SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '607c417b3f0b32711a229941eda7c80cdbe0587da5185ea24fecc11fcd3d86ec' 
  AND token = 'cTvx2+etIWJq1LNtPi3ZhnaiDrWsXWxXEkgtB3A8RdU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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