cfc34497dba7024ce3bb12844' 
  AND token = 'CE3ZC1CVnMsuUukesXwIFTbVeACLjABz2zNUtQ8PeSs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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