A revision of the genus Rudolfina Roháček (Sphaeroceridae: Limosininae) Author Paiero, Steven Mark Author Marshall, Stephen A. text European Journal of Taxonomy 2020 2020-01-16 593 1 48 journal article 24112 10.5852/ejt.2020.593 16dfaaea-fa3b-4dda-a047-13359b05bfa1 3659777 B08C59C9-6F91-4F3B-B595-5C6E7E6710D0 Genus Rudolfina Roháček, 1987 Rudolfia Roháček, 1982: 225 (feminine, a junior homonym of Rudolfia Wilson, 1924 (Crustacea: Copepoda); type species: Limosina rozkosnyi Roháček, 1975 , by monotypy). Rudolfina Roháček, 1987: 474 (feminine, nom. nov. for Rudolfia Roháček, 1982 ; type species: Limosina rozkosnyi Roháček, 1975 , automatic). Rudolfia – Roháček 1982: 225 [formal diagnosis, phylogeny]; 1983: 152–154 [full description, phylogenetic notes]; 1987: 474 [homonymy]. — Marshall & Richards 1987: 999–1000 [diagnosis in key, illustr.]. Rudolfina – Roháček 1998: 483 [diagnosis, illustration]. — Marshall & Buck 2010: 1180–1183 [diagnosis in key, phylogenetic notes, biology]. — Su et al. 2017: 392–393 [key]. Redescription BODY. Colour light to dark brown. Length 1.4–2.3 mm . HEAD. With 3–5 interfrontal setae (of equal length or the foremost shorter), 1 (rarely 2) inclinate orbital setula and 4–10 small orbital setulae inside and below 2 strong, exclinate orbital setae; ocellar triangle with pair of strong setae and 3–5 additional small setulae; outer vertical seta strong, exclinate; inner vertical seta inclinate; occipital and paravertical setae inclinate, well-developed; postocellar seta inclinate, weakly developed. Eye-to-gena height ratio variable between species (1.5:1 to 3.5:1). Vibrissa strong. Gena with 1–2 strong subvibrissal setae and 4–9 smaller setulae. THORAX. Surface pruinose. Postpronotal lobe with 2–3 setae, outer seta strong, inner seta(e) reduced. Notopleural seta, 2 supra-alar setae and prescutellar dorsocentral seta strong. Acrostichal setulae in 4–8 rows, with 1 enlarged prescutellar acrostichal seta (almost as long as dorsocentral). Katepisternum with strong elongate posterior seta and reduced anterior seta. LEGS. Fore femur with 3–5 elongate setae dorsally (except R. exuberata sp. nov. ). Fore tibia with 3–5 elongate setae ventrally. Mid femur with row of 3–10 anterodorsal setae extending from base, row of 2–5 dorsal setae on apical ¼, and basal cluster of 4–21 small setae ventrally; males usually with additional ventral seta (often in ventrobasal cluster). Mid tibia with 4 dorsal setae (basal anterodorsal, medial anterodorsal distal anterodorsal and distal posterodorsal); males with ventral comb of 4–13 setae on apical ½ or less ( , R. exuberata sp. nov. and R. remiforma sp. nov. with setae of ventral comb weakly developed); females usually with midventral seta (absent in R. megepandria sp. nov. ). Hind tibia with small apical ventral spur. WING. Always fully developed, with wing tip reaching or exceeding apex of abdomen. Costa extending to or just beyond end of R 4+5 , and with single costagial seta> 2.0 × length of nearby setae. R 4+5 slightly curved towards costa distally. Cell dm with short stub veins of M 1 and Cu-A1 extending beyond dm-cu. Alula narrow, posterior margin straight. ABDOMEN. Sternites and tergites well sclerotized and setose (posterior and lateral margins more densely setose). Male sternite 4 usually simple (rarely densely setose medially). MALE ABDOMEN. Posterior margin of sternite 5 with lobe on each side of medial emargination (shape and size of emargination and lobes vary among species). Transverse (ventral) portion of sternite 6 narrow; straight or weakly arcuate. Ring sclerite (in the right membrane of segment 7, possibly derived from a spiracle) large and distinct. Epandrium setose, often with larger setae lateral to anal opening, and with right anteroventral corner drawn out into a finger-like process that extends to the hypandrium. Male cercus usually distinct, fused with the epandrium (reduced and obscured beneath the epandrium in a few species; e.g., R. pilosa sp. nov. , R. remiforma sp. nov. ). Hypandrium ( Fig. 3B ) Y-shaped with emarginate posteromedial extension; hypandrial arms posteriorly deeply bilobed posteriorly, with lateral lobe articulating with the epandrium and the medial lobe articulating with posterolateral corner of hypandrium. Pregonite distinct, small, near anterior base of postgonite. Postgonite generally simple and slender, with 3–4 setulae on anterior margin but modified in some species; ejaculatory apodeme small and finger-like, with small globular sperm pump, usually close to the basiphallus (easily lost during dissection); basiphallus simple (without an epiphallus); distiphallus with distinct elongate dorsal sclerite; acrophallus with dorsolateral lobes and a single ventral sac (often reduced). FEMALE ABDOMEN. Tergite 8 apparently tripartite, with two lateral triangular sclerites and a medial sclerite (reduced in several species). Epiproct bare except for usual pair of small setae and a few scattered setulae, strongly sclerotized, and fused laterally with cerci (except in R. cavernicola ). Cercus with single flattened apical seta. Sternite 7 variable. Sternite 8 weak, transverse, covered in small setulae; pair of small, bispinose plates along posterior margin. Hypoproct very narrow, forming horseshoe-shaped band immediately below the cerci. Spermathecae (1 pair + 1 single) generally disc-shaped or lenticular, with thin, long sclerotized ducts. Related and similar genera All species of Rudolfina will key out to “ Rudolfia ” in the key to Nearctic Sphaeroceridae by Marshall & Richards (1987) but they will key out as “ Archiceroptera genus complex, in part” at couplet 72 in the key of Marshall & Buck (2010) to Neotropical Sphaeroceridae . This previous treatment reflected uncertainty about the limits between Rudolfina and the many undescribed Neotropical species in the Archiceroptera genus complex. The Archiceroptera complex is part of a larger group of Limosininae (including Aptilotella Duda, 1924 , Archiceroptera Papp, 1977 , Bitheca Marshall, 1987 , Bromeoloecia Spuler, 1924, Pterogramma Spuler, 1924 and Robustagramma Marshall & Cui, 2005 ) characterized by an unusual process extending medially from the lower right margin of the epandrium to the hypandrium. The relationships within this group need further study but the morphological analysis by Paiero (2017) suggests that Rudolfina is closely related to Bromeloecia . Within this group, Rudolfina resembles Archiceroptera in characters of the female epiproct and cercus. However, in Archiceroptera the epiproct is completely desclerotized medially (anteriorly sclerotized in Rudolfina ), the cercus is separate from the epiproct and has a partially concave inner margin, and sternite 8 is divided into a pair of elongate lateral sclerites without the paired setulose sclerites found in Rudolfina . Archiceroptera species also differ from Rudolfina in having M 1 extending as a pseudovein to the wing margin, CuA 1 rarely with a distinct stub vein, the male cercus free from the epandrium and with a distinct ventral process, and (in many, but not all species) five or more dorsal mid tibial setae and two or more inclinate orbital setulae. Biology Roháček (1987) recorded R. rozkosnyi from dung and occasionally from mud and decaying vegetation, but most of the new species considered here were collected in dung or carrion traps. Larvae remain unknown. Distribution Rudolfina has a mostly western Nearctic montane distribution, with high endemism in the southwest and the mountains of Mexico (Sierra Madre del Sur, Sierra Madre Oriental and Sierra Madre de Chiapas ). Two widely separated species occur in the Palaearctic region ( R. rozkosnyi and R. zhangi ) and one species ( R. exuberata sp. nov. ) is widespread at low elevations from the southern United States to South America. Other than R. exuberata sp. nov. , no true species of Rudolfina are known from south of Guatemala . Other Neotropical species previously treated as Rudolfina are discussed below. Results of the phylogenetic analysis Twenty-seven most parsimonious trees were generated, summarized here as a strict consensus tree ( Fig. 5 ) and a majority rules consensus tree ( Fig. 6 ). Characters were optimized on one of the equal length trees ( Fig. 7 ) which was selected based on the recovery of several groups supported by putatively higher weight characters. Shared male genitalic morphology supported a close relationship of Rudolfina bucki sp nov. with R. megepandria sp. nov. and R. tumida sp. nov. with [ R. rozkosnyi + R. digitata + R. zhangi ]. The combined elongation of the epiproct and female cercus suggests that R. newtoni sp. nov. is closely related to [ R. exuberata sp. nov. + R. pauca sp. nov. + R. remiforma sp. nov. ], although the form of the epiproct in R. newtoni sp. nov. is apparently intermediate between the strongly elongated form found in the R. exuberata clade and the shorter epiproct of other Rudolfina . All trees recovered R. cavernicola as a sister taxon to the remaining species, which form a monophyletic group characterized by the fusion of the female cercus with the posterolateral corner of the epiproct, the elongation of the medial part of tergite 8 and by characters of the male cercus and surstylus. This tree suggests a New World origin for Rudolfina . Within Rudolfina excluding R. cavernicola , R. rozkosnyi , R. digitata and R. tumida sp. nov. appear to be a basal grade predating the origin of a clade comprising the Mexican-Guatemalan species. These four species all have a laminate lobe on the surstylus, apparently derived from the simple laminate margin of R. cavernicola (absent in other species). The largely Mexican-Guatemalan clade can be recognized by the simple, rounded anterior lobe of the male surstylus and the absence of dorsal swellings on the dorsal sclerite of the distiphallus. The R. exuberata group (including R. exuberata sp. nov. , R. remiforma sp. nov. and R. pauca sp. nov. ) is characterized by a small elongate male cercus, tulip-shaped epiproct, and reduction of the female cercus. Rudolfina remiforma sp. nov. and R. pauca sp. nov. are known from only a few localities at higher elevations, as is typical of the genus, but the widespread R. exuberata sp. nov. occurs at much lower elevations than its more localized congeners. Fig. 5. Strict Consensus Tree for the 27 recovered trees obtained from Traditional Search (TNT). Fig. 6. Majority Rules Consensus Tree from the 27 recovered trees retained from Traditional Search (TNT). Key to the New World Rudolfina Accurate identification of species of Rudolfina is largely dependent on examination of male sternite 5 and genitalic characters of both sexes; dissection may be required. Females of R. tumida sp. nov. , R. bucki sp. nov. , R. pilosa sp. nov. and R. zhangi are unknown. 1. Males ................................................................................................................................................. 2 – Females ........................................................................................................................................... 14 2. Sternite 5 with dense clusters of setae on each side of posteromedial emargination ( Figs 14C , 18C ) ................................................................................................................................................... 3 – Sternite 5 evenly setose, without distinct clusters of setae ............................................................... 4 3. Eye height ~2.5 × genal height. Sternite 4 medially with cluster of long setae (denser along posterior margin, Fig. 18C ). Sternite 5 with triangular lobe on each side of triangular medial emargination on posterior margin; emargination extending anteriorly ½ length of sternite. Surstylus (in lateral view) boot-like, with 4–6 long setae originating from median knob on posterior surface; distal ⅓ evenly covered in small setulae. Postgonite with distinct apical swelling .......................... R. pilosa sp. nov. – Eye height ~1.5× genal height. Sternite 4 evenly setose ( Fig. 14C ). Sternite 5 with small nipple-like lobe on each side of medial emargination on posterior margin; emargination extending anteriorly almost to base of sternite. Surstylus (in lateral view) strap-like, elongate and narrow; relatively bare except for small scattered setae. Postgonite simple apically, uniformly narrow ................................. .............................................................................................................................. R. newtoni sp. nov. 4. Posterior margin of sternite 5 with elongate, parallel-sided lobes (e.g., Fig. 9C ) on each side of medial emargination; pair of long setulae on margin of desclerotized area adjacent to base of the lobes. Length of M 1 between crossveins dm-cu and r-m <1.4× dm-cu ........................................... 5 – Posterior margin of sternite 5 with an acutely angled lobe on each side of medial emargination (e.g., Fig. 19C ); emargination without long setulae. Length of M 1 between crossveins dm-cu and r-m usually> 1.5× dm-cu ........................................................................................................................ 6 Fig. 7. Phylogeny of species of Rudolfina Roháček, 1987 . Characters and character states refer to those given in Table 1. Tree selected from among 27 equal length trees. Length = 72, Ci = 56, Ri = 58. 5. Second costal sector <0.4× third costal sector. Mid tibia with ventral comb of seta weakly developed, with only 1 strong seta at midlength and 1 long preapical seta. Mid femur with single distinct ventrobasal setae .................................................................................. R. exuberata sp. nov. – Second costal sector ~0.6 × third costal sector. Mid tibia with ventral comb composed of 11–13 setae on apical ½. Mid femur with 4–5 small setae ventrobasally ................................... R. pauca sp. nov. 6. Sternite 5 with small medial triangular lobe ( Marshall & Fitzgerald 1997 : fig. 5). Surstylus strap-like, with base ~1.5 × as wide as distal margin; anterior margin weakly lamellate ( Marshall & Fitzgerald 1997 : fig. 2) ................................................................... R. cavernicola Marshall & Fitzgerald, 1997 – Sternite 5 without medial lobe. Surstylus variable but usually with long posterior lobe and small anterior lobe ...................................................................................................................................... 7 7. Sternite 5 with broad (> ¼ width of sternite) emargination between posterior lobes. Subanal plate complete or incomplete ..................................................................................................................... 8 – Sternite 5 with small (<1/5 width of sternite) emargination between posterior lobes. Subanal plate complete .......................................................................................................................................... 12 8. Second costal sector ~0.35 × third costal sector. Subanal plate narrowly complete ( Fig. 19A ). Sternite 5 posterior margin lateral to posterior lobes straight ( Fig. 19C ). Cercus elongate, small. Surstylus with long, glabrous, oar-like posterior lobe and small rounded anterior lobe with 4–5 long setae on surface .............................................................................................................. R. remiforma sp. nov. – Second costal sector 0.8–1.0 × third costal sector. Subanal plate broadly complete or incomplete. Sternite 5 posterior margin lateral to posterior lobes emarginate (e.g., Fig. 3 A–B). Cercus ovoid, large. Surstylus with posterior lobe variable; anterior lobe complex ............................................... 9 9. Eye small, height ~1.0 × genal height. Length of M 1 between crossveins dm–cu and r-m ~4.0× dmcu. Epandrium swollen, distinctly wider than two preceding abdominal segments ( Fig. 2A ). Subanal plate incomplete. Subepandrial sclerite distinctly arcuate ..................................... R. tumida sp. nov. – Eye larger, height> 1.2× genal height. Length of M 1 between crossveins dm-cu and r-m <2.5× dmcu. Epandrium unmodified, as wide as two preceding abdominal segments. Subanal plate broadly complete. Subepandrial sclerite transverse ..................................................................................... 10 10. Second costal sector equal to third costal sector. Surstylus with posterior lobe elongate, with irregular pectinate anterior surface ( Marshall 1991 : figs 4–5) ................................. R. digitata Marshall, 1991 – Second costal sector <1.0 × third costal sector. Surstylus not as above, with posterior lobe either hoe-shaped or with 3 elongate processes .........................................................................................11 11. Eye height 2.0–2.3× genal height. Mid tibia distinctly arcuate in anterior view. Length of M 1 between crossveins dm-cu and r-m ~1.5× dm-cu. Sternite 5 posterior margin with tips of medial lobes not reaching level of posterior margin adjacent to medial emargination ( Roháček 1985 : fig. 1084). Surstylus with posterior lobe hoe-shaped ( Roháček 1985 : fig. 1085) ................................................. ................................................................................................................ R. rozkosnyi Roháček, 1975 – Eye height ~1.3× genal height. Mid tibia weakly arcuate in anterior view. Length of M 1 between crossveins dm-cu and r-m ~2.0 × dm-cu. Sternite 5 posterior margin with tips of medial lobes extending beyond level of posterior margin adjacent to medial emargination ( Su et al. 2017 : fig. 1F). Posterior lobe of surstylus with 3 elongate projections ( Su et al. 2017 : fig. 1C) ................................ .............................................................................................................................. R. zhangi Su, 2017 12. Posteromedial emargination of sternite 5 with dark margin; emargination deep, extending anteriorly ~1/6 sternite length, and nearly closed posteriorly by inwardly directed lateral lobes ( Fig. 11C ). Epandrium simple, not distinctly wider than preceding abdominal segments. Surstylus with anterior lobe small but well-developed, knob-like; posterior lobe elongate, clavate, with numerous long setae on distal third. Cercus clavate, almost as long as surstylus, projecting ventrally................................ ............................................................................................................................. R. howdeni sp. nov. – Posterior emargination of sternite 5 without dark sclerotized margin; emargination shallow (<1/10 sternite length) and broadly open with short posteriorly projecting lateral lobes ( Figs 8C , 13C ). Epandrium swollen, distinctly wider than preceding abdominal segments. Surstylus with anterior lobe reduced and indistinct; posterior lobe either elongate and narrow ( R. megepandria sp. nov. ) or weakly clavate ( R. bucki sp. nov. ); setae more widely dispersed over apical ½. Cercus either elongate and projecting posteriorly, or small and not distinctly projecting ................................................... 13 13. Sternite 5 with small nipple-like lobes on posterior margin; posterior margin lateral to lobes entire ( Fig. 13C ). Epandrium (in lateral view) with dorsal surface as long as posterior surface; setae below anal opening typical, not elongated. Surstylus with posterior lobe narrow and elongate, weakly constricted on distal ¼, with small rounded swelling near midlength. Cercus elongate, projecting posteriorly. Postgonite apically acute ........................................................... R. megepandria sp. nov. – Sternite 5 with lobes on posterior margin triangular, obtuse; posterior margin lateral to lobes emarginate ( Fig. 8C ). Epandrium (in lateral view) with dorsal surface ~½ length of posterior surface; 4–6 pairs of long cruciate setae adjacent to cercus (usually obscuring cercus in caudal view). Surstylus with posterior lobe weakly clavate, with long thickened seta on posterior margin (near midlength). Cercus obscure, small, indistinct. Postgonite apically truncate ... R. bucki sp. nov. 14. Epiproct tulip-shaped, with narrow anterior elongation broadening near midlength into rounded posterior ‘bulb’ ( Figs 10A , 17A , 20A ). Length of M 1 between crossveins dm-cu and r-m <1.5× dm-cu. Medial portion of tergite 8 small, weakly sclerotized. Cercus shorter than flattened apical seta ................................................................................................................................................... 15 – Epiproct triangular or trapezoidal. Length of M 1 between crossveins dm-cu and r-m> 1.5× dm-cu. Medial portion of tergite 8 distinct, well sclerotized. Cercus as long as or longer than flattened apical seta ................................................................................................................................................... 17 15. Sternite 7 with posterior margin entire. Spermathecae ovoid ( Fig. 20D )......... R. remiforma sp. nov. – Sternite 7 with posterior margin broadly emarginate ( Fig. 10C ). Spermatheca bilobed ................ 16 16. Eye height 2.0× genal height. Second costal sector <0.5× third costal sector .................................. ........................................................................................................................... R. exuberata sp. nov. – Eye height 2.5× genal height. Second costal sector>0.5× third costal sector ....... R. pauca sp. nov. 17. Eye height ~1.5 × genal height. Medial part of tergite 8 posteromedially emarginate ( Fig. 15A ). Epiproct triangular. Spermathecae mushroom-shaped ......................................... R. newtoni sp. nov. – Eye height ≥1.75 × genal height. Medial part of tergite 8 posteriorly entire or desclerotized. Epiproct either trapezoidal or anteriorly rounded. Spermathecae variable .................................................... 18 18. Eye height 2.5× genal height. Length of M 1 between crossveins dm-cu and r-m 3.0× dm-cu. Medial part of tergite 8 elongate, rectangular ( Fig. 4A ) ........................................... R. megepandria sp. nov. – Eye height ≤2.3 × genal height. Length of M 1 between crossveins dm-cu and r-m 2.0× dm-cu. Medial part of tergite 8 variable ...................................................................................................... 19 19. Second costal sector shorter than third costal sector. Epiproct diamond-shaped, with anterolateral margins almost straight ( Fig. 12A )...................................................................... R. howdeni sp. nov. – Second costal sector equal in length to third costal sector. Epiproct with anterolateral margins broadly rounded .............................................................................................................................. 20 20. Medial part of tergite 8 wider than long, with posterior margin weakly emarginate ( Marshall & Fitzgerald 1997 : fig. 5). Epiproct triangular .................. R. cavernicola Marshall & Fitzgerald, 1997 – Medial part of tergite 8 as long as or longer than wide; posterior margin entire. Epiproct diamondshaped .............................................................................................................................................. 21 21. Medial part of tergite 8 longer than wide ( Marshall 1991 : fig. 1). Epiproct with surface even, smooth; anterior margin broadly rounded .............................................................. R. digitata Marshall, 1991 – Medial part of tergite 8 as long as wide ( Roháček 1985 : fig. 1079). Epiproct with surface wrinkled on posterior half; anterior margin weakly trilobed ................................. R. rozkosnyi Roháček, 1975