Tethysimyia litophila Ebejer 2023, sp. nov.
Creators: name: Ebejer, Martin J.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Diptera
Chyromyidae
Tethysimyia
Tethysimyia litophila

description: Tethysimyia litophila sp. nov.
Figs 13–14
Material: holotype ♁, MEXICO: Chiapas, Puerto Arista, - v.1985, leg. A. Freidberg, (SMNHTAU–419095). Paratypes: 1♁, 2♀♀, (male headless, dissected), same data and depository as holotype.; 1♁, (abdomen dissected), COSTA RICA: Puntarenas, viii.1980, leg. N.L.H. Krauss (UZMC).
Diagnosis: A small species that has ocular microtrichia, pale brown vittae on the scutum, shiny, broad dark brown bands on the abdominal tergite with large round spots on tergite 6 in both sexes. The aedeagus has a broad basiphallus and a relatively short distiphallus compared to congeners.
Description
Male.
Head: all yellow, ocelli reddish brown; frons at vertex about 0.5 width of head, narrowed anteriorly, at level of antennae 0.7 width that at level of anterior ocellus; frons inflated and produced anteriorly above and beyond eye; about 36 pale proclinate setulae scattered on frons; gena narrow in front, deeper behind, in profile, below middle of eye, about 0.8 height of eye, with several, scattered, glistening, pale yellow setulae; occiput in profile narrowly visible behind eye, postocular setulae short, in one row, eye with scattered microtrichia; mouth parts all yellow; 3 short vibrissal setulae about half length of orbital; face short, poorly sclerotized and depressed; median carina developed; antenna yellow, pedicel with distinct short seta dorsally; basal flagellomere with fine pubescence along anterior margin; first segment of arista yellow, second brown; chaetotaxy: 2 short fronto-orbitals, 1 inner and 1 outer vertical, both moderately developed; ocellars broken in holotype, but long and divergent in paratypes, 1 minute divergent pair of postocellars, paraverticals absent; about 36 (50 in females) short pale setulae scattered on frons.
Thorax: pale yellow; scutum with brown patch on lower anterior declivity and 4 broad deeper yellow to pale brown vittae on dorsum; chaetotaxy: 1 postpronotal, 1 presutural intraalar, 2 notopleurals, 2 dorsocentrals, anterior about half length of posterior, 1 postalar, 1 short intrapostalar, acrostichals in 6–8 rows, prescutellars 2 pairs in transverse row, 4 scutellars, 1 anepisternal at middle of posterior margin, 1 katepisternal at upper posterior corner. Some paratypes have a few minute setulae below katepisternal seta.
Wing: veins all pale yellow; distance on costa between R 2+3 and R 4+5 about 0.5 that between R 4+5 and M; distance between cross veins about 2.2 length of posterior cross vein, which lies slightly oblique and is about 0.3 length of apical section of vein Cu. Haltere pale yellow.
Legs: not modified except for pectinate-like setae on ventral surface of mid basitarsomere; numerous pale setulae scattered on all pairs of legs, apico-ventral seta on mid tibia strong; claws black in apical 2/3; hind trochanter not modified.
Abdomen: tergites yellow with subshining dark brown transverse bands dorsally; very few and fine pale setulae except along posterior margins of tergites.
Hypopygium: (Fig.14), epandrium small and pale, bearing a surstylar lobe; cerci small and pale; hypandrium distinct, long and narrow bearing a setulose pregonite posteriorly; phallapodeme long rod-like, postgonites short, apically spatulate and curved dorsomedially; distiphallus pale, weakly sclerotized and narrow apical section longer than broad basal section.
Female: (Fig. 13D), differs from male in having a more setulose frons; dorsal vittae more pronounced, being pale brown; abdomen with tergites having narrower brown transverse bands with a triangular extension posteriorly in the midline and the 6 th tergite with a pair of round brown spots leaving the middle clear yellow.
Body length: male 1.2mm, female 1.4mm, Wing length: male 1.0mm, female 1.4mm.
Etymology: the species epithet is a combination of the Latin: litus = coast and the Greek φιλία = friendship (in zoological nomenclature this is taken as affinity or a liking for) refers to the habitat of this species.
Similar species: each of the three species described from the Galapagos has one or more structures similar to the new species. The aedeagus of T. arenicolum (Wheeler & Sinclair 1994: 443, figs 1–6) is similar, but the pregonite is much larger and longer, the postgonite narrower and shorter; T. litophila differs from T. galamarillum (Wheeler & Sinclair 1994: 446, figs 7–10) in having a smaller epandrium and proportionately longer hypandrium and phallapodeme; from T. rabida (Wheeler & Sinclair 1994: 448, figs 11–14) it differs in the shapes of the gonites, phallapodeme and hypandrium.
Distribution: Pacific coast of Costa Rica and Mexico.
description: Published as part of Ebejer, Martin J., 2023, A first account of Chyromyidae (Diptera: Acalyptratae) from continental Central and South America and some Caribbean Islands, with descriptions of new species, pp. 301-331 in Zootaxa 5319 (3) on pages 321-322, DOI: 10.11646/zootaxa.5319.3.1, http://zenodo.org/record/8202839