Ptecticus lanei James, 1941

Fachin, Diego Aguilar, Amaral, Edna Maria & Falaschi, Rafaela Lopes, 2024, Puparium of Merosargus cingulatus Schiner, 1868 and Ptecticus lanei James, 1941 (Diptera: Stratiomyidae: Sarginae), with new geographical records for the species and a list of all known immatures of the subfamily, Zootaxa 5406 (3), pp. 421-440 : 427-434

Ptecticus lanei James, 1941

( Figs 6–11 , 28–42 , 44)

Ptecticus lanei James, 1941: 301 . Holotype: male (MZUSP, examined in situ and by photos). Type locality: Brazil: São Paulo, Batêa (no coordinates are available).

Diagnosis of the adult (both sexes) (modified from Leal & Oliveira (1979)). Strongly marked of brown (sometimes nearly black) on the head, thorax, and abdomen ( Figs 6–11 ). Upper frons brown to black, darker in females. Pleuron dark brown on anespisternum, katerpisternum, and latero- and mediotergite mainly. Legs with coxae, trochanter, and at least basal half of femur dark brown; hind femur darker, with basal two-thirds dark brown. Abdomen mostly dark brown, with yellowish transverse bands over segments 1 to 5.

Material examined. Specimens with puparium. 1 ♂ (puparium without head), BRAZIL, Paraná, Carambeí, Alto do Carambeí , 24°55’30”S 50°04’51”W, 31.iii.2019 (emerged 17.iv.2019), emergence trap with fermented beans, Amaral, E.M ( MZUSP) ; 5 ♂ (1 coated with gold for SEM) , 1 ♀ (puparium coated with gold for SEM) , 23.xi.2019 (emerged 19.xii.2019), abóbora podre [= in rotting pumpkin], Amaral, E.M. (3 ♂, 1 ♀, MZUSP; 2 ♂, MNRJ) ; 1 ♂ (puparium without head), 23.xi.2019 (emerged 20.xii.2019) ( MZUSP) ; 3 ♀ (1 coated with gold for SEM) , 23.xi.2019 (emerged 21.xii.2019) (1 ♀, MZUSP; 2 ♀, MNRJ, 1 without head) ; 1 ♂ (puparium without head), 2 ♀ (1 without head), 23.xi.2019 (emerged 22.xii.2019) ( MZUSP) ; 1 ♀, 23.xi.2019 (emerged 27.xii.2019) ( MZUSP) ; 1 ♀ (puparium without head), 23.xi.2019 (emerged 30.xii.2019) ( MZUSP) ; 1 ♀, 23.xi.2019 (emerged 09.i.2020) ( MZUSP) . Specimens from the same collecting event, without puparium. 1 ♂, BRAZIL, Paraná, Carambeí, Alto do Carambeí , 24°55’30”S 50°04’51”W, 23.xi.2019 (emerged 16.xii.2019), puçá [= sweeping net], Amaral, E.M. ( MZUSP) ; 1 ♀, 23.xi.2019 (emerged 23.xii.2019), abóbora podre ( MZUSP) . Other material, without puparium . 1 ♂, BRAZIL, Espírito Santo, Santa Teresa, Est. [Estação] Biológica Santa Lúcia, 867 m, 19°58’36.0”S 40°32’06.4”W, Varredura, Ponto 41, 11.iv.2001, C.O. Azevedo & eq. col. ( MZUSP) ; 1 ♀, Est. [Estação] Biológica Santa Lúcia, 867 m, 19°58’37.3”S 40°32’22.5”W, Arm. Moericke, Ponto 1, Trilha 9, 12.iv.2001, C.O. Azevedo & eq col. ( MZUSP) . 1 ♂, 2 ♀, Minas Gerais, Botelhos, Córrego da Onça , 21°40’50”S 46°22’05”W, Malaise, Mata , 15.i–21.ii.2007, João Basso col. ( MZUSP) . 1 ♂, Rio de Janeiro, Rio de Janeiro , Pq. Est. [Parque Estadual] do Desengano , 21°50’S 41°40’W, 4° Malaise, Trilha, 17–20.iv.2002, Refugo ( MZUSP) . 1 ♂, São Paulo, Jundiaí, Pq. [Parque] Florestal da Serra do Japí, Cachoeira Sede , 23°14’12”S 46°55’58”W, Bandeja, 24.i.2007, Lecci, Nascimento & Polengatto cols. ( MZUSP) .

Literature records. James (1941), Leal & Oliveira (1979), and Fachin & Amorim (2015).

Description. Puparium. Total length, including head (n = 17): 14.2–15.0 mm. Cuticle with zigzag appearance on ventral and dorsal faces, well defined on ventral face ( Figs 28–31 ). Head. Subtriangular, moderately convex dorsally, longer than wide, although less than two times longer than wide, apical third, anteriorly to eyes, slender. Cuticle darker laterally, from posterior margin of head to base to apical third of head ( Figs 28 , 32 ). Maxillary palpus composed of a rigid, circular structure with rounded tip, much shorter than labrum in dorsal view ( Figs 28, 30 , 33 ). Labrum subrectangular, rounded at apex ( Fig. 28 ). Antenna (ant) small, two-segmented; basal antennomere (ba) at least two times wider than long; apical antennomere (aa) tapering towards apex, roughly as wide as long ( Fig. 37 ); antenna placed in a well-developed circular cavity, dorsal-laterally arising from the anterior part of head ( Figs 28 , 32 , 36 ), at the level of the second pair of labral setae. Eye (e) prominent, rounded, arising slightly above the middle part of head ( Figs 28 , 32 ). Molar area (mo) distinct transversely ridged ( Figs 30 , 33 ), as wide as the maxillary palpus in ventral view. Chaetotaxy: 2 pairs of labral setae (Lb), 2 pairs of clypeofrontal setae (Cf), 2 pairs of dorsolateral setae (Dl), 1 pair of lateral setae (L), 2 pairs of ventrolateral setae (Vl), 3 pairs of ventral setae (V), and 1 pair of ventroapical (Va) setae in the labral-molar area. Setae of head laterally flattened and barbed, usually lanceolate ( Fig. 36 ). Thorax. Rectangular; chaetotaxy: prothorax with 2 rows of setae in dorsal view, 2 pairs of anterodorsal setae (Ad), 2 pairs of dorsal setae (D), and 1 pair of dorsolateral setae (Dl); in ventral view, 1 pair of ventrolateral (Vl) and 2 pairs of ventral setae (V), (V1) simple and (V2) bipartite; prothoracic spiracle (prth spr) sclerotized, prominent. Meso- and metathorax with one row of setae each in dorsal view; mesothorax with 3 pairs of anterodorsal setae (Ad), 1 pair of dorsolateral setae (Dl), and 1 pair of lateral setae (L); in ventral view, 1 pair of ventrolateral setae (Vl) and 2 pairs of ventral setae (V), simple. Metathorax with 3 pairs of dorsal setae (D), 1 pair of dorsolateral setae (Dl), and 1 pair of lateral setae (L); in ventral view, 1 pair of ventrolateral setae (Vl) and 2 pairs of ventral setae (V), simple. Lateral setae lower in the external margin of the body than dorsolateral and ventrolateral setae ( Figs 28–31 ). Setae of thorax laterally flattened and barbed, usually lanceolate. Abdomen. Abdominal segments 1 to 7 similar in shape, slightly tapering from segment 5 to 7 ( Figs 29, 31 ); segments 1 to 6 with small lateral abdominal spiracles (abd spr) ( Figs 29, 31 ); chaetotaxy in segments 1 to 7 ( Figs 29, 31 , 39 ): each segment with a row of 3 pairs of dorsal setae (D) and 3 pairs of ventral setae (V); in segments 1 to 6, near the external margin of the body, 1 pair of ventrolateral setae (Vl), 1 pair of lateral setae (L), and 1 pair of dorsolateral setae (Dl), tiny setae from segments 2 to 6, longer in segment 1, each lateral setae lower in the external margin of the body compared to the other two; in segment 7, 1 pair of ventrolateral setae (Vl), 2 pairs of lateral setae (L), and 1 pair of dorsolateral (Dl), all longer setae. Segment 6 with a well-developed linear sternal patch ( Figs 31 , 35 , 38–40 ), nearly as much longer as the length of segment 6; it extends, not continuously, to posterior margin of segment 5 and sometimes to anterior margin of segment 7, unrelated to adult sexes. Segment 8 semicircular, tapering towards posterior margin ( Figs 29, 31 ); posterior margin nearly straight ( Figs 29, 31 ); cleft of posterior spiracle placed dorsally on segment 8, somewhat straight, with lower lip of opening bordered by flat and pinnate setae; anal slit with more than one-third the length of segment 8, placed in the basal half ( Figs 31 , 39 ); chaetotaxy: 1 pair of dorsal setae (D), 1 pair of lateral setae (L), 4 pairs of ventral setae (V), 1 pair of subapical setae (Sa), and 2 pairs of apical setae (Ap).

Notes on natural history. This is the first record of larvae/larval substrate of Ptecticus lanei .

Geographic distribution. Brazil (Bahia 1, Espírito Santo, Minas Gerais, Paraná, Rio de Janeiro, Santa Catarina, São Paulo) (Fig. 44). 1 Originally “ Bahia: Nova Conquista” (see Leal & Oliveira 1979: 91), now “ Bahia: Candido Salles”.

Comments. According to Leal & Oliveira (1979), adults of Ptecticus lanei resembles P. inops Lindner, 1949 in body coloration, as both species have dark brown markings on the pleura and dark brown horizontal bands over the abdominal segments, and in the hind leg dark brown coloration, which is on coxa, trochanter, and femur. We examined photos of the type specimens of both species, and they are similar, although P. lanei is darker, particularly on the pleura and abdomen. The most distinct feature to distinguish both species is the upper frons coloration in the head. In P. inops , it is markedly yellowish ( Leal & Oliveira 1979: 69), while in P. lanei , it varies from brownish (especially in males, see Fig. 10 ; also, in the holotype housed in the MZUSP collection) to dark brown, nearly black (in both sexes, see Fig. 11 ) ( Leal & Oliveira 1979: 90). There is also a variation in the hind femur coloration. In Leal & Oliveira’s illustrations (1979: 61, fig. 14), both species have nearly the same color pattern over the hind femur, only slightly less dark brown in P. lanei . Based on our observations of the type specimens, in P. lanei , the dark brown marking weakly exceeds the middle of the hind femur, while in P. inops , it surpasses that, and, similarly to Leal & Oliveira (1979: 61, fig. 14), only the fifth apical is yellowish. Additional specimens of P. lanei herein examined match the holotype of P. lanei with respect to the hind femur pattern, but this needs to be further examined in both species. As a same species of stratiomyid can show wide intraspecific variation (see Hermetia goncalvensi Albuquerque, 1955 in Fachin & Carvalho-Filho 2020; see H. brachygastropsis Fachin & Hauser, 2022 in Fachin & Hauser 2022), there is a chance that these two sympatric species, P. lanei and P. inops , are conspecific.

Figures

FIGURES 6–11. Ptecticus lanei James, 1941. 6–7. Habitus, dorsal and lateral views, respectively, male. 8–9. Habitus, dorsal and lateral views, respectively, female. 10–11. Head, dorsal view, male and female, respectively.

FIGURES 28–31.Puparium of Ptecticuslanei, illustration basedon images.28, 30. Head andprothorax,dorsal andventral views, respectively. 29, 31. Meso- and metathorax and abdominal segments, dorsal and ventral views, respectively.Abbreviations: 1–8, abdominal segments; I, prothorax; II, mesothorax; III, metathorax; ant, antenna; abd spr, abdominal spiracle; Ad, anterodorsal setae; Ap, apical setae; asl, anal slit; Cf, clypeofrontal setae; D, dorsal setae; Dl, dorsolateral setae; e, eye; L, lateral setae; lb, labrum; Lb, labral setae; mo, molar area; mx plp, maxillary palpus; p spr, posterior spiracle; prth spr, prothoracic spiracle; Sa, subapical setae; sp, sternal patch; V, ventral setae; Va, ventroapical setae; Vl, ventrolateral setae.

FIGURES 32–35. Puparium of Ptecticus lanei. 32–34. Head in dorsal, ventral, and lateral views, respectively. 35. Detail of the sternal patch, abdominal segments 5 to 6, ventral view. Abbreviations: ant, antenna; asl, anal slit; Cf, clypeofrontal setae; Dl, dorsolateral setae; e, eye; L, lateral setae; Lb, labral setae; mo, molar area; mx plp, maxillary palpus; sp, sternal patch; V, ventral setae; Va, ventroapical setae; Vl, ventrolateral setae.

FIGURES 36–42. SEM images of puparium of Ptecticus lanei. 36. Detail of the head, ventral view. 37. Antenna. 38, 40. Detail of the sternal patch. 39. Abdominal segments 5 to 8, ventral view. 41–42. Detail of the tegument of segment 6. Abbreviations: ant, antenna; asl, anal slit; Dl, dorsalateral setae; L, lateral setae; Lb, labral setae; Sa, subapical setae; sp, sternal patch; V, ventral setae; Va, ventroapical setae; Vl, ventrolateral setae.