Gonopod Structure Research Articles

A revision of the millipede family Paracortinidae (Diplopoda, Callipodida).

The taxonomy of the family Paracortinidae Wang & Zhang, 1993 is revised based on literature, old and recently collected material. A new genus Crassipetalum Akkari & Stoev, gen. nov. is described, to accommodate a new species Crassipetalummagnum Akkari & Stoev, gen. nov. et sp. nov. and a recently described species Crassipetaluminflatum (Chen, Zheng & Jian, 2023), comb. nov. The genus Scotopetalum Shear, 2000 hitherto described for the Vietnamese species S.warreni Shear, 2000 and subsequently synonymised with the genus Paracortina Wang & Zhang, 1993 is here resurrected and supplemented with another species, S.chinensis (Stoev & Geoffroy, 2004), comb. nov., ex Paracortinachinensis Stoev & Geoffroy, 2004. The status of the fourth genus in the family, Angulifemur Zhang, 1997, is reconfirmed. Based on recently collected specimens from China, two new species of the genus Paracortina are described: P.asciformis Akkari & Stoev, sp. nov. (Sichuan Prov., Lixian County) and P.kabaki Akkari & Stoev, sp. nov. (Yunnan, Shangrila County). The Vietnamese species Paracortinamultisegmentata Stoev & Geoffroy, 2004 and Paracortinakyrang Nguyen, Stoev, Nguyen & Vu, 2023 are considered of uncertain taxonomic position within Paracortinidae. Differential diagnoses for the proposed genera as well as for all the species are presented, and descriptions or descriptive notes for all the species are provided, using a standardised terminology, and when possible, accompanied by micrographs of the habitus and gonopod structures. An identification key based on gonopod structures is proposed for all the members of the family. A discussion on species affinities, secondary sexual characters, troglomorphic characters, geographical distribution, and habitat preferences are also provided together with a distribution map for all members of the family.

Two new species of hairy crabs (Pilumnidae) and the first record of Crinitocinus alcocki (Borradaile, 1900) (Acidopsidae) (Crustacea: Brachyura) from Taiwan.

Two new species of pilumnid crabs, Heteropilumnus planus n. sp. and Pseudolitochira taiwang n. sp., are described from reefs in Taiwan. Heteropilumnus planus n. sp. is most similar to H. hirsutior (Lanchester, 1900) from Singapore and Japan, but can easily be distinguished by its distinctly flatter carapace, different anterolateral carapace armature, longer ambulatory legs, and male first gonopod structure. Pseudolitochira taiwang n. sp. is most similar to P. crinita Ng & Clark, 2022, from Papua New Guinea but can easily be separated by its carapace physiognomy, armature of the anterolateral carapace margin and proportionately shorter ambulatory legs. Heteropilumnus setosus (A. Milne-Edwards, 1873) is also transferred to Pseudolitochira; and compared with P. taiwang n. sp. The rarely reported acidopsid, Crinitocinus alcocki (Borradaile, 1900) is also recorded from Taiwan for the first time, substantially extending its known range northwards.

Ommatoiulus ktarii, a new millipede from Tunisia and considerations on the taxonomy of the genus (Diplopoda, Julida, Julidae)

A new millipede, Ommatoiulus ktarii sp. nov., is here described from Tunisia based on relatively recently collected specimens from the semi-arid area of the plain of Oueslatia. A description of the external morphology and gonopod structures are provided, proving the new species to be most similar to the only hitherto known schizophyllinine from Libya, Ommatoiulus rimosus (Karsch, 1881) described more than 140 years ago. Photographs of the gonopods of all Tunisian Ommatoiulus Latzel, 1884 species are provided.

Tuerkayana latens, a New Species of Land Crab from French Polynesia, with a Discussion on the Phylogeny of the Genus (Crustacea: Decapoda: Brachyura: Gecarcinidae).

The taxonomy of the gecarcinid land crab Tuerkayana rotundum (Quoy & Gaimard, 1824) is revised. The taxon, the type species of the genus, occurs from the western Indian Ocean to the western Pacific, and varies substantially in colour and various morphological features, but the male first gonopod structure is constant and the extensive genetic data from mitochondrial 16S rDNA, cytochrome c oxidase subunit 1 and control region markers confirms the recognition of one wide-ranging species. Specimens from Tuamotu in French Polynesia and Pitcairn Island, however, differ in having a smoother and slightly more swollen carapace, and significantly, the male first gonopod structure is distinctly different. The genetic data also supports their differentiation. As such, this material is here recognised as a new species, Tuerkayana latens n. sp.

A new species of the hitherto monospecific genus Pleonoporus Attems, 1938 (Diplopoda, Spirostreptida, Odontopygidae).

The hitherto monospecific genus Pleonoporus is revised based on the syntypes of P.robustus Attems, 1938, housed in Naturhistorisches Museum Wien (NHMW), as well as on specimens of what we interpret as a new species of the genus, Pleonoporustanzanicus sp. nov., collected in Tanzania and housed in the Museum of Nature - Zoology, Leibnitz Institute for the Analysis of Biodiversity Change (ZMH) for more than a century. Both species are described based on habitus and gonopod structures and illustrated with micrographs, whereas scanning electron microscope images are also provided for the new species. This paper further highlights the importance of natural history collections for taxonomic research and studies on species diversity in general.

Is a prominent sternite related to spine length, spine number, copulation duration, and male width in Centrobolus Cook, 1897?

Four species of Centrobolus were identified (C. fulgidus, C. anulatus, C. inscriptus, C. ruber) based on morphology and confirmed using Scanning Electron Microscopy (SEM) of Gonopod structure. Two sets of linear measurements were made from the SEM micrographs: (1) prominence of the stemite, and (2) length of the spines present on the distal knob (which were counted). Copulation duration and male width were recorded. Sternite prominence and spine length were positively related (Kendall's τ=1, Z score=2.32, n=3, p=0.01). Sternite prominence and spine number were inversely related (Kendall's τ=-1, Z score=-2.32, n=3, p=0.01). Spine length and spine number were inversely correlated (Kendall's τ=-1, Z score=-2.32, n=3, p=0.01). There was a significant correlation between sternite prominence and copulation duration in the four species (Pearson's r=0.97, Z score=2.14, n=4, p=0.02). Sternite prominence was positively related to male width (r=0.96, Z score=1.90, n=4, p=0.03). This supports the function of the sternite as (hypoallometric) devices adapted toward sperm competition.

Geosesarma sodalis, a new species of vampire crab (Crustacea, Brachyura, Sesarmidae) from a limestone cave in central Sarawak, Malaysia.

A new species of semi-terrestrial crab of the genus Geosesarma (Sesarmidae) is described from a limestone cave in central Sarawak, Malaysian Borneo. Geosesarma sodalissp. nov. is characterised by its quadrate carapace, absence of a flagellum on the exopod of the third maxilliped, presence of 10 or 11 sharp tubercles on the dactylus of the chela and a diagnostic male first gonopod structure. This is the sixth species of Geosesarma reported from Sarawak, and the first member of the genus collected from inside caves.

Two new species of freshwater crabs of the genera Eosamon Yeo & Ng, 2007 and Indochinamon Yeo & Ng, 2007 (Crustacea, Brachyura, Potamidae) from southern Yunnan, China.

Two new species of potamid crabs, Eosamon daiaesp. nov. and Indochinamon malipoensesp. nov. are described from the Sino-Burmese border, southwestern Yunnan and from the Sino-Vietnamese border, southeastern Yunnan, China. The two new species can be distinguished from their closest congeners by several characters, among which is the form of the first gonopod structures. Molecular analyses based on partial mitochondrial 16S rDNA sequences also support the systematic status of these new taxa.

Haasea Verhoeff, 1895—a genus of tumultuous history and chaotic records—redefinition, revision of taxonomy and geographic distributions, with descriptions of two new species from Austria and Serbia (Diplopoda, Chordeumatida, Haaseidae)

In this paper we revise the chordeumatidan genus Haasea Verhoeff, 1895 for the first time and describe two new species viz., H. gruberi sp. nov. and H. makarovi sp. nov. discovered in Austria and Serbia, respectively. A new terminology is proposed to standardize the description of the gonopod structures in the genus. Type material obtained from several institutions was examined and documented herein, whereby lectotypes are designated. We clarified the taxonomic status of a few taxa and consider the species H. norica (Verhoeff, 1913) and H. guidononveilleri Makarov, 2008 as a junior subjective synonyms of H. cyanopida (Attems, 1903) and H. vidinensis (Strasser, 1973a), respectively. The following subspecies or varieties, viz., Orobainosoma filicis ossiacum Verhoeff, 1939b, Orobainosoma flavescens vornatscheri Verhoeff, 1935, Orobainosoma hungaricum orientale Tabacaru, 1965, and Orobainosoma inflatum var. aspidiorum Verhoeff, 1929 are here regarded as junior subjective synonyms of their nominal taxa. The taxonomic relationships within the genus Haasea are discussed and an identification key to its 17 species is presented, based on number of body segments and gonopod structures. Maps showing species occurences based on historical and recent records are presented to understand their respective geographic ranges. H. flavescens is now deleted from the list of species in Croatia, Bosnia and Herzegovina, Slovenia and Italy as these records were based on misidentified material. H. inflata is deleted from the fauna of Bosnia and Herzegovina, whereas H. hungarica is newly recorded from Austria, Serbia and Slovenia.

Deep-sea spider crabs of the family Epialtidae MacLeay, 1838, from Papuabr />New Guinea, with a redefinition of Tunepugettia Ng, Komai amp; Sato, 2017, anddescriptions of two new genera (Crustacea: Decapoda: Brachyura: Majoidea).

The deep-water epialtid spider crab (superfamily Majoidea) material collected from recent French expeditions to Papua New Guinea (BIOPAPUA 2010, PAPUA NIUGINI 2012, MADEEP 2014, and KAVIENG 2014) was studied. In addition to several new records for the country, five new species of Oxypleurodon Miers, 1885, Rochinia A. Milne-Edwards, 1875, and Tunepugettia Ng, Komai Sato, 2017, are described. The taxonomy of Tunepugettia is reappraised, and a new genus, Crocydocinus n. gen., is established, characterised by its smooth ambulatory legs and a distinct male first gonopod structure. Four species from the Bay of Bengal, Sumatra, and Réunion Island, currently placed in Rochinia and Tunepugettia are transferred to Crocydocinus n. gen. and four new species from Papua New Guinea, Philippines, and Vanuatu are described. A new genus, Neophrys n. gen., with one new species from Papua New Guinea, is established, and is characterised by the supraorbital eave being fused with the carapace and the poorly developed pre-orbital angle.

Taxonomy of the thelyphonid genus Typopeltis Pocock, 1894, including homology proposals for the male gonopod structures (Arachnida, Thelyphonida, Typopeltinae).

The genus Typopeltis Pocock, 1894 is poorly known regarding its systematics, natural history, and distribution, despite important taxonomic advances during the 1990s. Currently, only 13 species are known from East Asia, including areas in south China, Japan, Vietnam, Laos, Thailand, and Taiwan. In this work, we describe and illustrate a new species of Typopeltis from Vietnam and provide a new description for the male of T.guangxiensis Haupt & Song, 1996. Additionally, we describe and illustrate the female gonopod of T.guangxiensis for the first time and propose a new homology hypothesis for the male gonopod parts. The male of T.laurentianussp. n. is characterized by the unique patellar apophysis that presents a smooth texture and no spines. Typopeltislaurentianussp. n. is the third species of this genus to be described from Vietnam.

Redescripción de <i>Percnon pascuensis</i> (Brachyura, Grapsoidea, Percnidae) de Rapa Nui

Percnon pascuensis is redescribed based on adult specimens collected in Easter Island (today Rapa-Nui). The gonopod (first two pair of pleopod of males) structure is described by first time and compare with the other species of the genus. The analysis conclude that P. pascuensis is closely to P. sinensis based on the gonopods morphology. P. sinensis is distributed to China Sea. Earlier papers claim that P. pascuensis is closely related with P. planissimum, a widely distributed species, but both species are different morphology of the gonopods. P. pascuensis is a valid species seemingly endemic of the Easter Island.

A mountain of millipedes VII: The genus Eviulisoma Silvestri, 1910, in the Udzungwa Mountains, Tanzania, and related species from other Eastern Arc Mountains. With notes on Eoseviulisoma Brolemann, 1920, and Suohelisoma Hoffman, 1963 (Diplopoda, Polydesmida, Paradoxosomatidae)

Twenty-two new species of the genus Eviulisoma Silvestri, 1910, from the Eastern Arc Mountains, Tanzania, are described: E. acaciae sp. nov., E. aequilobatum sp. nov., E. akkariae sp. nov., E. angulatum sp. nov., E. articulatum sp. nov., E. biquintum sp. nov., E. breviscutum sp. nov., E. cetafi sp. nov., E. chitense sp. nov., E. commelina sp. nov., E. coxale sp. nov., E. ejti sp. nov., E. grumslingslak sp. nov., E. kalimbasiense sp. nov., E. navuncus sp. nov., E. nessiteras sp. nov., E. ottokrausi sp. nov., E. paradisiacum sp. nov., E. sternale sp. nov. and E. zebra sp. nov. from the Udzungwa Mts, E. culter sp. nov. from the Rubeho Mts and E. kangense sp. nov. from the Kanga Mts. Eviulisoma kwabuniense Kraus, 1958, and E. dabagaense Kraus, 1958, both from the Udzungwa Mts, are redesribed based on new material. Notes are provided on E. iuloideum (Verhoeff, 1941) based on type material. Eoseviulisoma Brolemann, 1920, is synonymized under Eviulisoma, based on newly collected material of E. julinum (Attems, 1909), type species of Eoseviulisoma. New material of Suohelisoma ulugurense Hoffman, 1964, type species of Suohelisoma Hoffman, 1964, has revealed that the gonopod structure is more similar to that of Eviulisoma than originally thought, but Suohelisoma is retained as a valid genus. Four species groups are recognized among Eviulisoma species from the Udzungwa Mts, but the need for a revision of the entire genus is emphasized. Two types of epizootic fungi are recorded from Eviulisoma spp., and an enigmatic amorphous mass, which may be a kind of plugging substance, is recorded from the gonopod tips and excavated sixth sternum of several species.

A revision of dragon millipedes I: genus Desmoxytes Chamberlin, 1923, with the description of eight new species (Diplopoda, Polydesmida, Paradoxosomatidae).

The dragon millipede genus Desmoxytes s.l. is split into five genera, based on morphological characters and preliminary molecular phylogenetic analyses. The present article includes a review of Desmoxytes s.s., while future articles will deal with Hylomus Cook and Loomis, 1924 and three new genera which preliminarily are referred to as the ‘acantherpestes’, ‘gigas’, and ‘spiny’ groups. Diagnostic morphological characters of each group are discussed. Hylomus is resurrected as a valid genus and the following 33 species are assigned to it: H. asper (Attems, 1937), comb. n., H. cattienensis (Nguyen, Golovatch & Anichkin, 2005), comb. n., H. cervarius (Attems, 1953), comb. n., H. cornutus (Zhang & Li, 1982), comb. n., H. draco Cook & Loomis, 1924, stat. rev., H. enghoffi (Nguyen, Golovatch & Anichkin, 2005), comb. n., H. eupterygotus (Golovatch, Li, Liu & Geoffroy, 2012), comb. n., H. getuhensis (Liu, Golovatch & Tian, 2014), comb. n., H. grandis (Golovatch, VandenSpiegel & Semenyuk, 2016), comb. n., H. hostilis (Golovatch & Enghoff, 1994), comb. n., H. jeekeli (Golovatch & Enghoff, 1994), comb. n., H. lingulatus (Liu, Golovatch & Tian, 2014), comb. n., H. laticollis (Liu, Golovatch & Tian, 2016), comb. n., H. longispinus (Loksa, 1960), comb. n., H. lui (Golovatch, Li, Liu & Geoffroy, 2012), comb. n., H. minutuberculus (Zhang, 1986), comb. n., H. nodulosus (Liu, Golovatch & Tian, 2014), comb. n., H. parvulus (Liu, Golovatch & Tian, 2014), comb. n., H. phasmoides (Liu, Golovatch & Tian, 2016), comb. n., H. pilosus (Attems, 1937), comb. n., H. proximus (Nguyen, Golovatch & Anichkin, 2005), comb. n., H. rhinoceros (Likhitrakarn, Golovatch & Panha, 2015), comb. n., H. rhinoparvus (Likhitrakarn, Golovatch & Panha, 2015), comb. n., H. scolopendroides (Golovatch, Geoffroy & Mauriès, 2010), comb. n., H. scutigeroides (Golovatch, Geoffroy & Mauriès, 2010), comb. n., H. similis (Liu, Golovatch & Tian, 2016), comb. n., H. simplex (Golovatch, VandenSpiegel & Semenyuk, 2016), comb. n., H. simplipodus (Liu, Golovatch & Tian, 2016), comb. n., H. specialis (Nguyen, Golovatch & Anichkin, 2005), comb. n., H. spectabilis (Attems, 1937), comb. n., H. spinitergus (Liu, Golovatch & Tian, 2016), comb. n., H. spinissimus (Golovatch, Li, Liu & Geoffroy, 2012), comb. n. and H. variabilis (Liu, Golovatch & Tian, 2016), comb. n. Desmoxytes s.s. includes the following species: D. breviverpa Srisonchai, Enghoff & Panha, 2016; D. cervina (Pocock,1895); D. delfae (Jeekel, 1964); D. des Srisonchai, Enghoff & Panha, 2016; D. pinnasquali Srisonchai, Enghoff & Panha, 2016; D. planata (Pocock, 1895); D. purpurosea Enghoff, Sutcharit & Panha, 2007; D. takensis Srisonchai, Enghoff & Panha, 2016; D. taurina (Pocock, 1895); D. terae (Jeekel, 1964), all of which are re-described based mainly on type material. Two new synonyms are proposed: Desmoxytes pterygota Golovatch & Enghoff, 1994, syn. n. (= Desmoxytes cervina (Pocock, 1895)), Desmoxytes rubra Golovatch & Enghoff, 1994, syn. n. (= Desmoxytes delfae (Jeekel, 1964)). Six new species are described from Thailand: D. aurata Srisonchai, Enghoff & Panha, sp. n., D. corythosaurus Srisonchai, Enghoff & Panha, sp. n., D. euros Srisonchai, Enghoff & Panha, sp. n., D. flabella Srisonchai, Enghoff & Panha, sp. n., D. golovatchi Srisonchai, Enghoff & Panha, sp. n., D. octoconigera Srisonchai, Enghoff & Panha, sp. n., as well as one from Malaysia: D. perakensis Srisonchai, Enghoff & Panha, sp. n., and one from Myanmar: D. waepyanensis Srisonchai, Enghoff & Panha, sp. n. The species can mostly be easily distinguished by gonopod structure in combination with other external characters; some cases of particularly similar congeners are discussed. All species of Desmoxytes s.s. seem to be endemic to continental Southeast Asia (except the ‘tramp’ species D. planata). Some biological observations (relationship with mites, moulting) are recorded for the first time. Complete illustrations of external morphological characters, an identification key, and distribution maps of all species are provided.

Dalmatosomatidae, a new monotypic family, and Dalmatosoma agaricum gen. et sp. nov. (Diplopoda: Chordeumatida: Craspedosomatidea) from Croatia, Balkan Peninsula.

A new millipede species, Dalmatosoma agaricum gen. et sp. nov., is described from a cave in Dalmatia (Croatia). The new taxon is clearly unique among chordeumatidans in both anterior and posterior gonopod structure and shows some noteworthy habitus features. We therefore here establish a new monotypic family, viz., Dalmatosomatidae, for the given taxon and place it within the suborder Craspedosomatidea. The new family is briefly discussed and compared with all other chordeumatidans.

On two new species of potamid and sesarmid crabs (Decapoda, Brachyura) from caves in Myanmar

Two new species of brachyuran crabs are represented in a recent collection from caves in southern Myanmar [= Burma]. Demanietta burmanica sp. nov. (Potamidae) is the third species of Demanietta Bott, 1966, recorded from the country, and is closest to D. renongensis (Rathbun, 1904) from Thailand, but differs in the form of the carapace and details of the male first gonopod structure. Pseudosesarma brehieri sp. nov. (Sesarmidae) is allied to P. edwardsii (De Man, 1887) and P. crassimanum (De Man, 1887), both from the Mergui Archipelago, but can be easily distinguished by the distinctive form of its male first gonopod.

A new species of the millipede genus Cryptocorypha Attems, 1907, from Myanmar (Diplopoda: Polydesmida: Pyrgodesmidae)

A new species of the rather large, basically tropical/subtropical Asian genus Cryptocorypha is described from western Myanmar: C. perplexa sp.n. This is the 13th congener, also being the first to be reported from Myanmar. It differs from all sufficiently well described species of the genus in having 20 body segments in the M, combined with apparently the most complex gonopod structure.

A Review of the GenusObelostreptusAttems, 1909 (Diplopoda, Spirostreptida, Spirostreptidae) with the Description of a New Species from Kenya

ABSTRACT The east African millipede genus Obelostreptus Attems, 1909 is revised to include four species, new distribution records are given, and a new combination is established. In addition, the genus is removed from the family Harpagophoridae and placed in the Spirostreptidae. A new species, O. bilamellatus VandenSpiegel sp. n. from Kenya is described, and Mardonius nakitawa (Silvestri 1907) is removed from the genus Mardonius Attems, 1914 to become the fourth known species, O. nakitawa comb. n., in Obelostreptus. An identification key to the species of Obelostreptus based on male gonopod structure is also presented.

A new cavernicolous species of crab of the genusBalssiathelphusaBott, 1969 (Crustacea, Brachyura, Gecarcinucidae) from eastern Borneo

ABSTRACT A fourth species of gecarcinucid freshwater crab of the genus Balssiathelphusa Bott, 1969, is described from a cave system in eastern Kalimantan, Indonesia in Borneo. It is closest to B. cursor Ng, 1986, from Kalimantan, but can easily be distinguished from congeners by its relatively wider carapace, elongated ambulatory legs and characteristic male first gonopod structure. Although found only in caves, it is not regarded as a troglobite because its eyes are not reduced and the cornea are fully pigmented.

Review of the millipede family Trichopolydesmidae in the Oriental realm (Diplopoda, Polydesmida), with descriptions of new genera and species.

In the Oriental Region, the large, basically Northern Hemisphere family Trichopolydesmidae is shown to currently comprise 18 genera and 43 species. Based mainly on gonopod structure, all of them, as well as the whole family, are (re)diagnosed, including five new genera and seven new species. These new taxa are keyed, also being the first to be described from Indochina in general and from Vietnam in particular: Aporodesmella gen. n., with three species: A. securiformis sp. n. (the type species), A. similis sp. n. and A. tergalis sp. n., as well as the following four monotypic genera: Deharvengius gen. n., with D. bedosae sp. n., Gonatodesmus gen. n., with G. communicans sp. n., Helicodesmus gen. n., with H. anichkini sp. n., and Monstrodesmus gen. n., with M. flagellifer sp. n. In addition, Cocacolaria hauseri Hoffman, 1987, hitherto known only from New Ireland Island, Papua New Guinea, is redescribed based on material from Vanuatu whence it is recorded for the first time. One of the new genera, Gonatodesmus gen. n., provides a kind of transition or evolutionary bridge between Trichopolydesmidae and Opisotretidae, thus reinforcing the assignment of these two families to the single superfamily Trichopolydesmoidea.