SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bacc6a1e797f369269619954029e847c6be63e7208f6f1947112c1ad69cabf3b' 
  AND token = 'WnhIbODbincIYk85+9bPfgvSUqAOm6N1hZSOJtqJlMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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