SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db8ccf9e9e2c20e7ddaf55eebe695b1304b63adb6127d24f447c2317252b6d13' 
  AND token = 'hnzENgXACJYVMFg6B9B653VraGKBfl+Z1eJfQf9h9MY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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