SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a6c181ddd9a13e5b86654fab7dd121c848984abc8e6f1fef0a7e11e97cd437a' 
  AND token = 'nvh4g5TuQHbuETwSh35x6ZtW8jpuzo+oFjUzDvG4hss=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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