Pseudosmittia Edwards, 1932

Ferrington Jr, Leonard C. & Saether, Ole A., 2011, A revision of the genera Pseudosmittia Edwards, 1932, Allocladius Kieffer, 1913, and Hydrosmittia gen. n. (Diptera: Chironomidae, Orthocladiinae) 2849, Zootaxa 2849 (1), pp. 1-314 : 141-144

Pseudosmittia Edwards

Pseudosmittia Goetghebuer, 1932: 126 (as subgenus of Smittia Holmgren, 1865 ), nomen nudum. A type species was not designated in the original work contrary to Article 13b of the Zoological Code.

Pseudosmittia Edwards, 1932: 141 . Edwards described the genus by inference (ICZN Article 13a (ii) and designated an eligible type species. Following ICZN Article 50a, Pseudosmittia must be credited to Edwards (1932).

Orthosmittia Goetghebuer in Goetghebuer & Lenz, 1943: 110 (as subgenus of Smittia Holmgren, 1869 ). Orthosmittia has mistakenly been synonymized with Smittia both by Freeman (1953: 208) and Saether (1981: 25). Syn. n.

Ancylocladius Sublette et Wirth, 1972: 5 . Syn. n.

Nikismittia nomen nudum ( Sasa, 1996a: 106; Sasa, 1998a: 42; Sasa 1998b, 113, Saether et al. 2000: 185; Yamamoto, 2004: 88). No type species has been designated as required by ICZN (1999 Article 13.3).

Not Hibarasmittia Sasa et Suzuki, 1998: 27, as subgenus of Pseudosmittia . Synonymized with Prosmittia Brundin, 1956 by Yamamoto (2004).

Not Diplosmittia Saether, 1981 sensu Saether et al. (2000: 185) , misidentification

Type species: Spaniotoma (Smittia) angusta Edwards, 1929 , by subsequent designation of Edwards (1932:141).

Other included species: Pseudosmittia aculeathrix sp. n.; P. acutilobata sp. n.; P. adunca Andersen, Saether et Mendes ; P. albipennis (Goetghebuer) ; P. amorimi Andersen, Saether et Mendes ; P. angusta (Edwards) ; P. brachydicrana (Edwards) ; P. brevifurcata (Edwards) ; P. cambuciensis Andersen, Saether et Mendes ; P. carioca Andersen, Saether et Mendes ; P. carita sp. n.; P. catarinense Andersen, Saether et Mendes ; P. christmasensis sp. n.; P. conjuncta (Edwards) ; P. cristagata sp. n.; P. cunealata sp. n.; P. dolabrata sp. n.; P. digitata Saether ; P. digitrienta sp. n.; P. danconai (Marcuzzi) ; P. dupla (Tokunaga) ; P. duplicata Caspers ; P. fusata sp. n.; P. fusivenosa (Tokunaga) ; P. gibbistyla Andersen, Saether et Mendes ; P. gracilis , P. guineensis , P. hirtella (Freeman) ; P. hirticaudatus sp. n.; P. holsata Thienemann et Strenzke ; P. insulsa (Johannsen) ; P. invirgata Andersen, Saether et Mendes ; P. joaqimvenancioi (Messias et Oliveira) ; P. kauaiensis (Hardy) ; P. kraussi (Tokunaga) ; P. lamasi Andersen, Saether et Mendes , P. lamellata Andersen, Saether et Mendes , P. laticauda sp. n.; P. legonensis sp. n.; P. licina sp. n.; P. littoralis (Tokunaga) ; P. longicornia sp. n.; P. macrobrachia (Edwards) ; P. magdae Andersen, Saether et Mendes ; P. malickyi sp. n.; P. mathildae , P. melanostola (Kieffer) ; P. nana Andersen, Saether et Mendes ; P. navama sp. n.; P. nishiharaensis Sasa et Hasegawa ; P. oahuensis (Hardy) ; P. palauensis (Tokunaga) ; P. palpina Andersen, Saether et Mendes ; P. paraconjuncta (Hardy) ; P. parifusata sp. n.; P. parinavama sp. n.; P. paulista Andersen, Saether et Mendes ; P. pedata sp. n.; P. pinhoi Andersen, Saether et Mendes ; P. propetropis sp. n.; P. pugnata sp. n.; P. remigula Saether ; P. reyei (Freeman) ; P. rostriformis Makarchenko et Makarchenko ; P. roquei Andersen, Saether et Mendes ; P. rotunda Caspers et Reiss ; P. setiforceps (Tokunaga) ; P. siamensis sp. n.; P. simplex Strenzke ; P. spinispinata sp. n.; P. tericristata sp. n.; P. tobaduovicesima Kikuchi et Sasa ; P. tokunagai sp. n.; P. topei Lehmann ; P. triangula (Tokunaga) ; P. trilobata (Edwards) ; P. tropis Andersen, Saether et Mendes ; P. umbonata Andersen, Saether et Mendes ; P. uncata Andersen, Saether et Mendes ; P. unniae sp. n.; P. windwardensis Saether ; P. xanthostola (Kieffer) ; P. yapensis (Tokunaga) ; P. zonata (Tokunaga) .

Diagnostic characters: The imagines are separable from other Orthocladiinae with bare eyes, wings and squama, by having 2 short, mostly biserial acrostichals on mid-scutum without additional tubercle, hump or microtrichial tuft; non-extended, non-protruding eyes; palp not reduced except in P. palpina Andersen, Saether et Mendes (although palpomeres 4 and 5 may be partly fused); costa not to moderately long extended; VR high to extremely high; Cu sinuate, curved or straight; wing often with additional vein caused by bifurcation of postcubitus; male anal point absent or placed forward on tergite IX with microtrichia reaching to apex; single, plate-like, median virga occasionally with additional pair of lateral rows of needle-like spinules or lateral lamellae; male gonostylus not double but occasionally furcate; female genitalia with gonocoxite IX long and low with characteristic sclerotized margin against tergite IX; small dorsomedian lobe; large ventrolateral lobe; and spermathecal duct with loop.

The pupae can be separated from other orthoclads by lacking a thoracic horn and a precorneal tubercle; having frontal setae usually present on frontal apotome; tergites II–VII with anterior and posterior spinules clearly larger than median spinules, resulting in a transversely striped appearance; usually conjunctives both dorsally and ventrally armed with spinules; anal lobe reduced or smoothly rounded without setae, or when these occasionally present no median seta and male genital sac without papilla.

The larvae are separable from all other orthoclads except Camptocladius v. d. Wulp, Allocladius Kieffer and Hydrosmittia gen. n. by having broad, bifid S I and S II, reduced antenna and no procerci. They differ from Camptocladius by having premandible with brush, and reduced to relatively well developed posterior parapods, usually with claws. From Allocladius and Hydrosmittia they differ by having the antennal blade extending beyond flagellum about 2–4 times as long as width of basal segment; and posterior parapods with 0–6 claws, except in P. mathildae with 8 claws, claws 0–18 µm long.

Description

Imago

Minute to medium sized species, wing length 0.5–2.7 mm. Coloration brown to black.

Eyes without dorsomedian elongation, bare. Male antenna with 13 flagellomeres except in some P. nana Andersen, Saether et Mendes with 12, occasionally division between terminal flagellomeres incomplete; fully plumed; antennal groove beginning on flagellomeres 3 to 4; sensillae chaeticae on flagellomeres 2, 3 and 13; apex rounded to pointed, bearing strong, subapical seta in P. albipennis , P. angusta , P. navama , P. parinavama , P. pugnata and some P. windwardensis only. Antennal ratio of male 0.15–2.1. Female antenna with 5 flagellomeres; 1 pair of broad sensilla chaeticae on each of flagellomeres 1–4; 1 broad pair, 0–1 relatively wide and about 20–30 slender, curved sensillae chaeticae on flagellomere 5, apical seta often present. Flagellomeres 2–4 fusiform, pyriform or nodiform. Antennal ratio of female 0.3–0.7.

Temporals uniserial; consisting of 0–10 isolated usually very weak inner verticals, absent only in P. pseudocostata and females of P. angusta , long only in P. cuneata ; 1–7 outer verticals; and 0–5, usually none, postorbitals normally not separated from outer verticals. Palp 5 segmented, third palpomere with 1–18 lanceolate to scalpellate sensilla chaetica, occasionally in a sensillum capitatum, or with a strong apical spine (in P. remigula and P. insulsa ) or a digitiform extension ( P. joaquimvencancoi ); fourth palpomere with 0–2 lanceolate or scalpellate sensilla chaeticae.

Antepronotal lobes well mostly strongly reduced medially, occasionally well developed, with 1–4 weak lateral setae. Acrostichals usually 2 side by side on mid-scutum, scalpellate in P. nana only; dorsocentrals usually uniserial, 3–24; prealars usually 1–6, occasionally 5–11 ( P. xanthostola and P. brevifurcata ); supraalar absent except for one side in a single specimen of P. roquei . Scutellum with 2–14 uniserial setae.

Wing membrane without setae, with moderately coarse punctuation of microtrichia, occasionally tinged with grey or brown. Anal lobe right angled, reduced or absent with wing cuneiform. Costa not to moderately strongly extended, often with false vein extending from apex of costa or R 4+5 nearly to wing apex; R 2+3 running medially between R 1 and R 4+5; R 4+5 ending slightly distal to, above or far proximal of end of M 3+4, often partly fused with costa in females; Cu 1 strongly to weakly sinuate, curved or straight; FCu ending far distal to RM; postcubitus extending well beyond FCu, often with an apical furcation; anal vein shorter than postcubitus. Brachiolum with 1 or occasionally 2–3 setae; R usually without setae in male, occasionally with 1–13 setae, with 1–11 setae in examined females; R 1 nearly always without setae in male, occasionally with 1–3 setae, with 0–11, usually 1–5 in female; R 4+5 nearly always without setae in male, occasionally with 1–4 setae, with 1–20 setae in female; costal extension with 0–1, usually 0, non-marginal setae in male, with 1–20 in female; costa between above RM and apex of R 4+ 5 in female with 0–42 nonmarginal setae, absent only in P. simplex . Squama bare. Sensilla campaniformia about 8–10 on base of brachiolum, 3 below setae and about 10–12 at apex of brachiolum, 1 on base of subcosta, 1 on FR and 1 on base of R 1.

Tibial spurs long and well developed on all legs although sometimes with 1 spur only on mid tibia. Hind tibial comb always well developed, consisting of 7–18 setae, less than 10 only in some specimens of P. digitrienta and in P. nana . Mostly weak relatively pale, occasionally strong, pseudospurs present at apex of ta 1 to ta 4 on all legs and often medially on ta 1. Sensilla chaetica usually absent on ta 1; present, but very weak subapically on ta 2 –ta 4 probably in all females and occasionally also in some males. Pulvilli small, vestigial or absent.

Tergites with irregularly arranged setae, in anterior and median transverse rows with some lateral setae, or only a few setae in an anterior transverse row.

Tergite IX of male without setae only in P. fusata , P. nana and apparently P. togativea , with 2 setae in P. parifusata , with 3–33 setae in other species. Anal point absent or usually present, base placed anteriorly on tergite; 71– 87 µm long in P. fusata , 0–57 µm long in other species; with or without basal setae, with microtrichia to apex; usually narrowly triangular, sometimes broadly triangular, occasionally rounded or narrowly parallel-sided, fusiform in P. fusata and P. parifusata , broadly parallel-sided with rounded apex in P. laticauda . Sternapodeme straight or arched, transverse sternapodeme reduced and unsclerotized in P. palpina ; oral projections occasionally well developed, sometimes weak or most commonly absent. Phallapodeme distinct, apodeme lobe occasionally wrinkled. Virga consisting of median, single plate and sometimes additional lateral rows of spinules or, in the lamellata group with lateral lamellae; median plate occasionally unsclerotized, more often fully sclerotized or with base and basilateral margins sclerotized with unsclerotized median and apical portions, giving the impression of a bifid virga; median virga usually 5–47 µm long, occasionally to 94 µm long (60–90 µm long in P. tokaraneoa , 64–94 µm long in P. guineensis , 71–73 µm long in P. digitrienta .) Gonocoxite normally 2–3 times as long as gonostylus, only 1.2 times as long in P. remigula , 1.5–1.6 times as long in P. digitrienta , 3.5–4.2 times as long in P. aculeathrix and P. umbonata . Volsellae highly variable; superior volsella absent, bulge-like to strongly developed, often digitiform; median volsella single or double; inferior volsella single or more often with accessory lobe which may be adpressed to gonocoxite or free at apex. Gonostylus variable in shape, broadest at base or at apex, tapering or parallel-sided, with or without well developed crista dorsalis, with or without outer heel, in P. mathildae , P. adunca , P. cambuciensis , P. catarinense , P. roquei and P. uncata bifurcate or bilobed, in P. gibbistyla Andersen, Saether et Mendes , P. magdae Andersen, Saether et Mendes , and P umbonata Andersen, Saether et Mendes indistinctly bilobed with secondary lobe adpressed either to inner margin of main lobe ( P. magdae ) or to outer margin of main lobe; megaseta single, sclerotized, 4–17 µm long.

Tergite IX of female sometimes undivided and, in P. guineensis even with an anal point, usually slightly to strongly divided into two setigerous protrusions separated by line to deep and wide notch, with altogether 2–23 setae; with characteristic sclerotized margin or apodeme against low but long and adpressed gonocoxites to each side. Gonocoxite with 1–9 strong setae and 0–12 weaker setae, setae scattered or concentrated on an apical low hump to, in P. zonata , strong projection. Gonapophysis VIII divided into small dorsomesal lobe widest in the middle, and large ventrolateral lobe. Apodeme lobe often distinct, often with parallel margins. Postgenital plate weak. Cerci of moderate size, shorter than length of notum, occasionally only half as long. Seminal capsules usually ovoid, occasionally circular, with large neck; with or without microtrichia occasionally with striations; usually dark sclerotized in apical 4/ 5, occasionally pale, spermathecal ducts with loop, occasionally with bulbs or widened before common or separate openings.

Pupa

Small to medium-sized pupae, length 1.2–4.2 mm. Exuviae infuscate on thorax, weakly infuscate on abdomen or nearly transparent.

Frontal setae present, on frontal apotome, spine-like and only 3 µm long in P. angusta and P. albipennis , hairlike and 10–80 µm long in other species. Frontal warts absent to distinct; frontal apotome smooth, occasionally wrinkled or with spinules or tubercles. Ocular field at least with 1–2 postorbitals.

Thorax with 2 median and 1–2 lateral antepronotals. Thoracic horn and precorneal tubercle absent. Three fine hair-like precorneals; 4 dorsocentrals, 3 posterior ones usually close together. All cephalothoracic setae fine and hairlike and not possible to measure accurately. Thorax smooth or occasionally with a few spinules. Wing sheath smooth, without pearls, without nose except in P. mathildae . Leg sheaths recurved beneath and not extending beyond apex of wing sheaths.

Tergite I bare, with weak to strong anterolateral shagreen, occasionally with caudolateral shagreen, or with both anterolateral and caudolateral shagreen; tergites II–VII either with shagreen consisting of similar-sized spinules covering most of tergites or with anterior and posterior spinules clearly larger than median spinules, resulting in a transversely striped appearance; tergite VIII with or without preapical area devoid of spinules; tergite IX usually with shagreen covering most of segment, occasionally with anterior and/or median shagreen only, occasionally bare, in P. mathildae and? P. obtusa with longitudinal ridge carrying strong spinules or spines, in P. holsata with pair of posterolateral mounds each carrying two strong contiguous teeth. Tergal conjunctives II/III or III/IV or (in P. angusta ) IV/V to V/VI (? P. obtusa ) or VI/VII or VII/VIII with rows of hooked spinules; or, in P. simplex , without spinules on tergal conjunctives. Sternites I–IV bare or usually variable shagreened with fine spinules, sternite V usually with fine anterior and posterior shagreen, sternites VI–VIIII with more extensive and coarse shagreen, sternite IX bare or with anterolateral and anteromedian shagreen. Sternal conjunctives bare in P. simplex and P. albipennis ; with minute spinules on V/VI–VII/VIII in P. paraconjuncta ; or with spinules of equal size to those on tergal conjunctives on III/IV or IV/V or V/VI to VI/VII (some specimens of P. mathildae ) or to VII/VIII (in most females) or to VIII/IX in most males. Apophyses weakly indicated. Pedes spurii A and B absent. Tergite I with 3 D setae, VIII with 2 D setae. Segment I with 3, II–VIII with 4 hair-like L setae. Apparently only 1 pair of dorsal O setae.

Anal lobe reduced, rounded without setae or with 2–3 anal macrosetae and 1 basilateral hair-like seta, with or without additional median seta. Male genital sac extending well beyond anal lobe, female genital sac reaching apex of anal lobe or extending slightly beyond; genital sac bare or with basal, ventral spinules, with or without additional apicolateral spinules or nearly covered by spinules; occasionally with apical papilla.

Larva

Small to medium-sized larvae, up to 6.2 mm long.

Antenna about 1/4 length of mandible; 4 segmented; basal segment at least as wide as long, occasionally nearly twice as wide as long; with apical ring organ (? always) and 2 oval sensilla basiconica at margin; with blade extending beyond flagellum as long as 2–4 times as long as width of basal segment; accessory blade as long as second or second and third segment combined. Second segment often sclerotized at base only, with large unsclerotized apical portion; subapical style characteristically pyriform; Lauterborn organ often indistinct, but large in comparison with antennal segment; segments 3 and 4 usually subequal in length, both shorter than second segment.

S I and S II both broad and bifid with basal collar particularly on S II, chaetae transversales present or absent or absent laterally to S II, chaeta media sometimes conspicuous, 0–2 spinulae. Pecten epipharyngis and median 2–4 chaetulae laterales consisting of simple scales, lateral 2–4 chaetulae laterales pale and strongly divided; chaetulae basales weak, pointed, single or split to base. Premandible with 2 apical teeth and 1–2 more or less tooth-like inner projections, with distinct brush. Mandible with 3–4 inner teeth, with or without 2 additional dorsal teeth; seta subdentalis usually present; seta interna absent.

Mentum with single median tooth with or without median projection, 4 pairs of lateral teeth, and large ventromental plates not extending beyond outer teeth on flattened mentum; beard absent. Maxilla with appendix seta and antaxial seta well developed; lacinial chaeta short, anterior lacinial chaeta not differentiated; pecten galearis and lamellae of galea absent; chaetulae of palpiger few, simple and scale-like; and maxillary palp well developed with two distinct levels. Premento-hypopharyngeal complex with median lamellae highly divided and serrated appearing as consisting of several toothed lamellae; paramedian lamellae also highly toothed, but with common base; pecten hypopharyngis consisting of scales with apical teeth for half their length.

Anterior parapods fused, with narrow basal spinules, each parapod usually with 5–8 ( P. paraconjuncta ) to about 50 larger serrated claws, occasionally ( P. simplex ) without longer claws. Posterior parapods vestigial without claws ( P. angusta , P. simplex ) to short with 0–5 or, in P. mathildae 8, smooth or serrated claws. Procercus absent, 1 anal seta. Two pair of anal tubules present, ventral pair usually larger than dorsal pair, occasionally with 1–2 constrictions, largest tubules usually subequal in length to length of posterior parapods, or when parapods vestigial, much longer than parapods.

Body setae very thin, hair-like and simple, often not discernible.