SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '83c37de8fc1181e7c79e529b26044b1db5beabe0658e1ff38713340698f5cc38' 
  AND token = '99wDhnxzfRvHJAONq4hxR9yLWwSNFtRhorryMJ6wQ00=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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