SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '362536df863dabce0611e4245d45cea29bbd44f7a0153247645c0f60de9c1980' 
  AND token = 'zzRr7IU1MTi5Ym7FNX/F4+u7z7YFdg2E5i9ORljxof4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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