SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c89de7df2514ded3c195348c91fbcfc14fe912c17c1d96df10973244cbfcfb6f' 
  AND token = 'dwFZYslsp2O2NxE7F7dUyjsKtjqpeFVmO9IgIFD+m2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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