Ectaetia betzi, Amorim, Dalton de Souza & Brown, Brian V., 2020

Amorim, Dalton de Souza & Brown, Brian V., 2020, Urban Scatopsidae (Diptera) of Los Angeles, California, United States, Insect Systematics and Diversity 4 (1), No. 1, pp. 1-41: 4-6

publication ID 10.1093/isd/ixaa001

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Ectaetia betzi


Ectaetia betzi   sp.nov.

( Figs. 1 View Figs , 15 View Figs , and 28–30)

(Zoobank LSID: )

Diagnosis. Antenna with 10 flagellomeres. Proepimeron high, undivided, anterior spiracle on dorsal half of sclerite. Posterior tibia distally expanded, compressed. R 5 ending before mid of wing, running quite separate from C, strongly curved. CuP clearly present, setae on CuA and CuP. Aedeagus coiled, longer than body length.

Material Examined. Holotype ♂, United States, California, Riverside Co., Riverside , 33.984°N 117.313°W, BioSCAN site 47, 1–8 September 2016, Malaise trap, 375 m, Coll. Justin Betz, BioSCAN sample 18411 (on slide) ( LACM). GoogleMaps  

Description. Male ( Fig. 1 View Figs ). General body color dark brown. Body length, 2.38 mm. Head ( Fig. 28 View Figs ). Ovoid, higher than long; holoptic, eye-bridge large, about 8 facets wide; eye with small ommatotrichia, not densely setose; all ommatidia of similar size; three ocelli, lateral ocelli much larger than mid ocellus, separated from eye-bridge by more than their own width. Occiput with fine setae distributed irregularly on occiput, a sensillum midway between ventral margin and vertex; frons between eye-bridge and base of antennae bare; frontoclypeus short, with fine setae at dorsal half. Labella well-developed, setose. Maxillary palpus small, shorter than labella, slender, covered with scattered setae, with an apical sensory pit. Postmentum laterally compressed at base, with a pair of lateral arms widening towards apex. Antenna reaching about half of thorax; scape and pedicel short; 10 flagellomeres covered with scattered fine setulae, no sensilla; flagellomeres 1–9 wider than long, distal flagellomere club-shaped, about twice the length of previous flagellomere. Thorax ( Fig. 29 View Figs ). Scutum only slightly longer than wide; rather sparsely covered with fine setae, about 16 strong supra-alars. Antepronotum and proepimeron finely setose; spiracle on dorsal half of proepimeron, no separate spiracular sclerite, spiracle closer to anterior margin, setae restricted to area dorsal and posterior to spiracle. Anepisternum with fine setae along antero-dorsal margin,katepisternum with few setae on antero-dorsal corner. Mesepimeron with two setae on postero-dorsal area. Two setae on dorsal margin of meron, three fine subspiracular setulae; metepisternum well-developed, bare. Legs. Coxae brown, femora, trochanters brownish yellow, femora yellowish brown on basal half, particularly lighter on foreleg, brown on distal half; tibiae and tarsi brown, yellowish close to tip. Fore femur slightly bulging, hind tibia club-shaped, widening towards apex ( Fig. 31 View Figs ). No tibial spurs, hind tibia with a row of slightly elongate distal setae.Tarsi with first tarsomere about twice the length of second tarsome. Tarsal claws slender, curved, no teeth; empodium well-developed. Wing ( Fig. 30 View Figs ). Wing extending to beyond tip of abdomen, 1.40 mm long, 0.60 mm wide. All cells with microtrichia, no macrotrichia on wing membrane, dorsal macrotrichia on anterior veins, and on CuA and CuP. Wing length/h-R1 length, 2.9; WL/R 1 -R 5 length, 7.6; h-R5 length/WL, 0.45. Sc entirely absent, Hu hardly identifiable; first sector of Rs oblique, r-m absent, base of M 1 + 2 fused to R 5 (rmf) for a distance about twice the length of first sector of Rs; M 1, M 2, M 4 reaching wing margin, CuA and CuP not reaching margin; CuA gently curved towards posterior margin at proximal third. Haltere dark brown. Abdomen ( Fig. 15 View Figs ). Tergites dark brown, sternites brown. Tergite 3 and 4 more slender than tergites 2 and 5. Pretergite 2 present, bare. Sternite 1 not sclerotized, sternite 2 trapezoid, posterior margin much wider than anterior margin; sternites 3–8 wide. Sternite 8 wide and short, posterior margin clearly emarginated; spiracle 8 at membrane; tergite 8 about as long as wide. Terminalia ( Fig. 32 View Figs ). Gonocoxites short, widely separated, each gonocoxite with a pair of short digitiform inner distal projections, inner projection with some setulae distally, external margin distally only slightly produced beyond base of gonostyli; sternite 9 well-developed fused to gonocoxites, with a pair of ventral projections; gonostyli displaced medially, subquadrate, with few setulae distally; parameres long, flattened, extending well beyond distal margin of tergite 9; sperm pump attached to terminalia; aedeagus wide at base and a coiled extension longer than the body length; tergite 9 small, subquadrate, setose, placed quite distally dorsally in the terminalia. Cerci absent.

Female. Unknown.

Distribution. United States, southern California.

Etymology. This species is named after Justin Betz, citizen scientist participating in the BioSCAN project, responsible for trap in BioSCAN site 47, to whom we kindly acknowledge the effort and the dedication.

Remarks. Ectaetia   is not a particularly species-rich genus among the scatopsids. Two species of the genus have been recorded for the United States: E. clavipes Loew   , which has Holarctic distribution, and E. gracilis   McAtee—the type locality of this latter species is Washington, DC, but it is not recognizable based on the original description ( Cook 1963). Ectaetia betzi   can be clearly differentiated from E. clavipes   by the very short C and by the sclerites of the male terminalia ( Freeman 1985). One single male of this species was collected in site 47 (Riverside), in September 2016 during BioSCAN Phase II, at the extreme eastern range of the project.

The BOLDSystems website has 142 sequenced specimens of Ectaetia   gathering in four clusters, one of which with 134 specimens (http:// Ectaetia   [tax]).


Natural History Museum of Los Angeles County