SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60b138916065df9a139abffa7d7b60d82886b7fda9304c79627d2a40a9566d50' 
  AND token = '//MtP5yAcxJBrhHZcU00IMDcVoztxGqyXerNwe4acEs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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