Neotropical Nilothauma Kieffer, 1921 (Diptera, Chironomidae): Key, eleven new species, re-descriptions, new combination and new records Author Pinho, Luiz Carlos https://orcid.org/0000-0002-9153-9997 Laboratory of Systematics of Diptera, Department of Ecology and Zoology, Federal University of Santa Catarina, Campus Trindade, CEP 88040 - 900, Florianopolis, Brazil luizcarlospinho@gmail.com Author Andersen, Trond Department of Natural History, University Museum of Bergen, University of Bergen, P. O. Box 7800, NO- 5020, Bergen, Norway text ZooKeys 2021 2021-04-22 1033 81 125 http://dx.doi.org/10.3897/zookeys.1033.60686 journal article http://dx.doi.org/10.3897/zookeys.1033.60686 1313-2970-1033-81 BEFB015F4A354987AD10DFEB7D4F91DD 2E6467D3D0025F778A77798A4072BCB5 Nilothauma maya sp. nov. Figures 10A, B , 16B Type material. Holotype male, slide-mounted: Mexico, Campeche, Calacmul, Ejido Nuevo Becan, El Chorro, 18°35'26"N , 89°15'29"W , 130 m a.s.l., 30.iv.1997, light trap, A. Contreras-Ramos et al. leg. (ZMBN). Etymology. Named after the Maya people, who used to live in the area. The name is to be regarded as a noun in apposition. Diagnostic characters. The male can be distinguished from its congeners by the combination of: pale brown species; wing without markings; tergite IX without setose dorsal lobe(s) or spine; anal point spatulate; superior volsella slender, curved, tapering; gonostylus curved, with strong setae on protruberance on inner margin in basal one-third. Figure 10. Nilothauma maya sp. nov. adult male A hypopygium, dorsal view B hypopygium with anal point and tergite IX removed, dorsal aspect to the left and ventral aspect to the right. Description. Male imago (n = 1). Total length 2.43 mm. Wing length 1.12 mm. Total length/wing length 2.17. Wing length/length of profemur 2.15. Colouration . Pale brown. Wing membrane without dark markings. Antenna . AR = 0.18. Thirteenth flagellomere 112 µm long. Head . Temporal setae 4 in single row. Clypeus with 13 setae. Tentorium and stipes not measurable. Palp segment lengths (in µm ): 21, 28, 65, 117, 144. Third palpomere with 2 sensilla clavata subapically, longest 19 µm long. Fifth palpomere/third palpomere 2.22. Thorax . Dorsocentrals 8 in single row, acrostichals 8, prealars 2. Scutellum with 2 setae. Wing . VR = 1.44. Brachiolum with 1 seta, R with 10 setae, R1 with 12 setae, R4+5 with 15 setae, remaining veins bare. Legs . Spur of fore tibia 48 µm long including 21 µm long scale. Mid-tibia with 1 spur, 26 µm long; hind tibia with 2 spurs, 25 and 33 µm long. Combs of mid-tibia 12 µm long, of hind tibia 17 µm long. Width at apex of fore tibia 36 µm , of mid-tibia 40 µm , of hind tibia 44 µm . Lengths and proportions of legs as in Table 9 . Table 9. Lengths (in μm ) and proportions of leg segments in Nilothauma maya sp. nov., adult male (n = 1).

-	Fe	Ti	ta1	ta2	ta3	ta4
p1	520	372	-	-	-	-
p2	484	308	208	76	56	32
p3	504	484	232	132	140	88
-	ta5	LR	BV	SV	BR	-
p1	-	-	-	-	-	-
p2	28	0.68	5.21	3.81	3.4	-
p3	48	0.48	2.99	4.26	4.7	-

Hypopygium (Fig. 10A, B ). Tergite IX without lobes, with 8 setae above anal point and 5 somewhat weaker setae to each side of anal point. Anal point spatulate, 36 µm long, maximum width 11 µm . Tergite bands continuous. Laterosternite IX with 2 setae. Phallapodeme 48 µm long; transverse sternapodeme 27 µm long. Gonocoxite 104 µm long. Inferior volsella curved, 55 µm long, 14 µm wide subapically, with microtrichia and 4 strong apical setae. Superior volsella slender, curved, tapering, 54 µm long, 11 µm wide at base, 3 µm wide subapically, covered with microtrichia and with 2 weak apical setae. Median volsella consisting of two small tubercles, about 4 µm long, each with single setae at apex, longest 15 µm long. Gonostylus 131 µm long, curved, with single, strong setae on protuberance on inner margin at 27 µm from base, setae 21 mm long. HR = 0.79. HV = 1.85. Female adult and immatures. Unknown. Remarks. The slide is distorted and the drawings are composites of left and right side. Distribution (Fig. 16B ). Only known from Campeche State in Mexico.