Paleotelmatoscopus Curler & Skibińska, 2021

Curler, Gregory R. & Skibińska, Kornelia, 2021, Paleotelmatoscopus, a proposed new genus for some fossil moth flies (Diptera Psychodidae, Psychodinae) in Eocene Baltic amber, with description of a new species, Zootaxa 4927 (4), pp. 505-524 : 507-508

Paleotelmatoscopus Curler & Skibińska gen. nov.

urn:lsid:zoobank.org:act:D1F98CEE-808E-4DFB-A291-AE3E6A357568

Type species: Pericoma formosa Meunier, 1905 , by present designation.

Diagnosis. Only known from Eocene Baltic amber (34–48 Mya; Seyfullah et al. 2018). Antenna ( Figs. 7 ; 17 ) with the following combination of character states: Scape elongate, at least three times longer than wide; male pedicel with basal half cylindrical, apical half globular; male flagellomere 1 fusiform to globular, always clearly differing in shape from remaining flagellomeres; flagellomeres 2–13 nodiform, symmetrical; flagellomere 14 acorn-shaped, with subapical digitiform process; flagellomeres 2–13 (unknown for f14) with two ascoids, inserted on node opposite each other; ascoids ( Figs. 10 ; 13 ) fan-like, each with 4–6 separate, digitiform branches in male, 3 branches in female. Gonocoxite (in dorsal view) with flat, quadrate extension basomedially ( Figs. 4 ; 14 ; 18 ; 21 ).

Species included:

Paleotelmatoscopus formosa ( Meunier, 1905)

Paleotelmatoscopus madrizi sp. nov.

Comments. Characterizing Paleotelmatoscopus as a genus is somewhat precarious due to its similarity to several extant genera (e.g. Telmatoscopus Eaton, 1904 ; Seoda Enderlein, 1935 ; Jungiella Vaillant, 1972 ). Many diagnostic characters that are described for extant psychodine genera are of the internal male genitalia. Characters of the male genitalia, some of which were discussed by Kvifte (2014), are of paramount importance for separating genera and species; however, in fossil taxa this is limited to external characters such as the length and curvature of gonostyli and surstyli, or the number of tenacula. So far, these have proven to be less useful for separating species of Paleotelmatoscopus , as their male genitalia, on the exterior, are more uniform.

The most reliable male genitalia character for distinguishing Paleotelmatoscopus from related genera is the dorsal part of the base of the gonocoxite. In Paleotelmatoscopus it is broad, quadrate and dorsoventrally compressed ( Fig. 14 ), with gonocoxites clearly separate. In Telmatoscopus , it is narrowed to a point and the gonocoxites meet at the median line ( Vaillant 1989, Fig. 2 ; Kvifte 2014, Fig. 1C ), while in Seoda it is rounded, with gonocoxites clearly separated ( Ježek 1989, Fig. 13 ; Kvifte 2014, Fig. 2 C–D) and in Jungiella it is truncate, without an extension of the base ( Omelková & Ježek 2017, Figs. 14 ; 38). In contrast to the variability of the gonocoxites, the gonostyli of Paleotelmatoscopus and related genera are remarkably similar. Curvature of the gonostyli, with a distinctive, angular bend at midlength, are most similar to Telmatoscopus advena Eaton, 1893 ( Vaillant 1989, Figs. 2–3 ) and some species of Seoda ( Ježek 1989; Figs. 27–28 ; 35; 41).

Head capsules of Paleotelmatoscopus species observed in this study are typical of the form observed in related genera: rounded or slightly pyriform in frontal view; 4 facet rows in eye bridge, separated at median by distance of approximately two facet diameters; with corniculi in some species. The antennae appear to be the only character suite in the head capsule that can be used to separate genera. Most notably, flagellomeres in Paleotelmatoscopus are not strongly asymmetrical as in related genera, and their ascoids are palmate. Nonetheless, all specimens examined by us had incomplete antennae, missing one or more flagellomeres and ascoids; this prevented an accurate description of flagellomere 14 with regard to whether it bears ascoids. Diagnostic characters given above for the genus are based on a survey of all specimens available to us; however, this will require revision based on the study of additional material.

Wings of Paleotelmatoscopus are also similar to related genera, except some species of the fossil genus (e.g. P. formosa ) have a posterior wing margin that is comparatively more convex, with a CuA cell that is expanded posteriorly. Paleotelmatoscopus can be readily distinguished from Telmatoscopus because species of the former have the apex of R 5 terminating posterior to the wing apex, while the latter have the apex of R 5 terminating at the wing apex; however, separation of the new genus from other related genera requires greater scrutiny.

Female Paleotelmatoscopus do not appear to have distinctive genus level characters. Association of males and females thus far is mainly based on specimens that are syninclusions.

Figures

FIGURES 7–12. Photomicrographs of Paleotelmatoscopus formosa (Meunier, 1905) specimens. 7. Male, frontal and partial ventral view [MP/3960/1]. 8. Male head and prothorax, frontolateral view [CCHH 1800-2]. 9. Male, frontolateral and partial ventral view [LACM 340459]. 10. Male head, frontal view [MZ 15165]. 11. Female, frontolateral view [MZ 13195]. 12. Male head and thorax, frontolateral view [CCHH 69-12]. Abbreviations: asc = ascoid; crn = corniculum; f1 = flagellomere 1; f2 = flagellomere 2; ped = pedicel; scp = scape. Scale bars: 0.20mm (Figs. 7, 9, 11); 0.50mm (Figs. 8, 10, 12).

FIGURES 15–20. Photomicrographs of Paleotelmatoscopus madrizi Curler and Skibińska sp. nov. specimens. 15. Holotype male, frontolateral view [CCHH 1800-3]. 16. Holotype male, posterolateral view [CCHH 1800-3]. 17. Paratype male, frontolateral view [CCHH 914-1]. 18. Paratype male, dorsolateral view [CCHH 914-1]. 19. Paratype male, frontal view [MZ 14841]. 20. Paratype male, lateral view [MZ 17279].Abbreviations: f1 = flagellomere 1; f2 = flagellomere 2; ped = pedicel; scp = scape. Scale bars: 0.50mm

FIGURES 13–14. Interpretive line drawings of Paleotelmatoscopus madrizi Curler and Skibińska sp. nov. 13. Holotype male, frontolateral view [CCHH 1800-3]. 14. Paratype male terminalia, dorsolateral view [CCHH 911-1]. Abbreviations:A1 = first anal vein; asc = ascoid; crn = corniculum; Cu =cubital vein;epd = epandrium; f1 = flagellomere 1; f2 = flagellomere 2; gcx = gonocoxite; gst = gonostylus; hpd = hypandrium; hpr = hypoproct; M1 = first branch of media; M2 = second branch of media; M3 = third branch of media;M4 = fourth branch of media; Mfk = medial fork;ped = pedicel; prm = paramere; R1 = anterior branch of radius; R2 = upper branch of second branch of radius; R3 = lower branch of second branch of radius; R4 = upper branch of third branch of radius; R 5 = lower branch of third branch of radius; Rfk = radial fork; Sc, subcostal vein; scp = scape; sur = surstylus; ten = tenacula.

FIGURES 3–6. Photomicrographs of Paleotelmatoscopus formosa (Meunier, 1905) specimens. 3. Male, frontal and partial ventral view [CCHH 1800-1]. 4. Male, caudal and partial dorsal view [CCHH 1800-1]. 5. Male, frontolateral view [CCHH 1800-2]. 6. Male, frontolateral view [MP/3960/2]. Abbreviation: crn = corniculum. Scale bars: 0.50mm

FIGURES 21–24. Photomicrographs of Paleotelmatoscopus madrizi Curler and Skibińska sp. nov. specimens. 21. Paratype male, dorsal view [CCHH 911-1]. 22. Paratype female, lateral view [CCHH 499-1]. 23. Paratype female, lateral view [MZ 13274]. 24. Paratype female, lateral view [MZ 19042]. Scale bars: 0.50mm

FIGURES 1–2. Photomicrographs of Paleotelmatoscopus formosa (Meunier, 1905) lectotype male [Z2681/GZG BST 6169]. 1. Whole specimen, frontal view. 2. Head, frontal view. Abbreviation: crn = corniculum. Scale bars: 0.25mm

FIGURES 26–28. Photomicrographs of 26. Pericoma speciosa Meunier, 1905, male, frontal view [MZ 17325]. 27. Female, lateral view [LACM 340462]. 28. Male abdomen and left wing, dorsal view [MZ 17325]. Scale bars: 0.50mm