SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29413a7f6ea7e4b7c942c3d62831b115e728fb46a3a7ccc3adf65c36e793b3ed' 
  AND token = 'tHLKnMRmAnJudibjtA+JUyHpkx0iSnsuE4KVC8rXkVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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