Paramorganiella Tonnoir, 1929

Jaschhof, Mathias, Blank, Stephan M. & Kallweit, Uwe, 2010, Adult morphology of Paramorganiella adventurosa Tonnoir (Diptera: Mycetophilidae: Sciophilinae), including a description of the unique maxillary palpi, Zootaxa 2559 (1), pp. 36-46 : 37-40

Genus Paramorganiella Tonnoir, 1929

Tonnoir, 1929: 606, type species Paramorganiella adventurosa Tonnoir, 1929 , by monotypy.

Diagnosis. A typical Sciophilini of which the wing venation is diagnostic by combination of the following characters: Sc2 is present, situated beyond the origin of Rs; R4 is absent; the M-fork is incomplete due to the evanescent basal portion of M2; the CuA-fork is complete; and A2 is inconspicuously present ( Fig. 3C ). In addition, males are unmistakable by the strongly modified maxillary palpi ( Figs 2C–E , 4C ). A similar wing venation is found in the genera Morganiella Tonnoir & Edwards , Tasmanina Tonnoir , and an unnamed genus with one unnamed species from Tasmania (Jaschhof, unpublished), all with ordinary male palpi. In Morganiella , the M-fork is complete and the CuA-fork is incomplete due to the evanescent basal portion of CuA1 ( Tonnoir & Edwards 1927: plt. 62, fig. 74). In Tasmanina , both the M- and CuA-forks are complete, and Sc2 may be situated before or beyond the origin of Rs ( Tonnoir 1929: plt. 22, fig. 9; Jaschhof, pers. obs.). In the unnamed genus, the M-fork is complete and the CuA-fork is incomplete, as in Morganiella , but Sc2 is absent (present in Morganiella ), and r-m is short and oblique (long and longitudinal in Morganiella ).

Redescription. Color (freshly caught, ethanol preserved specimens). Male body dark brown, antennae bases and mouthparts pale. Legs pale, except hind coxa and basal and distal thirds of the hind femur, which are brown, as well as basal and distal ends of hind tibia ( Fig. 1A , see also Tonnoir 1929). Female body lighter brown, lateral portion of scutum, scutellum, laterotergite, and upper portion of mediotergite yellowish, abdominal segments bicolored, with yellowish hind margins. Brown regions of legs lighter than in males ( Fig. 1B ). Head. Head capsule in lateral view higher than long, with short setae, 6–7 postocular bristles at some distance from hind eye margin. Foramen situated above middle of head. Median convexity of postgena sclerotized. Frons setose. Frontal furrow incomplete, not reaching medial ocellus. Frontal tubercle blunttipped, setae on tubercle larger than setae on frons. Scape little longer and narrower than pedicel, both setose. 14 flagellomeres in male, 12 in female. Flagellomeres cylindrical, less than 2 times as long as wide, longer in male than in female, with very short stalks, nodes with short trichia, 1–2 short setae on flagellomeres 1–3 dorsally. 3 ocelli almost in line, situated frontally, medial ocellus slightly smaller than lateral ocelli which are several diameters from eye margins. Face finely setose, larger than clypeus, subrectangular, basal margin deeply notched ( Fig. 4C ). Proboscis longer than in many other Mycetophilidae due to elongate prementum ( Figs 1A–B , 2B–C ). Clypeus and maxillary palpus strongly modified in males ( Figs 2A–E , 4C ), almost unmodified from mycetophilid ground pattern in females ( Fig. 3A ), see P. adventurosa for details.

Thorax ( Fig. 5 ). Scutum with large lateral and dorsocentral setae, smaller setae elsewhere. Scutellum with 6 large setae in line, smaller setae elsewhere. Wing ( Fig. 3C ). Membrane on both sides with trichia in two sizes. Distal median plate setose. All veins with dorsal setae except for H, Sc2, Rs, and A2, ventral setae on Sc1, R1, R5, and R-M. Halter with stem and knob subequal in length, finely setose. Legs. Coxae with setae of various sizes. Femora with a few long setae subapically, fine short setae elsewhere. Tibiae with a few strong, stiff semi-erect setae about as long as tibial diameter, fine setae elsewhere. Tibial spurs 1:2:2, spurs on mid and hind tibiae unequal in length. Fore tibial organ with semicircular rim, numerous pale trichia. Ventral side of mid and hind tarsi with sparse strong semi-erect setae. All tibiae and tarsi with sparse, very fine erect setiform sensilla. Empodia almost as long as pretarsal claws. Claws small, slightly curved, without teeth. Male fore leg with specialized setae on fourth and fifth tarsomeres, together forming clamping apparatus ( Fig. 3B ), see P. adventurosa for details.

Preabdomen. All segments with large setae. Spiracles on segments 2–7. Sternites 2–6 in male and 2–7 in female with lateral foldlines. Terminalia. See P. adventurosa .

Remarks on morphology. Erect setiform sensilla, such as those present on the tibiae and tarsi of Paramorganiella adventurosa , have also been found in the genera Colonomyia Colless and Ohakunea Tonnoir & Edwards , which we regard as both unassigned to family (cf. Jaschhof & Jaschhof 2008b). These sensilla can easily be overlooked due to their small size and transparency (cf. Hippa & Jaschhof 2004: fig. 9, as “pale, blunt setae”). They appear to belong to the sciaroid ground plan and are more widespread among Sciaroidea and Mycetophilidae than is expressed in previous descriptive literature. The shape and position of the specialized setae on the male fore tarsus leave no doubt that this is a clamping apparatus for grasping or grabbing hold of something ( Fig. 3B , see Discussion). We are aware of similar tarsal modifications in other mycetophilid genera distantly related to Paramorganiella , such as Pseudobrachypeza Tuomikoski.

Systematic position. Tonnoir (1929) was certainly correct in suggesting a close relationship of Paramorganiella and Morganiella from New Zealand. Two other genera in Tasmania, Tasmanina and an unnamed genus (see above), belong obviously to this kinship. Morganiella and Tasmanina are not monotypic genera as supposed until now ( Matile 1989). In fact, Morganiella includes two, and Tasmanina six species (Jaschhof, unpublished). Apart from similarities in wing venation, all species of these genera share a similar outline of the male terminalia, in particular the slender gonostyli that are directed medially and gonocoxal apodemes that are variously equipped with processes and/or fringes. Both of these genitalic character states may be synapomorphies of a monophyletic Morganiella group, which will be discussed in detail once the unnamed species have been described. A taxonomic revision and detailed character analysis of this group of genera are in preparation.

Figures

FIGURE 1. Paramorganiella adventurosa Tonnoir. A: Male habitus. B: Female habitus.

FIGURE 2. Paramorganiella adventurosa Tonnoir, male. A: Clypeus, anterior view. B: Mouthparts, posterior view. C: Mouthparts, lateral view. D: Maxillary palpi, lateral view. E: Maxillary palpus, medial view. Scale 50 µm.

FIGURE 3. Paramorganiella adventurosa Tonnoir. A: Female mouthparts, anterior view. Scale 50 µm. B: Male fore tarsomeres 4–5, ventral view, arrows indicating the clamping apparatus. C: Male wing, dorsal view.

FIGURE 4. Paramorganiella adventurosa Tonnoir, male. A: Terminalia, tg 9 omitted, dorsal view. B: Terminalia, ventral view. C: Mouthparts, anterior view. Scale 100 µm.

FIGURE 5. Paramorganiella adventurosa Tonnoir, male. Thorax, lateral view. Scale 500 µm.