SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6902b57a351590b42280a2e09b85721f72a912827388cf1630af18ce65d04cda' 
  AND token = 'A41soMmIcmQt6wAE09q1P/5DeDkmziwMN9xplR6soEQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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