SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c46f82b530ea2b483fad6747db9cd50cb77151eb6cfac12dfa85d5a11f17179' 
  AND token = '/xu6YFZ/oAFxAEuXRZZPiTm+9/+GeXwKlZbIyw+8Rqw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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