SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee996753203e5de2497218a822521dd3afcd3e6f7a7a150aa743ab4a6cecacc8' 
  AND token = 'AeOWs3YRJgbRWiEcyFQTi365ovNMdkTuHNTocI3esRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}