Elpidium Müller, 1880

Pereira, Julia S., Rocha, Carlos E. F., Pinto, Ricardo L. & DaSilva, Marcio B., 2022, Figs. 23 - 34 in The Newly Recorded Fern-spore Feeding Moths in the Genus, Meyrick 1889 (Lepidoptera: Stathmopodidae) from Taiwan, with Notes on Life History of Three Species., Zoological Studies 61 (27), pp. 1-17 : 3-11

Genus Elpidium Müller, 1880

Type species. Elpidium bromeliarum Müller, 1880 .

Species included in the genus: Elpidium maricaoensis ( Tressler, 1941) ; Elpidium laesslei ( Tressler, 1956) ; Elpidium inaequivalve Danielopol, 1981 ; Elpidium pintoi Danielopol, 1981 ; Elpidium purperae Danielopol, 1981 ; Elpidium merendonense Pinto & Jocqué, 2013 ; Elpidium martensi Danielopol et al., 2014 ; Elpidium littlei Pereira et al., 2019 ; Elpidium heberti Pereira et al., 2019 ; Elpidium wolfi Pereira et al., 2019 ; Elpidium litoreum sp. nov.

Diagnosis (modified after Pinto and Jocqué 2013): Medium to large sized carapace, generally with subtle ornamentation marked by minute individual or grouped foveolae (with the exception of Elpidium laesslei ). Brownish color, varying from light to dark. Width larger than height, ventral surface flat. Bisexual, with sexual dimorphism on both carapace and appendages varying from subtle to outstanding, but always present. Males with greatest width usually at mid-length; females broader than males posteriorly due to the existence of a brooding chamber, and greatest width displaced posteriorly. Antennula 5-segmented. First segment bearing dorso-apical expansion set with pseudochaetae. Antenna with 2 biserrate claws and 1 pectinate claw in males and 3 bisserrate claws in females; hyaline formation on terminal segment in both males and females. Maxillula with 2 spatulate claws in each second and third endites. Hemipenis greatly sclerotized; caudal ramus reduced to a pair of setae; copulatory process usually a hook-like structure with ejaculatory glans and ducts united or separated; distal lobe with dorsal seta, both varying in shape and size; lower ramus present and varying in shape; upper ramus absent. Females with abdomen rounded, bearing a stiff dorsal spine; caudal ramus reduced as in males; genital operculum sclerotized.

Elpidium litoreum sp. nov. Pereira, Rocha, Pinto and DaSilva ( Figs. 1–6 ) urn:lsid:zoobank.org:act:70B73BBB-35FB-4B16-A347-A41BE2B7F312

Diagnosis: Small-sized Elpidium , markedly elongated (length/width ratio = 1.4; length/height ratio = 1.9–2.0). Brownish carapace surface with sparse setae, normal pore canals and subtle ornamentation, represented by minute individual foveolae. In dorsal and ventral views, carapace symmetric. Ventral surface flat. In right lateral view, left valve overlaps right one in all margins; dorsal margin slightly arched, straight on the central portion; ventral margin arched, not straight; external antero-ventral flange well marked. Sexual dimorphism outstanding: in dorsal and ventral views posterior margin rounded in males while truncate in females. Hemipenis with left and right distal lobes elongated (distal lobe basis width/ distal lobe length ratio = 0.4), but asymmetric in shape: left one subquadrate, right one with curved apex; vestigial digital expansion present medially. Copulatory process a simple short hook-like ejaculatory duct. Lower ramus with broad basis, tapering towards lancet-shaped apex.

Type material: Holotype: a dissected ò ( MZUSP 38804 ) with valves dried and coated for scanning electron microscopy stored in a micropaleontological slide and appendages mounted in a sealed slide with glycerin . Allotype: a dissected ñ ( MZUSP 38805 ) stored like the holotype . Paratypes: a ò ( MZUSP 38820) and 2 ñ ( MZUSP 38807, MZUSP 38818) dissected and stored like the holotype; 3 ò ( MZUSP 38806, MZUSP 38808, MZUSP 38815) dissected with appendages mounted in a sealed slide with glycerin; 5 ò ( MZUSP 38812, MZUSP 38813, MZUSP 38814, MZUSP 38817, MZUSP 38819) and 4 ñ ( MZUSP 38809, MZUSP 38810, MZUSP 38811, MZUSP 38816) dried and coated for scanning electron microscopy stored in micropaleontological slides; about 136 ò and 150 ñ ( MZUSP 38821) kept whole in a vial with 70% alcohol.

Type locality: Tank-bromeliads from Praia Grande, Arraial do Cabo, Rio de Janeiro, Brazil. Approximate geographical coordinates: 22°98'S 42°03'W. Material collected in 11.x.2013 by Julia S. Pereira, Danielly G. Oliveira and Dariane I. D. Schneider.

Additional material: 3 ò ( MZUSP 38822, MZUSP 38830, MZUSP 38831) and 2 ñ ( MZUSP 38823, MZUSP 38824) dissected and stored like the holotype; 3 ò ( MZUSP 38825, MZUSP 38826, MZUSP 38828) and 2 ñ ( MZUSP 38827, MZUSP 38829) dried and coated for scanning electron microscopy stored in micropaleontological slides; 5 ñ ( MZUSP 38832) kept whole in a vial with 70% alcohol.

Locality: Tank-bromeliads from a rocky shore in Praia do Forno, Arraial do Cabo, Rio de Janeiro, Brazil. Approximate geographical coordinates: 22°57'S 42°00'W. Material collected in 11.x.2013 by Julia S. Pereira, Danielly G. Oliveira and Dariane I. D. Schneider.

Derivation of name: The specific epithet “litoreum ” refers to the occurrence of the species (and its host bromeliads) on the beaches of Arraial do Cabo, Rio de Janeiro, Brazil. It derives from the Latin adjective “litoreus”, meaning from the beach, coastal.

Description of the male: Carapace ( Fig. 1A–I ). Small-sized Elpidium (length of holotype = 629.8 µm), carapace elongated (length/width ratio = 1.4; length/ height ratio = 1.9). Color varying from light to dark brown. Subtle ornamentation numerous and minute individual foveolae. Normal pore canals and sparse setae present. In dorsal and ventral views, posterior region slightly broad; posterior margin rounded, not pointed; ventral surface flat. In right lateral view, left valve overlaps right valve on all margins; dorsal margin slightly arched, straight on the central portion; ventral margin arched, not straight; external antero-ventral flange outstanding.

Left valve ( Fig. 1J–L ): Flange present in anterior margin, absent in ventral and posterior margins. Selvage well marked in anterior margin; bow funnel-shaped structure in oral region. Calcified inner lamella broad in anterior and posterior regions; inner list well marked on anterior calcified inner lamella and subtle with a row of minute pseudochaetae on posterior calcified inner lamella. Vestibule broad in anterior and posterior regions. Adductor muscle scars 4-stacked spots on valve anterior third.

Right valve ( Fig. 1M–O ): Flange present in anterior, ventral and posterior margins, the latter one with sparse setae. Selvage well marked in anterior, ventral and posterior margins; bow funnel-shaped structure in oral region, interrupting flange. Calcified inner lamella broad in anterior and posterior regions; inner list subtle on anterior calcified inner lamella and well-marked on posterior calcified inner lamella. Vestibule broad in anterior and posterior regions. Adductor muscle scars 4-stacked spots on valve anterior third. Hinge about 2/3 of the dorsal margin extension; cardinal bar with 2 proto-teeth: posterior one more developed; bar and proto-teeth with very small crenulated ornamentation, visible only under high magnification.

Antennula ( Figs. 2A , 3A - represented by female specimen): 5-segmented. First segment relatively long bearing sub-apical expansion with a tuft of tiny pseudochaetae. Second segment the longest, with a single plumose seta in ventro-proximal position reaching fourth segment. Third segment square-shaped with a unique serrate seta in dorso-apical position that reaches fourth segment at about mid-length. Fourth segment bigger in length than in width and partially subdivided slightly before mid-length; medially with 2 dorsal sub-equal serrate setae and one ventral serrate seta; apically with a very long ventral serrate seta and 3 dorsal serrate setae: 1 short and 2 long, sub-equal length. Fifth segment (terminal) with 3 serrate and thin setae, 1 long and 2 equally short, plus an aesthetasc (Ya). Third, fourth and fifth segments with a row of pseudochaetae, covering whole or part of their apical portions.

Antenna ( Figs. 2B , 3B, E, F, 3C, D - represented by female specimen): Protopodite 2-segmented; coxa ring-shaped and basis long and arched, dorsally with 2 rows of tiny pseudochaetae and ventrally a triangular-shaped group of pseudochaetae. Endopodite 3-segmented. First endopodal segment relatively short, with very long serrate ventro-apical seta reaching apical portion of second endopodal segment; a group of pseudochaetae ventrally and 3 separated groups of long pseudochaetae dorsally, with each group reaching the next one in length. Second endopodal segment the longest, with a hardly visible vestigial seta apically, 2 sub-apical setae, 1 half as long as the other, dorsally and ventrally, about mid-length, a serrate seta and an aesthetasc (Y). Third segment (terminal) with 3 claws of sub-equal length, 2 serrate and 1 pectinate with a very strong row of denticles, besides tiny seta and hyaline formation. Exopodite very long and arched spinneret seta and vestigial basal seta.

Mandible ( Fig. 2F–H , represented by female specimen, 3G, H): Coxa internally with 8 strong teeth, modified X1 seta (spoon-shaped) and long plumose seta plus 2 interdental setae (X2 and X3), 3 interdental spines and sub-apical plumose seta. Palp 4-segmented: basis and 3 endopodal segments; basis with 2 setae in subapical position and respiratory plate (the exopodite) with 3 long setae and 1 short, reflexed seta, all with tiny setulae; first endopodal segment with 2 apical setae, 1 half as long as the other; second endopodal segment with 4 apical setae, 2 long and 2 short; third endopodal segment (terminal) with 3 setae, 2 thin and similar in length and 1 larger and longer than the other 2.

Maxillula ( Fig. 2E ): Bearing 3 endites. First one with 3 slender setae, approximately equally long; second and third endites with 2 spatulate claws and 3 smooth and slender setae each. Palp with about 4 rows of tiny pseudochaetae medially-positioned and 2 long plumose setae plus vestigial seta on apical portion. Respiratory plate (exopodite) well developed, with minute spines centrally and 16 rays plus 1 reflexed seta, all plumose.

First thoracic limb ( Figs. 4A , 5A–D ): Basis long and slightly arched with several rows of tiny pseudochaetae. Dorsal margin with medium-size plumose seta plus 2 short apical pappose setae wrapped in their basal portion by an expansion of segment. Exopodite a long and plumose seta. Endopodite 3 elongated segments. First segment the longest one, with several long pseudochaetae in both sides and one, strong biserrate seta, slightly shorter than second segment length; second segment devoid of setae; third segment (terminal) with strong and arched claw, slightly biserrate on its end and with tiny vestigial seta and row of pseudochaetae on its basis. All endopodal segments with rows of pseudochaetae in their apical and lateral portions.

Second thoracic limb ( Figs. 4B , 5E–G ): Similar to first thoracic limb in general shape, but longer. Basis with only 1 plumose seta on its apical portion, also wrapped by a segment expansion, but incompletely. Biserrate seta of the first endopodal segment and second segment equally long. Third segment (terminal) with strong apical claw, slightly longer and more arched than claw present on first thoracic limb terminal segment.

Third thoracic limb ( Figs. 4C , 5H–J ): Basis with 3 setae: 2 slender setae dorsally (1 in medial and 1, pappose, in apical position) plus 1 plumose exopodial seta ventrally in medio-proximal position. All 3 endopodal segments with length greater than width and their total lengths greater than in the first and second thoracic limbs. First segment with a unique biserrate seta equal in length to second segment and slightly more slender than its homologous structure in first and second thoracic limbs; second segment with transversal row of pseudochaetae on its lateral portion (structure absent from first and second thoracic limbs) and without seta; third segment (terminal) with very long and thin claw with vestigial seta on its basis. This latter structure biserrate as in first and second thoracic limbs, but not only in its end but in approximately 2/3 of its length. All 3 endopodal segments with rows of pseudochaetae in their apical and lateral portions, longer than those on first and second thoracic limbs.

Hemipenis ( Figs. 4 D , 5 K – M ): Large and sclerotized muscular body with copulatory complex (copulatory process and distal lobe) and furcal lobe as main structures. Furcal lobe with 2 pairs of mediumsized setae with numerous pseudochaetae. Distal lobe asymmetric; left one subquadrate, slightly longer than wide, apex acuminate; right one longer than wide, apex curved; both distal lobes with similar medium dorsal setae. Copulatory process simple (i.e., glans and ejaculatory duct united), short, hook-like. Lower ramus with broad basis, tapering towards lancet-shaped apex. Upper ramus absent.

Description of female: Carapace ( Fig. 6 ): Small-sized Elpidium (length = 622.6 µm). Carapace elongated (length/width ratio = 1.4; length/height ratio = 2). In dorsal view, posterior body region broader than in males due to the brooding chamber, posterior margin truncate. Ventral surface flattened. In right lateral view, central part of dorsal margin straighter than in males, ventral margin less rounded; external anteroventral flange greatly pronounced; left valve overlapping right one on all margins.

Antenna ( Figs. 2C, D , 3C, D ): Terminal segment with tiny seta, hyaline formation and 3 biserrate claws similar in length as opposed to males with 2 biserrate claws and 1 pectinate claw.

Abdomen ( Fig. 4 ): End of body rounded with 3 main structures: spine-like seta, female genital lobes and furcal lobes. Abdominal spine-like seta very stiff, dorso-medially placed; genital lobe rounded, rough, with a net of trabeculae internally; furcal lobe rounded, not rigid, with numerous pseudochaetae and 3 setae: first 2 inserted closely together and third one placed more anteriorly.

Remaining appendages: (i.e., antennula, mandible, maxillula, first, second and third toracic limbs) as described for male.

Comparison to other Elpidium species: Elpidium litoreum sp. nov. presents a high degree of sexual dimorphism on the carapace, like most Elpidium species. In all views, carapace is markedly elongated, similar to E. merendonense , a characteristic not usual for Elpidium . In dorsal view, males with posterior margin rounded as occurs in E. littlei and different from the usual acuminated posterior margin; females with posterior margin truncated as usual for the genus. In right lateral view, dorsal margin straight and ventral margin slightly arched as opposed to arched and straight as occurs in E. bromeliarum and most species of the genus; on the anterior margin an external flange is evident. E. bromeliarum and E. martensi also present this structure, although not quite evident, but slight. Distal lobes on hemipenis asymmetric, a feature hitherto unknown for the genus, at least for the species where this information can be assessed; left distal lobe somewhat similar to E. bromeliarum but with a longer external edge and less quadrate-shaped; right lobe resembles E. martensi but shorter and with a small apical projection on the internal margin. Elpidium litoreum sp. nov. hemipenis can also be differentiated from E. martensi by the morphology of the copulatory process and lower ramus. Copulatory process is simple (i.e., distal glans and ejaculatory duct united) as usual for the genus.

Phylogeny

Analysis performed in TNT resulted in a single most parsimonious tree ( Fig. 7 ), with a total length of 145.700, consistency index ( CI) of 0.644 and retention index ( RI) of 0.667. The reconstruction indicates three major results, supported by a number of synapomorphies: (1) Elpidium as a monophyletic group; (2) I. ibipora as its sister group; and (3) an internal division of Elpidium into two major groups: the Jamaican species E. laesslei , E. littlei , E. wolfi and E. heberti and, on the other hand, E. inaequivalve , E. purperae and E. pintoi from Cuba along with E. merendonense from Honduras, E. maricaoensis from Puerto Rico, E. martensi from Jamaica, E. bromeliarum and E. litoreum sp. nov. from Brazil.

Figures

Fig. 1. Elpidium litoreum sp. nov., ò, carapace. A, dorsal view (MZUSP 38812); B, dorsal view, detail of anterior region (MZUSP 38812); C, dorsal view, detail of posterior region (MZUSP 38812); D, ventral view (MZUSP 38813); E, ventral view, detail of anterior region (MZUSP 38813); F, ventral view, detail of posterior region (MZUSP 38813); G, right lateral view (MZUSP 38812); H, right lateral view, detail of anterior region (MZUSP 38812); I, right lateral view, detail of posterior region (MZUSP 38812); J, left valve, internal view (MZUSP 38819); K, left valve, internal view, detail of anterior region (MZUSP 38819); L, left valve, internal view, detail of posterior region (MZUSP 38819); M, right valve, internal view (MZUSP 38831); N, right valve, internal view, detail of anterior region (MZUSP 38831); O, right valve, internal view, detail of posterior region (MZUSP 38831). Scale bars: A, D, J, M = 100 µm; B, C, E, F, H, N, O = 20 µm; G = 30 µm; I = 10 µm; K, L = 50 µm.

Fig. 2. Elpidium litoreum sp. nov., A, B, E, ò, C, D, F–H, ñ, appendages. A, antennula (MZUSP 38815); B, antenna (MZUSP 38815); C, antenna (MZUSP 38818); D, antenna, terminal segment (MZUSP 38805); E, maxillula (MZUSP 38815); F, mandible, coxa (MZUSP 38805); G, mandible, basis (MZUSP 38805); H, mandible, respiratory plate (MZUSP 38805). Scale bars: A–C = 0.05 mm; D–H = 0.01 mm.

Fig. 3. Elpidium litoreum sp. nov., A, C, D, ñ, B, E–H, ò, appendages. A, antennula, detail of first segment, arrows point to the sub-apical expansion structure and to the two pseudochaetae rows (MZUSP 38816); B, antenna, detail of first protopodite segment (coxa), arrow points to the pseudochaetae row (MZUSP 38817); C, antenna, detail of second protopodite segment, arrows point to the numerous pseudochaetae rows (MZUSP 38816); D, antenna, first endopodal segment, arrows point to the three pseudochaetae groups (MZUSP 38816); E, antenna, second endopodal segment showing the aesthetasc (MZUSP 38817); F, antenna, portion of second endopodal segment and third endopodal segment, arrow points to the tiny vestigial seta (MZUSP 38817); G, mandible, portion of coxa (MZUSP 38817; H, mandible, portion of coxa, arrows point to the tiny spines (MZUSP 38817). Scale bars: A, D, E, H = 2 µm; B, C, F, G = 10 µm.

Fig. 4. Elpidium litoreum sp. nov., A–D, ò, E, ñ, appendages.A, first thoracic limb (MZUSP 38815); B, second thoracic limb (MZUSP 38815); C, third thoracic limb (MZUSP 38815); D, hemipenis (MZUSP 38815); E, abdomen (MZUSP38805). Scale bars: A–E = 0.05 mm.

Fig. 5. Elpidium litoreum sp. nov., ò, appendages. A, first thoracic limb, detail of protopodite and first endopodal segment, arrow points to the segment expansion that wraps the two protopodite setae basis (MZUSP 38817); B, first thoracic limb, arrow points to the short pseudochaetae group laterally placed on first endopodal segment (MZUSP 38819); C, first thoracic limb, arrow points to the short pseudochaetae group laterally placed on second endopodal segment (MZUSP 38819); D, first thoracic limb, detail of third endopodal segment and distal claw, arrow points to the transverse pseudochaetae rows on the segment (MZUSP 38817); E, second thoracic limb (MZUSP 38817); F, second thoracic limb, detail of third endopodal segment and distal claw, arrow points to the transverse pseudochaetae rows on the segment (MZUSP 38817); G, second thoracic limb, distal claw, arrows point to the transverse pseudochaetae rows on the apex and distal claw ending (MZUSP 38817); H, third thoracic limb, detail of second endopodal segment, arrows point to the pseudochaetae rows that transect the segment (MZUSP 38819); I, third thoracic limb, part of third endopodal segment, arrow points to the pseudochaetae rows that transect the segment (MZUSP 38819); J, third thoracic limb, detail of distal claw, arrows point to vestigial seta (MZUSP 38819); K, hemipenis (MZUSP 38817); L, hemipenis, detail of lower ramus and copulatory process (MZUSP 38817); M, hemipenis, detail of copulatory process (MZUSP 38817). Scale bars: A, C, D, G, J = 2 µm; B, I = 5 µm; E, H, K = 10 µm; F, M = 1 µm; L = 3 µm.

Fig. 6. Elpidium litoreum sp. nov., ñ, carapace. A, dorsal view (MZUSP 38811); B, dorsal view, detail of posterior region (MZUSP 38811); C, dorsal view, detail of anterior region (MZUSP 38811); D, ventral view (MZUSP 38810); E, ventral view, detail of posterior region (MZUSP 38810); F, ventral view, detail of anterior view (MZUSP 38810); G, right lateral view (MZUSP 38809); H, right lateral view, detail of posterior region (MZUSP 38809); I, right lateral view, detail of anterior region (MZUSP 38809); J, right lateral view, flange (MZUSP 38809); K, right lateral view, carapace ornamentation (MZUSP 38809); L, left valve, internal view (MZUSP 38807); M, left valve, internal view, detail of anterior region (MZUSP 38807); N, left valve, internal view, detail of posterior region (MZUSP 38807); O, left valve, internal view, detail of posterior region, arrow points to the tiny pseudochaetae row (MZUSP 38807); P, right valve, internal view (MZUSP 38816); Q, right valve, internal view, detail of anterior region (MZUSP 38816); R, right valve, internal view, detail of posterior region (MZUSP 38816); S, right valve, internal view, detail of posterior hinge proto-tooth (MZUSP 38816). Scale bars: A, D, G, L, P = 100 µm; B, E, F, H, I, M, N, Q, R = 20 µm; C, J, K, O, S = 10 µm.

Fig. 7. Most parsimonious tree showing monophyly of Elpidium as sister-group to Intrepidocythere and internal phylogenetic relationships within Elpidium. Tree obtained with software TNT (details in MATERIALS AND METHODS).