SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84303fb34bd50a325bc69b7b9320d2989253973782c06704ec603aa3a6031493' 
  AND token = 'gugELdTWIQ0Y8MFcCnhNDrkmMBSoZ7hnpmCoIzUogUo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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