SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da5713d19fd8f5e8f64c3943e9202b46663facf3b7be9598294031d1bb366019' 
  AND token = 'uha6SXSdaCSoSmQYmylJNureOOusjvkwHzG0Oo/vn5o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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