Sciophila holopaineni Salmela

Dataset
New and poorly known Palaearctic fungus gnats (Diptera, Sciaroidea): Rank
SPECIES: Published in
Salmela J, Kolcsár L (2017) New and poorly known Palaearctic fungus gnats (Diptera, Sciaroidea). Biodiversity Data Journal 5: e11760. https://doi.org/10.3897/BDJ.5.e11760

Classification

kingdom
Animalia: phylum
Arthropoda: class
Insecta: order
Diptera: family
Mycetophilidae: genus
Sciophila: species
Sciophila holopaineni

Description

Male. Head black. Ocelli arranged in a row, on the posterior part of vertex; ratio of distance of lateral ocellus from median ocellus: distance of lateral ocelli from eye = 0.52. Vertex, anterior part of face and clypeus covered by dark setae. Eyes pubescent. Palpi infuscated, with dark setae. Length ratio of palpal segments 3–5: 3:4=0.94, 4:5=0.43. Penultimate segment 3.4 times as long as wide, last segment 9.3 times as long as wide. Antennae 16-segmented (scape, pedicel and 14 flagellomeres), black. Scape:pedicel length ratio 1.30; scape with a rounded, a bit depressed sensory field in its lateral base, having 7 minute setae. Flagellomeres cylindrical, length:width ratio of 1st flagellomere 1.51, 4th flagellomere 1.76 and apical flagellomere 3.13. Flagellomeres covered by dense light setosity, setae slightly curved, their length shorter than width of respective flagellomere; polygon-like (reticulate) pattern present, especially so in apical flagellomeres.

Thorax black. Scutum covered by pale setae. Anepimeron bare, other sclerites setose. Scutellum with eight setae in a curved row. Halteres light brown with pale setae; apical part of stem and base of knob infuscated.

Wings hyaline, lamina covered by both macro and microtrichia. Base of Rs, R4 and r-m bare, other veins setose, veins light brown to dark brown. C exceeding tip of R5 25 % of the distance between R5 and M1. Sc2 situated between base of Rs and R4. Furcation point of median fork at the level of bRs. M1+M2 very short. Length ratio of M1+2:r-m = 0.53. Wing length 3.2 mm.

Fore coxae light brown, mid and hind coxae dark brown, with pale setae, trochanters dark-brown. Legs yellowish brown, femora basoventrally darkened; apices of mid and hind coxae infuscated, the latter more clearly so. Setae on femora mostly dark, tibial and tarsal setae dark. Length ratio of femur to tibia for fore, mid and hind legs: 0.93, 1.03, 0.89. Length ratio of tibia to basitarsus for fore, mid and hind legs: 1.36, 1.57, 1.89. Anteroapical depressed area of the fore tibia with two rows of pale setae, proximal row curved with ca. 17 setae and distal row almost straight with ca. 20 setae. Ratio of apical width of tibia:length of longest tibial spur for fore, mid and hind legs: 0.52, 0.33, 0.33.

Abdominal tergites and sternites dark brown - almost black, covered by dark setae. Distal margin of 9th tergite rounded (Fig. 4a). Gonocoxal apodemes shallow Y-shaped; apex of mesial branch rounded, and apex of proximal branch weakly pointed (Fig. 4b). Large median appendage of gonostylus with ca. 19 comb-like megasetae (Fig. 4d). Small median appendage of gonostylus with two or rarely three long setae (Fig. 4e). Ventral lobe of gonostylus with a highly prominent, elongated outgrowth; basally with two long setae (Fig. 4c, d, e). Aedeagus apically blunt, about as long as parameres. Parameres rather thin, apices contorted (Fig. 4b, f).

Diagnosis

This is a very dark species with the head, antennae, thorax, and abdomen black or dark brown. The 9th tergite is apically rounded. The ventral lobe of the gonostylus has a prominent apical outgrowth. The aedeagus is about as long as the parameres with the apex truncated. The parameres are rather thin with their apices contorted.

Etimology

The new species is named after Mr. Tuomas Holopainen, the founder, songwriter and keyboardist of a Finnish metal band, "Nightwish". The name is a genitive.

Ecology

The type locality in Törmäoja Conservation Area was a sloping birch forest in a river canyon, close to a spring brook.

Distribution

The new species is so far known only from eastern Finnish Lapland, the north boreal ecoregion (Fig. 5).

Discussion

The new species seems to be rather distant from the known Holarctic species of Sciophila. The number of large setae on the small median appendage of gonostylus is varying, it may be two or three, thus making the use of Zaitzev's (Zaitzev 1982) key problematic. If two setae, the new species comes closest to S. impar Johannsen, a species that shares some traits with the new species (e.g. smoothly rounded distal edge of 9th tergite, aedeagus with a blunt apex), but is otherwise very different, having e.g. a high number of comb-like megasetae on the large median lobe of the gonostylus (63–65 vs. 19 in S. holopaineni sp.n.). If three setae, the species runs to the couplet 79 and thereafter to 95, 99, 109 and finally to 114, but the new species does not fit either S. kashmirensis Zaitzev or S. stackelbergi Zaitzev. Holotype male had two and three setae, paratype male had two in both gonostyli.

We were not able to find any notes in the literature on the presence of a sensory field at the base of scape among Sciophila. JS checked a few specimens in his collection (JES), and the character was present in S. buxtoni Freeman, S. curvata sp.n., Leptomorphus forcipatus Landrock, Polylepta borealis Lundström and Allocotocera pulchella (Curtis), but it was absent among Anaclileia dziedzickii (Landrock). In Acnemia trifida Zaitzev there was an ventroapical sensory field at the scape, with hyaline cover. It is possible, that this trait is symplesiomorphic (an ancestral character or trait state shared by two or more taxa) amongst Sciophilinae and is lost in some genera.

Name

Homonyms: Sciophila holopaineni Salmela