SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72f0fcee77130cbed2bb721b86a34e8ad93ac23358027c131c8344960db61258' 
  AND token = 'Xb6KYQJeQQ5npcJCpEkYtjCOgImfsEicTMaoAIorV5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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