Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5df16aa9b46d49dfd7bab54303528334206a8e610985ba3014389999304e77ab' 
  AND token = '5bhkOoL/MgT4IGol/mFLkj+VMN+XDEg29JCOPtl1S1A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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