SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3357bdb29952192a66e71bdfebb43f374982d7b9dc26c5c5109de58221b99811' 
  AND token = 'aQw7ayZ9cgHsmPWlQulj67VzGYO5MFvf4oZ+CmOjN4U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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