Checklist of the Collembola: Reproducing schematic habitus images of Sminthurides (Collembola) based on original colouration descriptions
http://www.collembola.org/publicat/schematc.htm - Last updated on 2020.02.27 by Frans Janssens
Checklist of the Collembola: Reproducing schematic habitus images of Sminthurides based on original colouration descriptions

Frans Janssens, Department of Biology, University of Antwerp, Antwerp, B-2020, Belgium

Abstract.
Reproducing schematic habitus images based on an algorithmic translation of original colouration descriptions.

Introduction

Note : the text is still in an embryological state...
To be completed.

Principle

The generated images are built up in a layered model.
From bottom to top:
3 levels:
Body background colour.
Body pigmentation pattern.
Body shape.
Each level can be built up in (semi)transparant layers.

Body background colour

A standard background colour description is required to be able to compare habitus descriptions of different species.
A colour has 3 parameters: colour(H,S,L)

H: hue or type of colour : 0-360 = visible spectrum
The primary colours are red (h=0), green (h=120) and blue (h=240).
The secondary colours are positioned inbetween two primary colours : red green = yellow (h=60), green blue = cyan (h=180), blue red = magenta (h=300).
Tertiary colours are positioned inbetween a primary colour and a secondary colour : red yellow = orange (h=30), yellow green (h=90), green cyan (h=150), cyan blue (h=210), blue magenta (h=270), magenta red = violet (h=330).

S: saturation or purity or intensity or chroma of the colour : 0-100%
0% = no colour
100% = pure colour

L: lightness or brightness of the colour : 0-100%
0% = absence of light = black
50% = normal light level
100% = maximum light level = white

Summary : any colour can be described as HSL(H,S,L)

Grey: The colours white and black are used to create respectively a light tint and/or a dark shade of any pure colour.
Mixing black (=HSL(any,0%,0%)) and white (=HSL(any,0%,100%)) results in grey (=HSL(any,0%,50%)).
Mixing black with a pure colour results in a (dark) shade of that colour HSL(H,100%,49-0%).
Mixing white with a pure colour results in a (light) tint of that colour HSL(H,100%,51-100%).
Mixing grey (=black+white) with a pure colour results in a tone of that colour.

Example of tones of colour "blue":
H = 240°
(Blue)
S%
L%
100
Pure colour
75
Bright
50
Pale
25
Dull
0
No colour
100 Maximum light          
87.5 Very light          
75 Medium light          
62.5 Slightly light          
50 Normal light          
37.5 Slightly dark          
25 Medium dark          
12.5 Very dark          
0 No light          
In the example we provide 9 levels of Lightness and 5 levels of Saturation.

Lightness:
Max light
Very light
Medium light
Slightly light
Normal light
Slightly dark
Medium dark
Very dark
No light

Saturation:
Pure colour
Bright colour
Pale colour
Dull colour
No colour

-ish as in yellowish

1. = having a less intense colouration of yellow : S=25-75%
2. = slightly yellow = slight degree of colouration of yellow : S=25-75%
S=0% = no colouration = grey.
S=100% = maximum colouration = pure colour.
We distinguish 3 levels of -ishness:
dull S = 25%
pale S = 50%
bright S = 75%

greyish blue = blue + less intense grey
blue = HSL(240,100%,50%)
grey = HSL(NA,0%,50%)
greyish = layer with opacity 0.5 of grey

Blue
2018.03.15 © Janssens, F.
Grey
2018.03.15 © Janssens, F.
Greyish blue
2018.03.15 © Janssens, F.

bluish grey = grey + less intense blue
grey = HSL NA,0%,50%
blue = HSL 240,100%,50%
bluish = layer with opacity 0.5 of blue
??? HSL 240,25%,50%

Grey
2018.03.15 © Janssens, F.
Blue
2018.03.15 © Janssens, F.
Bluish grey
2018.03.15 © Janssens, F.

Or:
greyish blue = s=75%
bluish grey = s=25% includes bluish white + bluish black
bluish white = s=25% + l=62.5%-87.5%
bluish black = s=25% + l=37.5%-12.5%
whitish blue = l=62.5%-87.5%
blackish blue = l=37.5%-12.5%
whitish grey = s=0% + l=62.5-87.5%
blackish grey = s=0% + l=37.5-12.5%
greyish white = s=0% + l=87.5%
greyish black = s=0% + l=12.5%

diffuse :
= adding another layer of colour with low opacity

The opacity of the white or black layer on top of the colour controles the level of paleness or darkness of the colour.
Examples:
"yellowish grey" = grey + white 0.8 + yellow 0.3
"diffuse violet pigment" = pale violet 0.3
"pale yellowish" = yellow + white 0.5
"pale violet brown" = brown + white 0.2 + paleviolet 0.3
"violet blue" =
"yellowish white" =
"dark blue" =
"pale yellow" =
"violet grey" =
"pale bluish violet" =

To be completed.

Regenerated Sminthurides female dorsal schematic colour patterns

Sminthurides aquaticus
Yellowish grey + diffuse violet pigment (Fjellberg 2007:178).
Layer 1 = grey = HSL NA,0%,50%
Layer 2 = yellowish = less intense yellow = HSL 60,100%,50% with opacity 0.5
Layer 3 = diffuse violet = HSL 330,100%,50% with opacity 0.2

Sminthurides aquaticus
sensu Fjellberg 2007:178
2018.03.15 © Janssens, F.



Light {yellowish grey + diffuse violet pigment} (Modified after Fjellberg 2007:178).
Layer 1 = light grey = HSL NA,0%,75%
Layer 2 = light yellowish = less intense light yellow = HSL 60,100%,75% with opacity 0.5
Layer 3 = diffuse light violet = HSL 330,100%,75% with opacity 0.2
Sminthurides aquaticus
sensu Janssens 2018
2018.03.15 © Janssens, F.

Sminthurides malmgreni
Pale yellowish + variable violet pigmentation : usually dark lateral band + dorsal spot, these may expand+fuse to cover most larger abdomen (Fjellberg 2007:179).

Sminthurides malmgreni
sensu Fjellberg 2007:179
2018.03.08 © Janssens, F.

Sminthurides malmgreni forma principalis Tullberg 1877
Body uniformly violet (Stach 1956:32).

Sminthurides malmgreni f. principalis
sensu Stach 1956:32
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma immaculatus Axelson 1905
Addomen yellow. Dark violet pigment forms only a band ventrolaterally on each side of great abdomen (Stach 1956:31).

Sminthurides malmgreni f. immaculatus
sensu Stach 1956:31
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma maculatus Agren 1903
Besides ventrolateral band, on dorsum a dark violet spot (Stach 1956:31).

Sminthurides malmgreni f. maculatus
sensu Stach 1956:31
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma abruptus Agren 1903
On dorsum two dark violet spots lying one behind the other, the anterior smaller and the posterior elongated; ventrolateral broad dark violet band (Stach 1956:31).

Sminthurides malmgreni f. abruptus
sensu Stach:1956:31
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma elegantulus Reuter 1883
Besides ventrolateral band, dorsally on great abdomen more or less longitudinal bands and patches (Stach 1956:32).

Sminthurides malmgreni f. elegantulus
sensu Stach 1956:32
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma quadrilineatus Agren 1903
On great abdomen four violet longitudinal bands, two ventrolateral and two submedian (Stach 1956:32).

Sminthurides malmgreni f. quadrilieatus
sensu Stach 1956:32
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma nigrescens Börner 1901
Darkly pigmented dorsum on which only more or less large spots remain laterally from the pale ground colour (Stach 1956:32).

Sminthurides malmgreni f. nigrescens
sensu Stach 1956:32
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma palustris Folsom & Mills 1938
Dark pigment weakly developed; only diffuse pigmentation ventrolaterally and dorsally on abdomen (Stach 1956:32).

Sminthurides malmgreni f. palustris
sensu Stach 1956:32
2018.03.09 © Janssens, F.

Sminthurides malmgreni forma dorsomaculatus Janssens & Picard 2018
Only dorsal violet spot. (Janssens 2018:il).

Sminthurides malmgreni f. dorsomaculatus
sensu Janssens & Picard 2018
2018.03.09 © Janssens, F.

Sminthurides parvulus
Pale bluish violet (Fjellberg 2007:185).

Sminthurides parvulus
sensu Fjellberg 2007:185
2018.03.08 © Janssens, F.

Sminthurides armatus
Violet blue (Fjellberg 2007:181).

Sminthurides armatus
sensu Fjellberg 2007:181
2018.03.08 © Janssens, F.

Sminthurides penicillifer
Pale yellowish + violet lateral band + dorsal spot, split in 2 bands in less pigmented specimens (Fjellberg 2007:178).

Sminthurides penicilifer
sensu Fjellberg 2007:178
2018.03.08 © Janssens, F.

Sminthurides signatus
Pale violet brown + 2 darker longitudinal dorsal bands (Fjellberg 2007:181).

Sminthurides signatus
sensu Fjellberg 2007:181
2018.03.08 © Janssens, F.

Sminthurides pseudassimilis
Violet grey (Fjellberg 2007:183).

Sminthurides pseudassimilis
sensu Fjellberg 2007:183
2018.03.08 © Janssens, F.

Sminthurides schoetti
Pale yellow + violet pigment on large abdomen leaving anterior midline + parts of sides unpigmented (Fjellberg 2007:183).

Sminthurides schoetti
sensu Fjellberg 2007:183
2018.03.08 © Janssens, F.

Sminthurides cruciatus
Yellowish white; abdomen darker + crosslike violet figure (Fjellberg 2007:182).

Sminthurides cruciatus
sensu Fjellberg 2007:182
2018.03.08 © Janssens, F.

Sminthurides annulicornis
Dark blue (Fjellberg 2007:183).

Sminthurides annulicornis
sensu Fjellberg 2007:183
2018.03.08 © Janssens, F.

Sminthurides sexoculatus
Violette, avec quelques petites taches claires ā l'avant (Betsch & Massoud 1970:213).

Sminthurides sexoculatus
sensu Betsch & Massoud 1970:213
2018.03.08 © Janssens, F.

To be completed.

References