SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05465a6dcca37506eb773efab580f14e92c4fb13fadc13f9051bba814682376f' 
  AND token = 'dpvxhrSvDVGvQv+qRlmOPhSAimIbqxZhFj4LvQgCmzA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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