Homoplectra japonica ( Banks 1906 )

Nozaki, Takao, 2025, Redescriptions of Homoplectra japonica (Banks 1906) and H. albomarginata (Ulmer 1907) (Trichoptera, Hydropsychidae), with descriptions of five new similar species from Japan, Zootaxa 5566 (2), pp. 303-328 : 305-308

publication ID

https://doi.org/10.11646/zootaxa.5566.2.4

publication LSID

lsid:zoobank.org:pub:9866D791-F9AA-4701-9EBC-B3A52613C657

DOI

https://doi.org/10.5281/zenodo.14718622

persistent identifier

https://treatment.plazi.org/id/03BD87A8-311C-FF94-FF2D-BACCD2E52699

treatment provided by

Plazi

scientific name

Homoplectra japonica ( Banks 1906 )
status

 

Homoplectra japonica ( Banks 1906)

( Figs 1A–1E View FIGURES 1–2 , 3 View FIGURE 3 , 11A–11E View FIGURES 11–12 , 13 View FIGURE 13 )

Arctopsyche japonica Banks 1906 , pp 111, 113, color pattern of male forewing.

Diplectrona japonica (Banks) View in CoL : Ulmer 1907, pp 72–74, figs 114, 115, changed combination.

Diplectrona japonica ( Banks 1906) View in CoL : Gyotoku & Nozaki 1991, pp 74–75, pl. 9, male (photo).

Homoplectra japonica ( Banks 1906) : Nozaki 2021, pp 254, 255, male, changed combination.

Diagnosis. The male of this species is very similar to that of Homoplectra flagelliformis sp. nov. but is distinguishable from the latter by the characters given in the diagnosis for that species.

The female is easily distinguishable from those of other Japanese species by the shape of a pair of large round basoventral lobes on the vulvar scale ( Figs 3H, 3I View FIGURE 3 ). Furthermore, female segment IX of this species has a pair of unique ventrolateral sclerotized plates that are oblong in dorsal and lateral aspects (marked with arrows in Figs 3G, 3I View FIGURE 3 ).

The larva is distinguishable from known Japanese larvae by the shape of anterior margin of the frontoclypeal apotome:Asymmetrical and sinuous in this species ( Figs 11A, 11B View FIGURES 11–12 ); but symmetrical in Homoplectra crassa Nozaki 2019 and Homoplectra tohokuensis Nozaki 2019 ( Nozaki 2019, figs 7A–7L, 8), bearing a small median triangular process in Homoplectra gracilis Nozaki 2019 ( Kochi et al. 2023, figs 3g, 3i), and asymmetrical and evenly convex mesally in H. albomarginata ( Figs 12A, 12B View FIGURES 11–12 ).

Description

Adult ( Figs 1A–1E View FIGURES 1–2 ). Head and thorax mostly dark brown dorsally, but dorsal setal warts of head, pro-, and mesonota with golden hair; face light brown in male, dark brown in female; compound eyes slightly larger in male than those in female ( Figs 1C, 1E View FIGURES 1–2 ). Legs mostly pale yellow to light brown; but middle and hind coxae of male and all coxae of female dark brown. Abdomen mostly dark brown, but pleural membranes pale yellow. Antennae light brown in male, dark brown in female, shorter than forewings; scapes thick, approximately as long as wide, with long hair-like setae dorsally ( Figs 1C, 1E View FIGURES 1–2 ); pedicels shorter than scapes, basal segment of each flagellum longer than scape ( Figs 1C, 1E View FIGURES 1–2 ). Wing venation similar in male and female. Forewings each 6.5–9.5 mm long in male (n = 11), 9.0– 11.5 mm long in female (n = 10), 6.5 mm in male lectotype; yellow, with broad dark stripes ( Fig. 1A View FIGURES 1–2 ); hind wings pale yellow with dark stripes ( Fig. 1A View FIGURES 1–2 ); venation of both wings as in Figure 1B View FIGURES 1–2 : with forks I, II, III, IV, and V in forewings and I, II, III, and V in hind wings; discoidal and medial cells closed in both wings. Tibial spurs 2-4-4. Abdominal sternum V with pair of finger-like processes associated with scent glands near anterolateral margins, slightly shorter than sternum ( Fig. 1D View FIGURES 1–2 ).

Male genitalia ( Figs 3A–3E View FIGURE 3 ). Ventrolateral sides of synsclerotized segment IX (IX) subtriangular in lateral aspect ( Fig. 3A View FIGURE 3 ); posteroventral lobe (p.l.) trapezoidal in ventral aspect, with shallow median concavity ( Fig. 3C View FIGURE 3 ); dorsal part of segment IX triangular with round and setose apex in dorsal aspect ( Fig. 3B View FIGURE 3 ), fused with segment X (X) laterally ( Fig. 3A View FIGURE 3 ). Segment X bilobed in dorsal aspect ( Fig. 3B View FIGURE 3 ), with pair of large posterolateral setose areas ( Figs 3A, 3B View FIGURE 3 ); each ventrolateral margin sclerotized, recessed into segment IX ( Fig. 3A View FIGURE 3 ). Inferior appendages (i.a.) each without distal segment, long and finger-like in lateral aspect, dorsal margin weakly concave at apical 1/ 5 in lateral aspect, extending beyond apex of segment X ( Fig. 3A View FIGURE 3 ); apex slightly enlarged mesally and truncate, with several short spine-like setae ( Figs 3A–3C View FIGURE 3 ). Basal plate of inferior appendages (b.p.i.a) sclerotized, subrectangular in ventral aspect ( Fig. 3C View FIGURE 3 ). Phallotheca with dorsal process (d.p.p.), acicular in dorsal and lateral aspects, weakly curved ventrad ( Figs 3D, 3E View FIGURE 3 ); with pair of ventral processes (v.p.p), long, approximately same length as dorsal process of phallotheca, each apex acute, curved dorsad and slightly mesad ( Figs 3D, 3E View FIGURE 3 ). Aedeagus (ae.) arising from membranous endotheca (end.), evenly curved ventrad, with long head approximately 1/4 as long as basal stem ( Fig. 3D View FIGURE 3 ); stem with lateral flanges, half-pipe-like, narrow at apical 3/4 and near base in dorsal aspect ( Fig. 3E View FIGURE 3 ), with pair of apical swellings in dorsal and ventral aspects ( Figs 3C, 3E View FIGURE 3 ).

Female genitalia ( Figs 3F–3I View FIGURE 3 ). Sternum VIII widely separated into pair of lateral lobes (l.l.) ventrally, each lobe bean-shaped in ventral aspect ( Fig. 3H View FIGURE 3 ). Segment IX (IX) obliquely rectangular in lateral aspect ( Fig. 3F View FIGURE 3 ), posterodorsal part trapezoidal in dorsal aspect ( Fig. 3G View FIGURE 3 ); tergum with pair of ventrolateral sclerotized plates (marked with arrows in Figs 3G, 3I View FIGURE 3 ), weakly constricted at mid-length in lateral aspect ( Fig. 3I View FIGURE 3 ), oblong in dorsal aspect ( Fig. 3G View FIGURE 3 ); each mesal lobe (m.l.IX) sclerotized, bean-shape in lateral aspect ( Figs 3F, 3I View FIGURE 3 ), forming large crevice between it and ventrolateral plate in ventral aspect (marked with arrow and asterisk in Fig. 3H View FIGURE 3 ); pair of sclerotized ribs (s.r.) forming large round plate-like lobes on vulvar scale (v.s.) basoventrally ( Figs 3H, 3I View FIGURE 3 ). Vulvar scale large, tongue-like in ventral aspect ( Fig. 3H View FIGURE 3 ), semimembranous apically. Segment X slender in lateral aspect ( Fig. 3F View FIGURE 3 ). Vaginal apparatus (v.a.) long-pentagonal in dorsal aspect ( Fig. 3G View FIGURE 3 ), tapering to duct of bursa copulatrix (d.b.c.); with pair of peanut shape sclerites posterodorsally, with pair of longitudinal ridges dorsally, and with dark arched marking anterodorsally, partially surrounding opening of duct of spermatheca (d.s.).

Final instar larva ( Figs 11A, 11B, 11F View FIGURES 11–12 ). Head 1.6 mm wide (n = 1), approximately as long as wide ( Fig. 11F View FIGURES 11–12 , hl, hw); frontoclypeal apotome asymmetrical in dorsal aspect ( Fig. 11B View FIGURES 11–12 inset), maximum width 1.2 mm, posterior angle about 90°, with anterior margin sinuous, left side recessed, very weakly concave in middle, with most secondary setae clavate. Mandibles each with 5 teeth. Pronotum with transverse sulcus on posterior 1/4 ( Fig. 11A View FIGURES 11–12 ). Meso- and metathorax and abdominal segments bearing gills, with one pair of ventral tufts of gills on mesothorax and abdominal segment VII, with two pairs of subventral tufts of gills on metathorax and each of abdominal segments I to VI, with 1–3 sublateral conical gills on each of abdominal segments III to VII. Secondary setae on thoracic nota and abdominal segments mostly clavate.

Pupa ( Figs 11C–11E View FIGURES 11–12 ). Body length 10 mm (n = 1). Mandibles slender, with 3 (right) or 4 (left) apical and subapical teeth, each mandible with stout mesal plate-like projection on apical 1/3. Middle tarsi bearing sparse hair-like setae. Abdominal segments with dorsal hook plates anterior on II to VIII, posterior on III and IV ( Figs 11C, 11D View FIGURES 11–12 ). Abdominal segments bearing gills, with one pair of ventral tufts of gills on each of abdominal segments II to VI, with lateral conical gills on each of abdominal segments III to VII. Anal processes sclerotized, ventral surfaces covered by tiny spines; bifurcated, each apex acute, mesal branch longer than outer one ( Fig. 11E View FIGURES 11–12 ).

Lectotype: Male (here designated, pinned: MCZ:Ent:11833): labeled “type”, “ Hikosan , Buzen , Japan ”, “Collection N. Banks”, “ Arctopsyche japonica Banks /type”, “Type 11833”, “ Trichoptera : Diplectrona japonica wings from Type/Det. H.H. Ross, 19/ILL. NAT. HIST. SUR (right wings in slide)” (https://mczbase.mcz.harvard. edu/guid/MCZ:Ent:11833; Nozaki 2021, fig. 5).

Specimens examined. JAPAN: HONSHU: Yamaguchi: 1 male, Nankai, Atojifukushimo, Yamaguchi-shi , 17.v.1993, N. Kuhara. KYUSHU: Fukuoka: 1 female, Mt. Hiko-san , Soeda-machi , 31.v.1935, K. Yamauchi ( KPM); 11 males, 9 females, same locality, 19.v.1993, N. Kuhara (6 males, 3 females: KuN); 1 male, 1 female, same locality, 9.vi.1994, T. Nozaki (1 male: SPMN); 1 male pupa with larval exuviae, 1 larva, same locality, 22.v.1996, T. Hattori ( SPMN); 1 male, Mt. Kosho, Asakura-shi , 18.v.1969, N. Gyotoku ( KPM); 1 pupa, 2 pupal remnants with larval exuviae, Dobaru (alt. 200 m), Kokuraminami-ku, Kitakyushu-shi , 17.iv.2004, T. Hattori ( SPMN). Oita: 1 male, Shimizubakuen, alt. 450 m, Mori, Kusu-machi , 18.iv.2004, T. Hattori ( SPMN) .

Distribution. Westernmost Honshu, northern Kyushu.

Biology. Larval and pupal specimens of this species were collected from small streams in hilly and mountainous areas.

Japanese name. Kimadara-shima-tobikera.

Remarks. Banks (1906) described A. japonica from Fukuoka, Kyushu and Gifu, central Honshu as “Hikosan, Buzen [now Fukuoka], Japan, 28 April; also from Gifu ”, but no holotype was designated. Nozaki (2021) transferred this species to the genus Homoplectra based on examination of photographs of a syntype male (MCZ:Ent:11833) collected from Fukuoka and deposited in the Banks collection of MCZ. In this study, I examined photographs of another specimen also deposited in the Banks collection as a syntype (MCZ:Ent:648191) kindly provided Dr. C. W. Farnum (MCZ). Since this specimen had a handwritten label “ Gifu Japan ” (https://mczbase.mcz.harvard.edu/ guid/MCZ:Ent:648191), the record from Gifu in the original description by Banks (1906) must have been based on it. Although I could not examine its genital morphology because of mold covered the abdomen, the length of the scape of left antenna (right antenna missing) was apparently longer than its width. Since the syntype male collected from Fukuoka has a short scape ( Nozaki 2021, fig. 5A), these two specimens must belong to different species. Thus, I designate here the male collected from Fukuoka (MCZ:Ent:11833) as the lectotype to fix the status of the taxon name.

As a result of the lectotype designation of A. japonica , another specimen (MCZ:Ent:648191) becomes a paralectotype. Although I could not identify this specimen at the species level, H. albomarginata is widely distributed in Gifu Prefecture and the scape of each antenna ( Figs 2B, 2C View FIGURES 1–2 ) is longer than that of H. japonica ( Figs 1C, 1E View FIGURES 1–2 ). Ulmer (1907) recorded H. japonica (as D. japonica ), also from Gifu; but it was a misidentification of H. albomarginata (see the Remarks for that species).

MCZ

USA, Massachusetts, Cambridge, Harvard University, Museum of Comparative Zoology

KPM

KPM

MCZ

Museum of Comparative Zoology

KPM

Kanagawa Prefectural Museum of Natural History

T

Tavera, Department of Geology and Geophysics

Kingdom

Animalia

Phylum

Arthropoda

Class

Insecta

Order

Trichoptera

Family

Hydropsychidae

Genus

Homoplectra

Loc

Homoplectra japonica ( Banks 1906 )

Nozaki, Takao 2025
2025
Loc

Arctopsyche japonica

Banks 1906
1906
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