SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '292243acfee0a8fd120ef016b5ea6459a4fc1b9d6721023956830a77fed8a2fd' 
  AND token = 'dUzuz8LdyTDdKII3nXmOXG9KmSV0pI+5R8UMyoV3XTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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