SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3151a8b82a288c44093ac2f0c01d388996b6a57005286540ac6daa9354ea4625' 
  AND token = 'Dj0wTpOua7M47U6FPRFfgCrg22Ql2LwBzGa41HTnrSY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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