SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '209102d706ed4d9bdf472dc8b423faf03b508160a741ff5baf7c46e4fe41f2c7' 
  AND token = 'zWxNvpJCySX+cC7qJ1HZTrLPoFrww8Y4kqPq8B1VDho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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