SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fe5406103b13e9cd3364350d2177b7604fb9eb81789f670af784d0c69d080e1' 
  AND token = 'Mn36C7S6sVCXHbLmdr+C8K7ah0Bu1bkv5VKqi33iFZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}