Heteropodalebar sp. nov.: a new species from the highlands in Pahang State, Malaysia (Sparassidae, Heteropodinae) with a distinct sexual colour dimorphism

Abstract Background The genus Heteropoda Latreille, 1804, is ranked as the second within the family Sparassidae Bertkau, 1872. Up to now, sixteen species of this genus have been described from Malaysia. New information A new species of this genus in the highlands of Pahang State, Malaysia is described under the name of H.lebar sp. nov.. Individuals of the new species live in primary forests on forest floor, active in the night on the leaf litter.

New material recorded from Pahang State, Malaysia, revealed a species new to science with a distinct sexual colour dimorphism.It is diagnosed, described and illustrated and a distribution map is provided.

Materials and methods
All spiders are preserved in 70% denatured ethanol.Observations and drawings were made using a Leica MZ 16 stereomicroscope and a Leica DLMS compound microscope, each with a camera lucida attachment.Photographs of live and preserved specimens were taken with a Canon EOS R and a Canon 100 mm macro lens in combination with a Canon MR 14EX ringlite.Photographs of copulatory organs were taken with a Leica DMC4500 digital camera attached to a Leica M205 C digital microscope.
Prosoma length/width is the length/width of the dorsal shield of the prosoma, opisthosoma length/width is the length excluding petiolus and spinnerets.Eye distances were measured in orthogonal views.Leg formula, leg spination pattern and size classes follow Jäger (2001).Palp and leg lengths are given as: total (femur, patella, tibia, metatarsus, tarsus).The arising points of appendages of the male bulb are given in clock-position of the left palp in ventral view.Colouration is described from specimens in ethanol and live specimens.All measurements are given in millimetres.Data in square brackets were retrieved subsequently.Elevation of localities are given in metres (m).The map was produced using ArcMap version 10.8.1.
Copulatory organ (Fig. 2).As in diagnosis.Epigynal field only slightly wider than long, anterior bands distinct, fused, with one slit sensillum on each side close to field.Median septum distinctly longer than wide, with anterior part narrow, septal pocket distinctly developed.First winding wide, ventro-laterad; glandular appendages connected with posterior part by an S-shaped duct, visible in ventral view; posterior part of internal duct system consisting of various bulged parts; fertilisation ducts postero-ventrad.
Colouration (Fig. 5c-d).As in male, but generally darker.DS with dense cover of dark setae, light patches visible through this cover.Legs dorsally uniformly covered with dark setae.OS almost uniformly brown, dorsally darker with dense cover of dark setae and light patches, the latter larger in anterior and smaller in posterior half.Live spiders almost uniformly dark brown to black with iridescent purplish shimmer on femora; DS with typical light, almost white crescent submarginally on posterior and with many small light spots on legs and OS (Fig. 6b).

Diagnosis
The situated at lateral margin of first winding, 3. Posterior part of internal duct system wider than long.

Etymology
The specific name is derived from the Malay word lebarmeaning broad ) ‫ل‬ ‫ي‬ ‫ب‬ ‫ا‬ ‫ر‬ ( , referring to the fact that the males with a widened conductor; adjective.

Biology
Spiders were observed during the night on the forest floor on the leaf litter of secondary or primary forests in elevations between 1000 and 1300 metres.Only in two females scars were found (one irregular elongated scar on left patella IV dorsally; one small round scar on right coxa III proximo-ventrally).It might be that mating bites do not often occur in this species.

Discussion
This new species was previously identified as H. tetrica Thorell, 1897 (Thorell 1897) on the social network iNaturalist (https://www.inaturalist.org/home),especially the dark coloured females.Although there is a superficial resemblance of both species in having a strong sexual colour dimorphism with dark and more uniformly coloured females and lighter and vividly patterned males, there are distinct differences when looking in detail discerning both species even by interpreting photographs.H. lebar sp.nov.males have femoral spine patches fused in all legs (Fig. 6a), whereas these are separated at least in legs I-II in H. tetrica (Fig. 6c).Moreover, the dark pattern on the dorsal prosoma is more strongly developed in H. lebar sp.nov.(Fig. 6a), i.e. the large patches in the thoracic part reaching closer to the margin and are connected with marginal patches (vs.thoracic patches distinctly separated from margin in H. tetrica, Fig. 6c).Females of H. lebar sp.nov.have a uniformly dark colouration (Fig. 6b) with small light dots on opisthosoma and femora (vs. a variable, but generally lighter colour without such light dots in H. tetrica, Fig. 6d).However, for an unambiguous identification, dissection of the genitalia is recommended.The internal duct system of females of H. lebar sp.nov.does not show any widened parts that could be easily discerned as spermathecae as, shown schematically for Theridion melanurum Hahn, 1831 (Hahn 1831) and naturalistically for Cupiennius salei (Keyserling, 1877) (Keyserling 1877) (Foelix (2011): figs. 7.13a-b;Wiehle (1937): fig. 117 [sub T. denticulatum Walckenaer, 1805], 1967: fig. 29) (Walckenaer 1805, Wiehle 1937, Wiehle 1967, Foelix 2011).This scheme is widely used as the blueprint for female copulatory organs.Although schematically correct, this shape is rarely seen in the majority of spiders.Instead, there is rather a duct system as shown in Järvi (1912) and Järvi 1914 for Sparassidae (Bertkau 1872) that may or may not have any widened parts.In many Heteropoda species, these ducts of similar width are coiled and subsequently fused by sclerotisation of the surface of a spherical structure as shown, for example, in Jäger (2008: figs. 88, 92-93, 96, H. hirsti Jäger, 2008) (Jäger 2008).In this case, the ducts are kept as such.In other cases, the coiled ducts may fuse and build a secondarily widened receptacle (as in H. christae, Jäger, 2008: figs. 195, 197, 203) (Jäger 2008).In H. lebar sp.nov., the stage of coiled ducts without fusion of the surface known from subadults (e.g. in H. homstu Jäger, 2008: fig. 271) (Jäger 2008) is apparently retained in the adult stage.That brings up the question of what can be called "spermathecae" in such a duct system.By definition, it should be the part in which sperm is deposited and maintained until being used for fertilising the eggs.As there is no morphological evidence of such a functional part, we avoid this (functional) term here.It might well be that, in all parts of the duct system behind the glandular pores, sperm is deposited as suggested by Jäger (2006: 60) (Jäger 2006).However, this needs to be confirmed through mating experiments, during which the specimens are frozen while copulating.
males of H. lebar sp.nov.canbedistinguishedfromthose of all other congeners by the widened apical part of the conductor with retrolaterad, acuminate, triangular and rounded part (Figs1, 4a-c).Females of H. lebar sp.nov.resembleH.aemulans Bayer &Jäger, 2009 (Bayer and Jäger 2009) by the shape of median septum in ventral view, but can be recognised by the following combination of characters (Figs 2, 3, 4d-e): 1. Width of anterior part of median septum one fifth of maximal width of median to posterior part, 2. Glandular appendages elongate, small rounded in ventral view, H. tetrica Thorell, 1897, male from Vang Vieng, Vientiane Province, Laos; d: H. tetrica Thorell, 1897, female from Thakek, Kkammouane Province, Laos.