SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18ab01f343dc342eb1bb09f5899e7f3b196e29a2bf004758b7490276dd800fa5' 
  AND token = 'mSGc5+esN5pNPjyK4DpPve10B/HrrGE/wizHWz/OYK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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