DOI: 10.5061/dryad.j3tx95xn9
title: Length-mass allometries of larval mosquitoes and aquatic dipterans: differences between taxa, traits and methods

description: Body mass underpins many ecological processes at the level of individuals,
 populations and communities. Often estimated in arthropods from linear
 traits such as body length or head width, these relationships can vary
 even between closely related taxa. Length-mass relationships of mosquito
 (Diptera: Culicidae) larvae are poorly known, despite the importance of
 this taxon to disease and aquatic ecology. To fill this gap, we measured
 ontogenetic changes in linear traits (body length, head width and thorax
 width) and dry and wet masses, and estimated length- and width-mass
 relationships in larvae of three Culicidae species inhabiting different
 niches: the tropical Aedes albopictus (Skuse, 1894), the temperate Culex
 pipiens (Linnaeus, 1758) and the snowmelt Ochlerotatus punctor (Kirby,
 1837). We compared these data with published length-weight allometries of
 other larval aquatic dipterans. We show that thorax width and body length,
 but not head width, reliably predict body mass for the three mosquito
 species. The length-mass allometry slopes in aquatic dipterans vary
 considerably between and within families but are independent of phylogeny,
 specimen handling, preservation techniques, and data fitting method.
 However, slope estimates become less precise with decreasing sample size
 and size range. To obtain reliable estimates of the allometric slopes, we
 recommend using data on all larval stages for intraspecific allometries
 and a wide range of species for interspecific allometries. We also caution
 against indiscriminately using of length-mass allometries obtained for
 other taxa or collected at lower taxonomic resolution, e.g. when using
 length-mass relationships to estimate biomass production at a given
 site. 
description: <em>Aedes albopictus </em>and <em>C.
 pipiens</em> were raised in the laboratory. The eggs, from
 laboratory, were immediately placed in aged tap-water at 20°C upon
 delivery. After hatching, larvae of each species were kept together in 10
 L containers in temperature-controlled rooms (18L:6D photoperiod) at ca.
 25°C, and fed three times a week with Brewer's yeast
 <em>Saccharomyces cerevisiae</em> at ca 100
 mg.L<sup>-1</sup>. <em>Ochlerotatus punctor</em>
 larvae were collected in a swamp in the Czech Republic and maintained in
 10 L plastic containers in thermal cabinets at 6°C (mean ± SD = 6.1 ± 0.2
 °C) with 9L:15D photoperiod and fed with grounded Brewer's
 yeast. We measured the total body length
 (<em>TL</em>;<em> </em>from the tip of the head to
 the base of the siphon), maximum thorax width
 (<em>TW</em>)<em> </em>and head width across eyes
 (<em>HW</em>) of each individual with QuickPhoto 3.1 software
 (Promicra, Czech Republic) from pictures taken with an Infinity1 camera
 (Lumenera, Canada) mounted on an Olympus SZX10 stereomicroscope. Each
 individual was then gently blotted on a slightly wetted paper towel to
 remove excess water and immediately weighted in a pre-dried and
 pre-weighted aluminium cup on the MSA6.6S-0CE-DM micro-balance (Sartorius,
 Germany) to determine the wet mass <em>W</em> to the nearest
 0.001 mg. Afterwards, the individuals were oven-dried at 50°C for 24 h
 following (Benke and Huryn 2006) and weighed again using the same
 micro-balance to determine the dry mass
 (<em>DW</em>).
description: # Length-mass allometries of larval mosquitoes and aquatic dipterans:
 differences between taxa, traits and methods
 The table provides the
 measures mosquitoes used in our analysis to determine the length-mass
 allometries. ## Description of the data and file structure The table
 provides the measures of the total body length (from the tip of the head
 to the base of the siphon), the maximum thorax width, the head width
 across eyes (all in mm), and the wet and dry masses (in mg) of three
 Culicidae species: *Culex pipiens* (CULX), *Aedes albopictus* (AEDS) and
 *Ochlerotatus punctor* (OCHL), measured at consecutives larval stages.
 Individual ID formatted as : species-individual number-date of arrival in
 the lab. Some additional *Aedes* from the same batches and raised in the
 same conditions as the other larvae were measured to increase the number
 of data, and are noted *AEDS-SuppXXX*