SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c066ab2c3d3d0ce99b93f7eb1ca6ae8739484cd5012638a56bee29e85c7ab9b5' 
  AND token = 'AI2UWzCnsEZ+S+2N2tT8zPvlwLGljCca8dRQTuUMRlU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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