Posteroventral Margin Research Articles

A new deep-sea species of genus Bathypisella (Crustacea: Peracarida: Amphipoda) from bathyal soft bottoms, south-western Gulf of Mexico

ABSTRACT A new deep-sea species of the genus Bathypisella was collected from bathyal soft bottoms, SW Gulf of Mexico. This new species represents the second Bathypisella species known worldwide, which is characterised by head subequal in length to pereonal segments 1–2 combined, eyes absent, toothed pleonal and urosomal segments, 4-articulate accessory flagellum, coxae 1–4 posteroventral area slightly notched; coxa 4 posterior lobe absent, maxilliped palp article 3 in right angle, maxilla 1 inner plate with five lateral setae, left mandible with three teeth on lacinia mobilis, gnathopod 1 palmar margin convex, gnathopod 2 propodus palmar margin concave, one long, robust seta in palmar angle, epimeron 3 with trifid posteroventral margin, and telson cleft half its length. Besides a complete description of the new species, a dichotomous key to identify both Bathypisella species is provided. http://www.zoobank.org/urn:lsid:zoobank.org:pub:73A22DCA-2692-4C24-B008-E01F8E130B69

Description of a new species of the genus Cultellus Schumacher, 1817 (Bivalvia, Pharidae) from the South China Sea, based on integrative taxonomy

The present study describes a new species within the genus Cultellus Schumacher, 1817 collected from the South China Sea. An integrative taxonomic approach incorporating morphological comparisons, geometric morphometrics and genetic analyses was used to identify and differentiate the new species. Cultellus exilissp. nov. is distinguished from its congeners by its slender, fragile and translucent valves, curved posteroventral margins and relatively large protractor scars. The geometric morphometric analyses, based on outlines data, indicated that samples of Cultellus exilissp. nov. clustered together and were distinctly separated from other species. Multiple species delimitation results, based on the mitochondrial COI gene, support the separation of Cultellus exilissp. nov. from its related congeners. Phylogenetic analyses of a nuclear (28S rRNA) and two mitochondrial (COI, 16S rRNA) genes using Maximum Likelihood and Bayesian Inference methods revealed that the species belongs to the genus Cultellus. The superfamily Solenoidea Lamarck, 1809, which includes the families Solenidae Lamarck, 1809 and Pharidae H. Adams & A. Adams, 1856, exhibits closer affinity to the family Hiatellidae Gray, 1824 than to Solecurtidae d’Orbigny, 1846. Furthermore, we found that the genus Siliqua was clustered alongside the genera Ensiculus and Phaxas as a sister clade, which contradicts the current systematics of the subfamily within the family Pharidae. This work highlights the utility of integrative taxonomy for species identification, recognition and phylogenetic investigation.

Ooceraeahainingensis sp. nov.: A new Chinese Ooceraea (Hymenoptera, Formicidae, Dorylinae) species with a dealate queen, closely allied to the queenless clonal raider ant O.biroi.

The clonal raider ant, Ooceraeabiroi, is a queenless species that reproduces asexually, and these traits make it an attractive model system for laboratory research. However, it is unclear where on the ant phylogeny these traits evolved, partly because few closely related species have been described and studied. Here, we describe a new raider ant species, Ooceraeahainingensis sp. nov., from Zhejiang, China. This species is closely related to O.biroi but can be distinguished by the following features: 1) workers of O.hainingensis sp. nov. have an obvious promesonotal suture and a metanotal groove, whereas these characters are ambiguous in O.biroi; and 2) the subpetiolar process of O.hainingensis is prominent and anteroventrally directed like a thumb with sublinear posteroventral margin, while in O.biroi, it is anteroventrally directed but slightly backward-bent. Molecular phylogenetic analyses confirm that O.hainingensis is genetically distinct from O.biroi. Importantly, unlike O.biroi, O.hainingensis has a queen caste with wings and well-developed eyes. This suggests that the loss of the queen caste and transition to asexual reproduction by workers is specific to O.biroi and occurred after that species diverged from closely related congeneric species.

Every Single Specimen Counts: A New Docosia Winnertz (Diptera: Mycetophilidae) Species Described from a Singleton.

Simple SummaryA new fungus gnat species has been described from a single specimen collected from Georgia (Sakartvelo). The new species, named after its occurrence in Caucasia as Docosia caucasica sp. n., is distinguished from congeners by the characters in male terminalia and a unique COI sequence. As a substantial proportion of species in ecological communities tend to be rare, about 20–30% of new insect taxa have been described from a singleton so far. Therefore, following high-quality standards when describing new species, particularly when dealing with minimalistic material, is crucial. As much as possible, using multiple sets of characters, like morphology and DNA sequencing, is encouraged.A new species—Docosia caucasica sp. n.—has been described from material collected from the Lesser Caucasus Mountains in Georgia (Sakartvelo). The new species belongs to a group of Palaearctic species characterized by distinct posterolateral processes of gonocoxites and apically modified setae at the posteroventral margin of the gonocoxites medially. Within the group, D. caucasica sp. n. is most similar to D. landrocki Laštovka and Ševčík, 2006 in having a similar outline of the medial process of posteroventral margin of the gonocoxites and the gonostylus. There is also a marked difference within the partial cytochrome c oxidase subunit 1 gene (COI) sequence of D. caucasica sp. n. and other Docosia spp. available in public databases. As the new species is described from a single male specimen only, the adequacy and code compliance of that are discussed.

Presumptive stridulatory organs inParanthuracf.japonicaRichardson, 1909 (Isopoda: Cymothoida: Paranthuridae)

AbstractMorphological diversity of sound-producing structures has not been well investigated among members of superorder Peracarida. Presumptive stridulatory sound-producing organs have been reported in some amphipods and tanaidaceans, and sound production by these organs has been documented in two isopod species in Oniscidea and Sphaeromatidea. We describe three presumptive stridulatory organs in the paranthurid isopod Paranthura cf. japonica Richardson, 1909, the first case known in Cymothoida. One type, consisting of a scale-bearing knob on the posterolateral corner of a pereonite and the scale-bearing anterolateral corner of the succeeding pereonite, was found between two pairs of pereonites (1, 2 and 2, 3). A second type involves a serrated structure in the sub-posterolateral region of pereonites 1 and 2, with the sharp anterolateral margins of pereonites 2 and 3 appearing to provide corresponding plectra. The third type involves an extension bearing a pair of serrated structures on the posteroventral margin of pereonites 1 and 2; the anterior-ventrolateral edges of pereonites 2 and 3 appear to provide corresponding plectra. All three organs occurred in both sexes of P. cf. japonica. Our discovery of novel, presumptive stridulatory organs in an intertidal isopod indicates that much remains to be learned about the biology of even common peracarid species.

Species of the Maera-clade collected from Japan. Part 4: addenda to genera Maera Leach, 1814 and Quadrimaera Krapp-Schickel Ruffo, 2000, with revised keys to Japanese species of the clade (Crustacea: Amphipoda: Maeridae).

Two new species of Maera Leach, 1814 and Quadrimaera Krapp-Schickel Ruffo, 2000 included in the Maera-clade are described from Japan. Maera denticoxa sp. nov. was collected from Iwate and Hokkaido Prefectures and can be distinguished from its congeners by the small notches on the posteroventral margins of coxae 1-6. Quadrimaera angulata sp. nov. from north of Tanegashima Island in Kagoshima Prefecture is characterized by the distal tooth on the mandibular palp article 1, the rounded palm of the female gnathopod 2, and the angular posterodistal margin of the pereopod 7 basis. Keys to Japanese species of the Maera-clade are provided. In total, seventeen species included in the clade occur in Japan.

Five new subterranean amphipods of the genus Pseudocrangonyx from Korea (Crustacea, Amphipoda, Pseudocrangonyctidae).

Although the majority of the species belonging to the genus Pseudocrangonyx Akatsuka & Komai, 1922 are found among the subterranean fauna of eastern Asia, the taxonomic knowledge is very poor and only four species have been recorded in Korea. In this study, the morphology of the stygobitic pseudocrangonyctid amphipods from Korean subterranean waters was examined and five new species were identified: Pseudocrangonyx concavussp. nov. has a characteristic emarginated posteroventral margin of epimeral plate 3; Pseudocrangonyx gracilipessp. nov. differs from other pseudocrangonyctids by the slender and elongated pereopods and more produced posterodistal corner of epimeral plate 3. Pseudocrangonyx crassussp. nov. shows the expanded peduncular articles and a reduced flagellum of antenna 2. Pseudocrangonyx minutussp. nov. is distinguished by more reduced pleopod articles compare to other pseudocrangonyctids. Pseudocrangonyx villosussp. nov. has the more setose bases of pereopods 3 and 4. Detailed descriptions and illustrations are presented for these five new species.

Redescription, paleogeography, and experimental paleoecology of the Silurian phyllocaridGonatocaris

AbstractGonatocaris decora(Clarke, 1901) is an unusual, highly ornamented Silurian phyllocarid from the Pittsford Shale Member of the Vernon Formation, Salina Group of New York, that has been allied withEmmelezoein the past due to the possession of an ‘optic tubercle.’ The systematic positions ofGonatocarisandEmmelezoehave been difficult to assess due to the lack of complete remains, attributions based on spurious characters, and missing and unfigured specimens. Relatively recent collections ofGonatocaris decora, along with a relocation of the original type material ofEmmelezoe, have allowed a reexamination of all relevant genera and a more robust systematic placement forG. decora. Characters of generic importance forGonatocarisinclude a greatly elongated abdomen; an acute angle of the ventral carapace margin separating distinct anteroventral and posteroventral margins from each other; and distinctive, multiscale horizontal ridge-like ornament of the carapace valves. Growth was found to be isometric. Experimental work done using a model of the scale-like ornament and multiple grain sizes of substrate indicates that cuticle ornament may have served to increase friction between the animal and a fine sand substrate, although resistance to predation is the currently favored hypothesis. BecauseGonatocarisspecies are currently known only from the eastern margin of Laurentia and northern South China, it is likely that this genus was nektonic. Accumulations of similarly sized carapaces and other disarticulated sclerites in shallow-water settings may indicate spawning events following molting en masse.

<em>Atlantiphoxus wajapi</em> n. gen., n. sp. (Crustacea: Amphipoda: Phoxocephalidae), a new deep-sea amphipod from the southwestern Atlantic

A new genus and species of the family Phoxocephalidae is here described with material collected during the Mini Biological Trawl Project at 224 and 500 m depth off Brazil’s southeastern coast in the states of Rio de Janeiro and São Paulo. Atlantiphoxus wajapi n. gen., n. sp. can be grouped in the subfamily Phoxocephalinae and seems to be morphologically close to Fuegiphoxus Barnard and Barnard, 1980 and Parharpinia Stebbing, 1899. However it can be easily distinguished within the phoxocephalids by the following characters: deep pereonites with small coxae; rostrum unconstricted; eyes absent; man­dible molar not triturative, but as a small hump with 3 multicuspidate stout setae; pereopods 3-4 with stout dactylus; pereopod 5 basis strongly tapering distally; pereopod 7 basis anterodistal corner with a row of long plumose setae; dactylus elongate. Epimeral plate 3 posteroventral margin strongly produced.

A new cypridopsine genus (Crustacea, Ostracoda) from Thailand

A new cypridopsine genus, Cyprettadopsis gen. nov., described here, is principally characterized by the reduced caudal ramus, the strongly serrated claw G2 of the antenna (A2), the A2 subquadrate terminal segment, the undivided penultimate segment of the second thoracopod (T2), the morphology of the third thoracopod bearing a distinctly separated terminal segment, the complete septa on the posteroventral margin and the incomplete septa on the anterior margin of both valves. Based on a combination of these characters, a new tribe, Cyprettadopsini trib. nov., is created in the subfamily Cypridopsinae Kaufmann, 1900 to accommodate this new genus, and one new species, Cyprettadopsis sutura gen. et sp. nov., is described as the type species. Apart from the above generic characters, the following features are also typical of the new species: the tiny needlepoint-like pores along the anterior and ventral margins of both valves, the remarkably large β-seta on the mandibular palp and the considerably short d2 seta on the T2. The presence of marginal septa in the new genus is a distinctive character and constitutes the first record of this feature within Cypridopsinae. The taxonomically relevant characters in the new taxon and related taxa are briefly discussed.

Worm-riding clam: description of Montacutona sigalionidcola sp. nov. (Bivalvia:Heterodonta: Galeommatidae) from Japan and its phylogenetic position.

A new galeommatid bivalve, Montacutona sigalionidcola sp. nov., is described from an intertidal flat in the southern end of the Kii Peninsula, Honshu Island, Japan. Unlike other members of the genus, this species is a commensal with the burrowing scale worm Pelogenia zeylanica (Willey) (Annelida: Sigalionidae) that lives in fine sand sediments. Specimens were always found attached to the dorsal surface of the anterior end of the host body. This species has a ligament lithodesma between diverging hinge teeth, which is characteristic of Montacutona Yamamoto Habe. However, it is morphologically distinguished from the other members of this genus in having elongate-oval shells with small gape at the posteroventral margin and lacking an outer demibranch. Molecular phylogenetic analysis based on the four-gene combined dataset (18S + 28S + H3 + COI) indicated that this species is monophyletic with Montacutona, Nipponomontacuta Yamamoto Habe and Koreamya Lützen, Hong Yamashita, which are commensals with sea anemones or Lingula brachiopods. This result suggests that host shifting across different phyla occurred at least twice in this clade.

Two new species of Cypretta Vávra, 1895 (Crustacea, Ostracoda) from Thailand and discussion of genus.

Two Cypretta species from Thailand are described: Cypretta aculeata n. sp. and Cypretta triangulata n. sp. Cypretta aculeata n. sp. can be characterized chiefly by the valve surface equipped with long setae, spine-like bristle and distinctive pits, the presence of tubercles on postero-ventral margin of the internal left valve and the denticulated ridge on the postero-ventral part of the internal right valve, the long d1 seta on the second thoracopod (T2), and the long Sp seta on the caudal ramus (CR). Based on the valve surface ornamentation, C. aculeata n. sp. is similar to C. globosa (Brady, 1886), C. intonsa Furtos, 1936, C. spinosa Cohuo-Durán et al., 2013 and C. vivacis Würdig Pinto 1993. A key to the species within this group is thus provided. The main diagnostic features of Cypretta triangulata n. sp. are the triangular carapace in the dorsal view, the absence of tubercles on the postero-ventral margin of the internal left valve, the presence of denticulated ridge on the postero-ventral part of the internal right valve, the short d1 seta on T2 and the long Sp seta on the CR. The diagnostic characters for the species identification of the genus Cypretta are briefly discussed with regard to the morphology and number of the septa and lunules, the traits of the internal side of the valves, the features of soft body parts (such as the mandible, the thoracopods and the CR) and the morphological aspects of the hemipenis.

Aroui minusetosus, a new species of Scopelocheiridae from Korea (Crustacea, Amphipoda, Lysianassoidea)

A new species, Aroui minusetosus sp. n., is recorded from Korean waters with detailed description and illustrations. A new key to all known Aroui is provided. The Korean material of this scopelocheirid is readily assigned to the genus Aroui by the presence of long and distally barbed setae on the outer plate of maxilla 2. This new species is distinguished from congeners by ventrally smooth coxae 1-3 and a setose posteroventral margin of coxa 4, the subchelate gnathopod 2 having a row of four robust setae on its posterior margin (including an elongate single locking seta), and the setation of all appendages which is less dense than in other species. This is the first record of scopelocheirid amphipods from Korean waters.

Osteology of Galeamopus pabsti sp. nov. (Sauropoda: Diplodocidae), with implications for neurocentral closure timing, and the cervico-dorsal transition in diplodocids.

Diplodocids are among the best known sauropod dinosaurs. Numerous specimens of currently 15 accepted species belonging to ten genera have been reported from the Late Jurassic to Early Cretaceous of North and South America, Europe, and Africa. The highest diversity is known from the Upper Jurassic Morrison Formation of the western United States: a recent review recognized 12 valid, named species, and possibly three additional, yet unnamed ones. One of these is herein described in detail and referred to the genus Galeamopus. The holotype specimen of Galeamopus pabsti sp. nov., SMA 0011, is represented by material from all body parts but the tail, and was found at the Howe-Scott Quarry in the northern Bighorn Basin in Wyoming, USA. Autapomorphic features of the new species include a horizontal canal on the maxilla that connects the posterior margin of the preantorbital and the ventral margin of the antorbital fenestrae, a vertical midline groove marking the sagittal nuchal crest, the presence of a large foramen connecting the postzygapophyseal centrodiapophyseal fossa and the spinopostzygapophyseal fossa of mid- and posterior cervical vertebrae, a very robust humerus, a laterally placed, rugose tubercle on the concave proximal portion of the anterior surface of the humerus, a relatively stout radius, the absence of a distinct ambiens process on the pubis, and a distinctly concave posteroventral margin of the ascending process of the astragalus. In addition to the holotype specimen SMA 0011, the skull USNM 2673 can also be referred to Galeamopus pabsti. Histology shows that the type specimen SMA 0011 is sexually mature, although neurocentral closure was not completed at the time of death. Because SMA 0011 has highly pneumatized cervical vertebrae, the development of the lamination appears a more important indicator for individual age than neurocentral fusion patterns. SMA 0011 is one of very few sauropod specimens that preserves the cervico-dorsal transition in both vertebrae and ribs. The association of ribs with their respective vertebrae shows that the transition between cervical and dorsal vertebrae is significantly different in Galeamopus pabsti than in Diplodocus carnegii or Apatosaurus louisae, being represented by a considerable shortening of the centra from the last cervical to the first dorsal vertebra. Diplodocids show a surprisingly high diversity in the Morrison Formation. This can possibly be explained by a combination of geographical and temporal segregation, and niche partitioning.

Taxonomic revision of the genus Atopomesus Myers, 1927 (Characiformes: Characidae), with comments on its phylogenetic relationships

The monotypic genus Atopomesus, a poorly known member of the family Characidae, is re-described. Atopomesus pachyodus is endemic to the Rio Negro basin, where it feeds on aquatic insect larvae, and seems to occur mostly in riverine sand banks and beaches. A. pachyodus was originally described as a member of the Characidae subfamily Cheirodontinae, but has been considered as an Characidae incertae sedis based on relatively superficial studies of its dentition and external morphology. However, according to the morphological analyses presented herein, a close relationship between A. pachyodus and the members the subfamily Aphyoditeinae is hypothesized. The inclusion of A. pachyodus in the Aphyoditeinae is based on the shared presence of a long posteriorly directed spiniform process on the posteroventral margin of the orbitosphenoid, the elongation of the transverse process of the neural arch of the third vertebra, and the elongation of the posterior process of the parasphenoid.

Two new species of the Rhyacophila anatina Species Group from China (Trichoptera: Rhyacophilidae).

Two new species of the Rhyacophila anatina Species Group, R. coalita n. sp. and R. bicaudata n. sp. are described, diagnosed and illustrated. Rhyacophila coalita n. sp. is somewhat similar to R. yipung Schmid and R. elongata Kimmins in the male genitalia, but can be distinguished from them by the deep incision at the apex of the dorsal process of the aedeagus, fused anal sclerites, and a pair of membranous bulbs at the middle of the aedeagus. Rhyacophila bicaudata n. sp. is similar to R. triangularis Schmid in male genitalia, but can be diagnosed by the longer preanal appendages, the slightly incised posteroventral margins of preanal appendages, and a gradually narrowed apicodorsal lobe of segment IX.

Pectoral girdle bones in eurypterygian fishes

Bones of the pectoral girdle skeleton in representatives of 48 genera in 41 families of eurypterygian fishes were studied. The structure and position of the pectoral girdle is relatively stable in eurypterygians. It consists of the extrascapula, posttemporal, supracleithrum, cleithrum, postcleithrum, scapula, coracoid, actinosts, and fin rays. An ectocoracoid is present in some Gasterosteiformes. Most eurypterygians have a posttemporal with distinct dorsal and ventromedial processes. The dorsal process ligamentously articulates with the epioccipital and the ventromedial process with the intercalary when present, and when absent, with the posteroventral margins of the pterotic and exoccipital. In most taxa, the supracleithrum bears a sensory canal and articulates with the posttemporal anteriorly and with the cleithrum posteriorly. The cleithrum is Y-shaped consisting of the anterodorsal, posterodorsal, and ventral rami. Dorsal and ventral postcleithra are present in some Eurypterygii. The scapula articulates with the cleithrum and bears a foramen which is complete or open anteriorly and bordered by the cleithral ventral ramus. Most taxa have four autogenous actinosts that increase in size gradually from the first to the fourth, but in some, the first actinost is fused. The dorsalmost ray is rudimentary in some taxa.

New material of Natchitochia jonesi and a comparison of the innominata and locomotor capabilities of Protocetidae

AbstractNew material of Natchitochia from the Bartonian Archusa Marl Member is described here, including thoracic, lumbar, sacral, and caudal vertebrae, an innominate, proximal femur, and pedal? phalanx. The vertebrae and innominate are similar to those of Qaisracetus and Georgiacetus. The structure of the caudal vertebrae support previous observations that as sacral vertebrae disconnect from the sacrum, they become caudalized, developing hemal processes on the posteroventral margins of the bodies, reminiscent of chevron bones associated with true caudal vertebrae. The innominate of Natchitochia shares an elongate ilium and pubis with Qaisracetus and Georgiacetus, which differ from the innominata of the more apomorphic archaeocetes. Comparison of archaeocete innominata and sacra in a phylogenetic context indicates that the apomorphic sacrum composed of 4 vertebrae (Pakicetus, Ambulocetus, Rodhocetus, Maiacetus) was reduced to 3 (Qaisracetus) to 2 (Protocetus?, Natchitochia) to 0 (Georgiacetus, Basilosauridae), while the innominata remained robust, supporting a large hind limb until the origin of the Basilosauridae. In Georgiacetus, the innominate is large but detached from the vertebral column, preventing the use of the hind limb in terrestrial locomotion. More crownward cetaceans for which the innominate is known display greatly reduced innominata and hind limbs are disconnected from the vertebral column.

Description of a new shrew of the genus Cryptotis (Mammalia: Soricomorpha: Soricidae) from the Sierra de Aroa, an isolated mountain range in northwestern Venezuela, with remarks on biogeography and conservation

In South America, shrews of the genus Cryptotis have a primarily Andean distribution. Based on specimens from the non-Andean Sierra de Aroa in Venezuela, we name Cryptotis aroensis sp. nov., which we assign to the C. thomasi group of thegenus owing to its possession of characters that include a relatively large body size, luxuriant fur, moderately enlargedforefeet with elongated and narrow claws, unicuspid teeth relatively narrow and concave on the posteroventral margin,ectoloph of first upper molar with the anterior element reduced relatively to the posterior element, and mandible with thearticular process not robust, high, and broad, and with the coronoid process joining the ramus at a low angle. The newspecies can be differentiated from other members of the C. thomasi group on the basis of its possession of a uniquecombination of characters, that include a rich grayish brown pelage, a narrow palate at the level of the second upper molars(no overlap in this measurement observed with 146 specimens of 10 other species of the group), nasal cavity and ethmo-turbinals partially visible in occlusal view of palate, lacrimal foramina wide and deep, tympanic process of petromastoidsshowing a minute foramen, unicuspid teeth with posterolingual cuspules, fourth unicuspid tooth labially placed, thirdupper molar complex and nearly as wide as the second upper molar, and bicuspulate lower incisors. The new species isknown from only 3 specimens obtained at the type locality, which is in a pristine patch of cloud forest at elevation 1730m, and represents the first mammalian taxon known to be endemic to the Sierra de Aroa, a small and isolated mountainrange that was previously reported to possess numerous biotic elements that are either exclusive, or shared with the muchlarger Cordillera de la Costa to the east. The clear morphological differentiation of the new species with respect to itsAndean relatives suggests that its ancestors colonized the Sierra de Aroa several glacial maxima ago, when montanevegetation belts were lower than today. The presumably optimal habitat of the new species (cloud forests of the Sierra deAroa above 1500 m) covers less than 40 km2 , and is threatened by deforestation and global climate change. Therefore, thenew species can be categorized as endangered by application of criteria B2a and E of the current “Red List Categories and Criteria” of the International Union for Conservation of Nature.

Two new species ofMetaleptobasisfrom Central Ecuador (Odonata: Coenagrionidae)

Two new species of Metaleptobasis from Ecuador are described and illustrated. Metaleptobasis gibbosa (holotype ♂, allotype \female: Ecuador, Pastaza Province, forest wetlands, Los Copales, between Mera and Shell, 01° 29′ 30′′ S, 078° 04′ 19′′ W, elevation 1070 m, 20–22 September 2005, leg. K. J. Tennessen; deposited in Florida State Collection of Arthropods) appears related to M. mauffrayi based on large, scythe-shaped posterior hamules; it differs by having cerci about 0.8 times the length of paraprocts, paraprocts wide in proximal half and posterior margin of S10 straight in dorsal view; the female has small denticles on the posteroventral margin of S8 but lacks a distinct vulvar spine. Metaleptobasis knopfi (holotype ♂, allotype \female: Ecuador, Sucumbios Province, swamp-forest and stream, 52 km NE of Chaco, 00° 00′ 04′′ S 077° 24′ 07′′ W, elevation 685 m, 18 August 1980, leg. K. W. Knopf; deposited in Florida State Collection of Arthropods) appears related to M. minteri based on color pattern, small ...