Monographis, Attems, 1907

Huynh, Cuong & Likhitrakarn, Natdanai, 2023, First records of penicillate millipedes (Diplopoda, Polyxenidae) from Thailand, with descriptions of two new species, Zootaxa 5383 (4), pp. 514-536 : 523

Key to species of the genus Monographis

The key is for characters observed in adults only, as subadults or immatures may not have as many bacilliform sensilla mentioned in this key ( Monographis mira and M. annandalei have incomplete descriptions published by Turk (1947), and Silvestri (1948), respectively, therefore cannot be included in this key).

1 Antennomere VI with sensilla forming a crescent shape...................................................... 2

- Antennomere VI with sensilla forming a triangular shape................................................... .. 11

2 A gap present between thin and short thin bacilliform sensilla, posterior face antennomere VI........... M. panhai sp. nov

- No gap between thin and short thin bacilliform sensilla, posterior face antennomere VI............................. 3

3 Antennomere VI with more than 15 tall bacilliform sensilla................................. Monographis kraepelini

- Antennomere VI with less than 15 tall bacilliform sensilla.................................................... 4

4 Antennomere VI with more than 10 tall bacilliform sensilla.................................................... 5

- Antennomere VI with 10 or less tall bacilliform sensilla ....................................................... 6

5 Antennomere VI with 11 tall bacilliform sensilla, labral surface setose, anterior setiform process longer than the claw.............................................................................................. M. cattienensis

- Antennomere VI with 11 tall bacilliform sensilla, labral surface not setose, anterior setiform process less than 1/2 the length of the claw................................................................................. M. tamdaoensis

6 Antennomere VI with only seven tall bacilliform sensilla....................................... M. baihualingensis

- Antennomere VI with 8-10 tall bacilliform sensilla.......................................................... 7

7 Labral surface setose.................................................................................. 8

- Labral surface not setose.............................................................................. 9

8 Anterior setiform process longer than the claw............................................................. 10

- Anterior setiform process about 1/3 length of claw................................................... M. sabahna

9 Anterior setiform process longer than the claw................................................... M. thatsonensis

- Anterior setiform process about 1/2 the length of the claw......................................... M. phuquocensis

10 Anterior margin of labrum with a row of acute triangular setae, body length greater than 4.5 mm ............. M. malayna

- Anterior margin of labrum with a row of slender setae, body length about 3mm ........................... M. demangei

11 Total tall bacilliform sensilla less than 24................................................................. 12

- Total tall bacilliform sensilla more than 24...................................................... M. condorensis

12 With three internal tall bacilliform sensilla...................................................... M. yunnanensis

- With five internal tall bacilliform sensilla................................................................. 13

13 Claw robust ............................................................................... M. tamoyoensis

- Claw slender....................................................................................... .. 14

14 Anterior setiform process longer than the claw................................................. M. queenslandica

- Anterior setiform process equal to or shorter than the claw................................................... 15

15 Anterior setiform process 1/2 the length of the claw............................................ M. konkakinhensis

- Anterior setiform process as long as the claw................................................... M. dongnaiensis