SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b7affc155fd8ac195dd80bf00d9377414bbf5f8f1d63626434f1cde91bc804e' 
  AND token = '2HdbOg2qWG/vcgREaI9wARGnB67+2GoMwmqrAuZLhyE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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