SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9221e2c941d3743cb702d03d5d7bea8018fa21bcd999df98f2b87dc95723c8bb' 
  AND token = 'SdbxFT62IPnSzF1o3uCsBs3VbLP1/4AJBYpSfDL1aLU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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