SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '38f7ccc93ed9af0d4ba0ac4c1f10faaa43193a192aa503ae9a1dabe3658d2647' 
  AND token = 'fa005tW9Y9M2NLpR4QBi29uLhyv3iIdagZq3b65SNmI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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