SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaec335505652d9f951c24dfebc981518b95ea76cc013fc878419f3fcfc20bde' 
  AND token = 'IQPeif3XxWCUrxBZdoEI7+Ip9+lV4n9gvYQMqbzuzjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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