Smicridea (Smicridea) polyacantha Desiderio, Pes & Hamada, 2021

Desiderio, Gleison Robson, Pes, Ana Maria, Andrade-Souza, Vanderly & Hamada, Neusa, 2021, The Smicridea (Smicridea) fasciatella species group (Trichoptera: Hydropsychidae) in Brazil: six new species and new distributional records, European Journal of Taxonomy 750 (1), pp. 156-196 : 179-182

Smicridea (Smicridea) polyacantha Desiderio, Pes & Hamada sp. nov.

urn:lsid:zoobank.org:act:3D7EB67E-4896-419A-AC6C-A1171653B9F0

Figs 3 , 4F , 13 – 14

Diagnosis

This new species is a distinct member of the fasciatella group due the presence of small endothecal spines on the apex of the phallic apparatus. Smicridea polyacantha sp. nov. and S. paranensis are the sole species in the group that share this character. However, the new species has 40 conical endothecal spines grouped in a V-shaped arrangement in dorsal view, while S. paranensis has numerous fine spines organized in four rows. Additionally, the apex of the apical segment of the inferior appendage is rounded in the new species and obliquely truncated in S. paranensis . The phallotremal sclerite has a proximal region that is bifid, curved downward in lateral view, and a dorsolateral projection on the distal region that is unique in S. polyacantha sp. nov.

Etymology

The specific epithet is an allusion to the large number of endothecal spines present on the apex of the phallus. Derived from the Greek words, ʻ poly ʼ = ʻveryʼ or ʻmanyʼ and ʻ akantha ʼ = ʻspineʼ.

Material examined

Holotype BRAZIL • ♂; Amazonas, Manaus, BR–174, Balneário Km 18.5; 02°49′00.80″ S, 60°02′05.60″ W; 33 m a.s.l.; 27 Oct. 2009; A.M.O. Pes, J.O. Silva and R. Boldrini leg.; white sheet with an LED light; INPA-TRI 000117 .

Paratypes BRAZIL • 18 ♂♂; same collection data as for holotype; INPA-TRI 000118 • 1 ♂; same collection data as for holotype; 7 Apr. 2009; INPA-TRI 000119 • 2 ♂♂; same collection data as for holotype; 22 Jan. 2009; DZRJ • 3 ♂♂; same collection data as for holotype; Nov. 2012; DZUP • 5 ♂♂; Novo Airão, Igarapé Mato Grosso; 02°49′03.8″ S, 60°55′47.1″ W; 24–26 Nov. 2014; R.L.F. Keppler and J.O. Silva leg.; Pennsylvania trap; MZUSP • 1 ♂; Mato Grosso, Sapezal, MT–235, Rio Papagaio , outside indigenous reserve; 13°33′39.5″ S, 58°24′24.2″ W; 473 m a.s.l.; 31 Oct.–1 Nov. 2012; N. Hamada and J.M.C. Nascimento leg.; Pennsylvania trap; INPA-TRI 000120 .

Description

Adult male ( Figs 13–14 )

FOREWING LENGTH. 3.61–4.02 mm (mean = 3.79, SD = 0.15, n = 6).

COLOR. General color dark brown (in alcohol) ( Fig. 13A ). Antennae yellowish brown ( Fig. 13A ). Head dark brown, with brown setae on dorsum ( Fig. 13B–C ); dorsally with weakly pronounced median suture; with five setal warts; anteromesal wart small, rounded; anterolateral pair undivided, weakly delimited; posterolateral pair large, ovoid ( Fig. 13C ). Maxillary palp with segments 1–4 increasing gradually about 0.8× in size toward more apical segments, segment 5 long, about 1.2× as long as all previous segments combined ( Fig. 13B ). Thorax dark brown, covered with pale-brown setae; legs brown, with mid-leg tarsi yellowish ( Fig. 13A ). Wing venation typical for subgenus ( Fig. 13D–E ). Forewings, in alcohol, brown, with white transverse band subapically on pterostigma reaching base of R4+5 and small white spot on apex of Cu2 ( Fig. 13D ). Sternum V with anterolateral glandular processes slightly shorter than sternum. Abdominal segments VI and VII with 2 pairs of internal glands, both pairs as long as their containing segments ( Fig. 13F ).

MALE GENITALIA ( Fig. 14 ). Segment IX in lateral view with anterolateral margin nearly straight, weakly sclerotized ( Fig. 14A ); posterodorsal margin bearing small spicules, distributed in two rounded bands ( Fig. 14B ). Tergum X elongate; in lateral view, ventrolateral margin slightly sclerotized, with five long, thin setae on apical third; apex produced and upturned ( Fig. 14A ); in dorsal view, lateral margin straight; dorsomesal setose area bearing two medium-sized, thin setae; divided apicomesally by a V-shaped incision about ½ its length; apex of tergite slightly pointed, with small apicomesal lobe and about six mediumsized, thin setae ( Fig. 14B ). Inferior appendages 2-segmented; basal segment long, slightly inflated distally, covered with medium-sized, thin setae, with one long, stout subapical spine-like seta on mesal margin; apical segment short, about ⅓ as long as basal segment, thick, slightly curved medially, apex rounded with numerous short, thin setae on mesal margin ( Fig. 14B ). Phallic apparatus long and tubular; basal section, in lateral view, enlarged, 3× diameter of phallotheca at its narrowest point, forming an angle of about 116° with apical section; median section of phallotheca straight, with dorsal periphalic cap sclerotized, slender and upturned ( Fig. 14C ); apex slightly enlarged, without processes or plates; endothecal membranes with 40 small, conical spines, grouped in a V-shaped arrangement and directed posterad; phallotremal sclerite, in dorsal view, distinct, strongly sclerotized, proximal region bifid, curved downward in lateral view and directed posterad, distal region with dorsolateral projections more than half length of sclerite, broad apically, folding and touching dorsomesally, and with another pair of slender ventrolateral projections curved downward and directed anterad ( Fig. 14D–E ); in lateral view, proximal and distal regions hooked, not parallel in proximal region ( Fig. 14C ). Ejaculatory duct of endophallus, in lateral view, indistinct ( Fig. 14C ). When endothecal membranes are everted, phallotremal sclerite modified into two dorsolateral slender lobes, forked at apex, connected to a dorsomesal ring, and apical spines divided into two lateral lobes with 20 spines each, in lateral view, directed anterad ( Fig. 14F–G ).

Bionomics

This species was collected near medium-sized streams with slow flow in central Amazonia. The streams were strongly impacted by human activities, especially recreational use (swimming) and road building ( Fig. 4F ). These streams have sandy bottoms and are characterized by Dense Ombrophilous Forest Lowlands to Dense Ombrophilous Forest. Only one male of S. polyacantha sp. nov. was collected near a large river (Rio Papagaio) with fast-flowing water and a rocky bottom, located in the western part of the Brazilian Cerrado, where the vegetation is composed by Primary Savanna, Seasonal-Forest Savanna, and Wooded Savanna. The surroundings of this region are also strongly impacted by agricultural and pasture activities.

Distribution ( Fig. 3 )

Brazil: Amazon (Amazonas), Cerrado (Mato Grosso).

Figures

Fig. 3. Geographical distribution map for the new species of Smicridea McLachlan, 1871 treated in this study.

Fig. 4. Habitats of the new species of Smicridea McLachlan, 1871 treated in this study: A. First-order stream, Amazonas, Brazil, collection site of Smicridea (Smicridea) blahniki Desiderio, Pes & Hamada sp. nov. B. Rio Irani, Santa Catarina, Brazil, collection site of S. (S.) brevitruncata Desiderio, Pes & Hamada sp. nov. C. Arroio Lajeado, Rio Grande do Sul, Brazil, collection site of S. (S.) caaguara Desiderio, Pes & Hamada sp. nov. holotype. D. Cascata Raddatz, Arroio Teotônica, Rio Grande do Sul, Brazil, collection site of S. (S.) caaguara sp. nov. paratype. E. Igarapé Ipiranga, Amazonas, Brazil, collection site of S. (S.) ipiranga Desiderio, Pes & Hamada sp. nov. F. Balneário Km 18.5, Amazonas, Brazil, collection site of S. (S.) polyacantha Desiderio, Pes & Hamada sp. nov.

Fig. 13. Smicridea (Smicridea) polyacantha Desiderio, Pes & Hamada sp. nov., holotype, ♂ (INPA-TRI 000117). A. Dorsal habitus. B. Head, right lateral view. C. Head, dorsal view. D. Forewing, right dorsal view. E. Hind wing, right dorsal view. F. Abdominal segments IV–VIII, ventral view. Scale bars in mm: A = 2; B–C = 0.5; D–F = 1.

Fig. 14. Smicridea (Smicridea) polyacantha Desiderio, Pes & Hamada sp. nov., male terminalia. – A–E. Holotype (INPA-TRI 000117). A. Terga IX, X and inferior appendages, lateral view. B. Same, dorsal view.C. Phallus, lateral view.D.Apex of phallus, dorsal view.E.Apex of phallus (photograph). –F. Paratype (MZUSP), apex of everted phallus (photograph), lateral view. – G. Paratype (INPA-TRI 000119), apex of everted phallus (photograph), dorsal view. Scale bars in mm: A–C = 0.1; D–G = 0.05.