SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8894d4288d55b08e0c055a5f284a9f1ce7ce3d1bd953bae918bab1242a743a7e' 
  AND token = 'vT/+3uzbLRwQfqfZMI0o7k9DnLS2sGB5VH9mf7x+K40=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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