Vertebral Formula Research Articles

Distribution, morphology, and natural history observations of the Colombian weasel, Neogale felipei

ABSTRACT The Colombian weasel, Neogale felipei, is a rare carnivoran known only from nine localities, eight in Colombia and one in Ecuador. Recent records have expanded our understanding of the distribution and threats that this mammal faces, but the species is still among the rarest Neotropical carnivores. Here, we present an update to the distribution of N. felipei based on a recent record obtained in the Cordillera Occidental (Western Cordillera) of Colombia, and information on internal and external morphology using noninvasive technique such as X-rays of museum preserved specimens. We also documented the presence of lice, Neotrichodectes minutus, which is the first documented ectoparasite of the species. With the new records, the species is currently known from 12 localities (11 in Colombia and one in Ecuador). We also present the first radiographic analyses for N. felipei and the obtained vertebral formula (49 total vertebrae) fits into the range reported for the species and other mustelids. Considering that the Colombian weasel is one of the rarest carnivores of the Neotropics, our work represents a noteworthy contribution to several aspects of the anatomy, distribution, and natural history of this rare carnivoran.

Macro‐anatomical investigations on the skeleton of the Egyptian hedgehog (Hemiechinus auratus aegyptius)

AbstractThe skeletal anatomy of wild animals plays a major role in their adaptation to their habitats. Information regarding the skeletal architecture of the Egyptian long‐eared hedgehog (Hemiechinus auratus aegyptius), a terrestrial and nocturnal insectivorous mammal, was lacking. Current work described the detailed bone formation of this species' skeleton grossly and morphometrically. Skeletons of five adults, apparently healthy hedgehogs of both sexes, aged 10 ± 2 months, were obtained. Preparation of the bones was accomplished by using a hot water maceration procedure. The skull was elongated. The external sagittal crest and temporal lines were unclear. The mental foramen was ventral to P2. The angular process of the mandible was large. The vertebral formula was C7, T13, L6, S3, Ca 13–15. The transverse foramen was absent in the seventh cervical vertebra. The sternum was formed of five sternal segments. There was a supratrochlear foramen on the distal part of the humerus diaphysis, connecting the radial and the olecranon fossae. The radius and ulna were fused by connective tissue. The carpals had three bones in the proximal row and four bones in the distal row. There were five metacarpals with five digits. The acetabulum was circular and had deep acetabular fossa. The foramen obturatum was ovoid. The pelvic symphysis was confined only to the ischium. The greater trochanter of the femur was lower than the level of the femoral head. The trochanteric fossa was deep and oval. Tibia and fibula fused distally. Two tarsals were in the proximal row and four in the distal row. There were five metatarsals with five digits. These findings provide the anatomical basis for understanding the adaptation mechanisms of this hedgehog species to their feeding habits and habitats and aim to help veterinarians, taxonomists, and wildlife biologists' in future biomedical and comparative skeletal anatomical studies.

Vertebral formula and numerical variations in the spine of the Antarctic and southern South American penguins (Aves: Sphenisciformes)

Abstract The vertebral column in tetrapods consists of several constant regions, namely the cervical, thoracic, lumbar, sacral, and caudal regions. Each of these regions is characterized by a specific number of vertebrae, contributing to the overall vertebral formula. Supernumerary and/or missing vertebrae have only been sporadically mentioned for penguins, and the specific vertebral formula is only determined for some non-passeres orders. Variations in the anatomy and vertebral number of South American and Antarctic penguin species are evaluated here. Sixty-six specimens of Aptenodytes forsteri, Pygoscelis adeliae, P. antarcticus, P. papua, Spheniscus magellanicus, and Eudyptes chrysocome were examined to establish the vertebral formula for six South American and Antarctic species, reporting the type and frequency of the variations found in the generalized configuration. We found no intraspecific variation in respect of the number of cervical as well as cervicothoracic vertebrae in all penguin species studied. Intra- and interspecific variation occur in the thoracic, synsacral, and caudal regions comprising 6–7, 13–14 and 5–8 vertebrae, respectively. Particularly, the variations were found in the transitional zones between one region and another and/or between synsacral segments.

A new snake eel species of the genus Ophichthus (Anguilliformes: Ophichthidae) from the southeast coast of India, Bay of Bengal, with the taxonomic account of Ophichthus chilkensis.

A new species of the ophichthid eel of the family Ophichthidae is described based on five specimens collected from the Mudasalodai fish landing center, off Cuddalore coast, southeast coast of India, Bay of Bengal. Ophichthus naevius sp. nov. is distinguished from its congeners by having a unique color pattern: dorsal body with numerous dense dark spots or patches, ventral body pale yellowish green, dorsal-fin origin just before pectoral-fin tip, vertebral formula: 12-14/52-53/134-138, and teeth on jaw uniserial and pointed. The study also reports the range extension and molecular evidence of Ophichthus chilkensis from South India. Molecular analyses were performed for both species, and their phylogenetic relationship suggests that the new species exhibits 10.2% genetic divergence with its congener Ophichthus sangjuensis, followed by Ophichthus brevicaudatus (10.4%), and Ophichthus sp. 1 (11.8%) also forms the closest clade in both Bayesian inference and maximum likelihood (ML) tree. Similarly, according to the topology of the ML tree, the species O. chilkensis forms a clade with Ophichthus sp. 5, Ophichthus remiger, Ophichthus frontalis, Ophichthus sp. 6, and Ophichthus rex, suggesting that it would be the genetically closest congener.

Regionalization of the vertebral column and its correlation with heart position in snakes: Implications for evolutionary pathways and morphological diversification.

Spinal regionalization has important implications for the evolution of vertebrate body plans. We determined the variation in the number and morphology of vertebrae across the vertebral column (i.e., vertebral formula) for 63 snake species representing 13 families using intracolumnar variation in vertebral shape. Vertebral counts were used to determine the position of the heart, pylorus, and left kidney for each species. Across all species we observed a conspicuous midthoracic transition in vertebral shape, indicating four developmental domains of the precloacal vertebral column (cervical, anterior thoracic, posterior thoracic, and lumbar). Using phylogenetic analyses, the boundary between the anterior and posterior thoracic vertebrae was correlated with heart position. No associations were found between shifts in morphology of the vertebral column and either the pylorus or left kidney. We observed that among taxa, the number of preapex and postapex vertebrae could change independently from one another and from changes in the total number of precloacal vertebrae. Ancestral state reconstruction of the preapex and postapex vertebrae illustrated several evolutionary pathways by which diversity in the vertebral column and heart position have been attained. In addition, no conspicuous pattern was observed among the heart, pylorus, or kidney indicating that their relative positions to each other evolve independently. We conclude that snakes exhibit four morphologically distinct regions of the vertebral column. We discuss the implications of the forebody and hindbody vertebral formula on the morphological diversification of snakes.

Does the phenotypic morphology of the human brachial plexus reflect the theoretical development of concomitant regulation in thoracolumbar spines and nerves?

Experimental evidence identified that thoracolumbar mutants caused by Hox genes 7-10 mutants also involve a craniocaudal shift and/or the addition or reduction of segments of the limb plexus roots. This study investigated whether the theoretical concomitant shift of the brachial plexus roots in human different thoracolumbar counts is shared as confirmed in those of the human lumbosacral plexus. The phenotypic morphology of the brachial plexus and its arterial interaction on 20 sides of 10 atypical human thoracolumbar counts out of the 354 sides of the 177 cadavers, were compared with those of 52 sides of 26 cases in a typical human vertebral formula (7C_12T_5L_5S). Regardless of the course and branching patterns of the axillary artery, our results showed that the main brachial plexus roots were composed of only five segments of the 5th-9th spinal nerves, with small contributions from the 4th and/or 10th nerves. This root composition is identical to a typical human thoracolumbar formula, and therefore, neither a craniocaudal shift nor additional/reduced main roots occurred in our thoracolumbar variants. Unlike the concomitant shift of the lumbosacral plexus roots, our present cases suggest that the phenotypic morphology of the human brachial plexus may be less likely to show theoretical craniocaudal shifts, further data on the root changes in different vertebral formulae are needed for its accurate validation.

Gymnothorax poikilospilus, a new moray eel (Teleostei: Anguilliformes: Muraenidae) from Penghu Islands, western Taiwan

Gymnothorax poikilospilus sp. nov. is described based on two specimens collected from Penghu Islands, western Taiwan. It is a medium-sized brown moray that body covered with several rows of inconspicuous large dark brown patches on the back of body and dorsal fin. It has slightly elongated and arched jaws similar to the common characteristic of the genus Enchelycore Kaup, but the dentition supports it belongs to typical morays of the genus Gymnothorax Bloch. The new species can be distinguished from other similar Indo-Pacific brown morays by the combination of dentition, vertebral formula, and morphometric measurements. Molecular analyses based on 612 bp of mitochondrial COI gene also support it as a distinct species.

Two new species of the snake eel genus Bascanichthys (Anguilliformes: Ophichthidae) from the northwestern Pacific.

Two new species of the elongate snake eel genus Bascanichthys are described from the northwestern Pacific. Bascanichthys kabeyawan sp. nov. is described based on a single specimen collected from estuary of southern Taiwan. It is characterized by having head 4.6% TL; tail 52.3% TL; body depth at gill opening 1.1% TL; predorsal-fin length 58.4% HL; snout length 10.9% HL; body bicolored, head without bands; lateral-line pores anterior to anus 104; vertebral formula 4-103-224. Bascanichthys ryukyuensis sp. nov. is described based on two specimens collected from the shallow water of Okinawa-jima Island, Ryukyu Islands of southern Japan. It is characterized by having head 3.7-4.3% TL; tail 43.3-44.2% TL; predorsal-fin length 40.7-45.4% HL; snout length 11.3-13.1% HL; body pale brown, head without distinct dark bands after preservation; lateral-line pores anterior to anus 114-118; total vertebrae 207-216, mean vertebral formula 2-116-212; and dorsal-fin origin before middle of head.

Anatomy of the vertebral column, ribs and sternum in orange rumped agouti (Dasyprocta leporina Linnaeus, 1758): Structural and Functional perspectives.

The axial skeleton of orange rumped agouti, Dasyprocta leporina, was studied for better understanding of its locomotor behaviour. The bones from eight adult agoutis of both sexes were observed for their anatomical features and functional significance. The vertebral formula was found to be C7 T12 L7 S5 Cy5-6 . The well-developed occipital crest, caudally oriented prominent axis spine and well-developed transverse processes from C3 -C7 indicated a highly flexible neck with greater sagittal mobility. Articular facets were horizontal in anterior series while oblique in the posterior series, which enabled them to perform both lateral and sagittal movements during locomotion. The caudally directed thoracic spines, T12 as anticlinal vertebra and prominent mamillary process in the posterior series were suggestive of strong dorso-ventral flexion/extension and rotation. The robust lumbar vertebrae, well-developed transverse processes with cranio-ventral extension, were the feature for powerful sagittal/dorsoventral movement. The presence of spinous processes and well-developed transverse processes in all caudal vertebrae was an indication of a highly movable tail. The ribs were 13 pairs with first seven as sternal and six as asternal. They were laterally compressed in the anterior series as a cursorial adaptation. A strong muscular attachment to vertebrae provides this rodent speed, agility, dexterity and strength suitable for survival in food chain.

Homeotic change in segment identity derives the human vertebral formula from a chimpanzee‐like one

One of the most contentious issues in paleoanthropology is the nature of the last common ancestor of humans and our closest living relatives, chimpanzees and bonobos (panins). The numerical composition of the vertebral column has featured prominently, with multiple models predicting distinct patterns of evolution and contexts from which bipedalism evolved. Here, we study total numbers of vertebrae from a large sample of hominoids to quantify variation in and patterns of regional and total numbers of vertebrae in hominoids. We compile and study a large sample (N=893) of hominoid vertebral formulae (numbers of cervical, thoracic, lumbar, sacral, caudal segments in each specimen) and analyze full vertebral formulae, total numbers of vertebrae, and super-regional numbers of vertebrae: presacral (cervical, thoracic, lumbar) vertebrae and sacrococcygeal vertebrae. We quantify within- and between-taxon variation using heterogeneity and similarity measures derived from population genetics. We find that humans are most similar to African apes in total and super-regional numbers of vertebrae. Additionally, our analyses demonstrate that selection for bipedalism reduced variation in numbers of vertebrae relative to other hominoids. The only proposed ancestral vertebral configuration for the last common ancestor of hominins and panins that is consistent with our results is the modal formula demonstrated by chimpanzees and bonobos (7 cervical-13 thoracic-4 lumbar-6 sacral-3 coccygeal). Hox gene expression boundaries suggest that a rostral shift in Hox10/Hox11-mediated complexes could produce the human modal formula from the proposal ancestral and panin modal formula.

A new radiological measurement method used to evaluate the modified transconjunctival orbital fat decompression surgery

PurposeA new radiological method was used to evaluate the plastic effect of modified transconjunctival orbital fat decompression surgery in patients with inactive thyroid-associated ophthalmopathy.MethodsIn this study, 10 inactive patients (14 eyes) with moderate to severe thyroid-associated ophthalmopathy were selected. The patients underwent modified transconjunctival orbital fat decompression surgery. According to the results of a spiral CT scan before and 6 months after the surgery, the INFINITT system workstation was used to measure the eyeball protrusion value. According to the results obtained by the PHLIPS IntelliSpace Portal elliptical area and line segment measurement tools, the standard elliptical vertebral volume formula was used to calculate the muscular cone inner volume. Changes in eyeball protrusion and the inner volume of the muscular cone before and after surgery were examined. Statistical analysis of the correlation between the two parameters was performed.ResultsRadiological measurement results confirmed that removing the orbital fat in the muscle cone during surgery was effective for alleviating eyeball protrusion in patients with thyroid-associated ophthalmopathy (P < 0.05). This surgery caused an obvious change in the muscle cone inner volume (P < 0.05). And there was significant correlation between changes in eyeball protrusion and muscle cone inner volume (r = 0.797, P = 0.0006, P < 0.05).ConclusionThe radiological assessment method used in this study is simple and easy to implement. For inactive patients with moderate to severe thyroid-associated ophthalmopathy who just want to improve their appearance, the modified orbital fat decompression surgery is worth considering.

A new arrowtooth eel of genus emMeadia/em (Synaphobranchidae: Ilyophinae) from Vietnam, South China Sea.

Meadia minor sp. nov., a scaless ilyophine eel, is described on the basis of 10 specimens collected from off Quy Nhon, central coast of Vietnam. It can be distinguished from its congeners in having a relatively long trunk (21.3-25.0% TL) which is longer than head length; a short and blunt snout (21.4-23.7% HL); gill opening close to pectoral-fin base; interbranchial space broad (20.7-26.2% HL); dorsal-fin origin above posterior third of pectoral fin; body depth 24-28 times in TL; total vertebrae 118-122; mean vertebral formula 7-33-121; and a small body size, reaching 330 mm TL. The generic status of the new species is discussed. Short descriptions of two congeners are provided.

First data on the structure of the vertebral column in Gobio and Romanogobio species (Actinopterygii, Cypriniformes, Gobionidae) from Ohrid Lake and the Vardar River basin

The validity of four gudgeon species known for the ichthyofauna of North Macedonia has been a matter of different taxonomic disputes (except forGobio ohridanusKaraman, 1924). Recently, a restoration of the species status was proposed forGobio balcanicusDimovski et Grupče, 1977 andRomanogobio banarescui(Dimovski et Grupče, 1974). So far,Romanogobio stankoi(Karaman, 1974), has not been a part of any recent investigation and it is still considered as a junior synonym ofRomanogobio elimeius(Kattoulas, Stephanidis et Economidis, 1973) orR. banarescuidue to the lack of distinctive morphological characters. The osteological characters in the structure of the vertebral column, have significance to the systematics of the gudgeons, especially in elevation ofRomanogobioat the level of genus. To contribute to resolving the taxonomic status in these gudgeon species, the goal of this paper is to identify distinctive characters by presenting and analyzing the structure of their vertebral column. Samples were inspected from the fish collections in the Institute of Biology (G. ohridanus), the Institute of Animal Science (G. balcanicus), and the Macedonian Museum of Natural History (bothRomanogobiospecies). Fish samples were X-rayed as well as cleared and double-stained. Obtained data on the number of vertebrae were presented through the vertebral formula following Naseka (1996). Multiple Correspondence Analysis (MCA) was used to check the interrelation between taxa and the number of vertebrae in all units of the vertebral column.G. balcanicusis distinguished fromG. ohridanusmainly in the predorsal and preanal subregion (10 vs. 11 vertebrae and 1 vs. 0 vertebrae, respectively), whileR. stankoidistinguishes fromR. banarescuiby the number of vertebrae in the preanal and postanal subregion (2 vs. 4 vertebrae and 19 vs. 17 vertebrae, respectively). The structure of vertebral column offers distinctive morphological characters for the four gudgeon species from Ohird Lake and the Vardar River basin.

Radiographic evaluation of congenital vertebral anomalies in Korean raccoon dogs (Nyctereutes procyonoides koreensis).

BackgroundThe normal vertebral anatomy of Korean raccoon dogs and their variants require research attention as a prerequisite for identifying pathologies and anomalies.ObjectivesThis retrospective study aimed at describing the vertebral formula and congenital vertebral anomalies in Korean raccoon dogs (Nyctereutes procyonoides koreensis).MethodsRadiographs of 82 raccoon dogs (42 males, 40 females) acquired from May 2013 to June 2020 in the Gangwon Wildlife Medical Rescue Center were reviewed to evaluate the cervical, thoracic, and lumbar vertebrae of the spine.ResultsNormal morphology of all vertebrae was observed in 50 of the 82 raccoon dogs, and the vertebral formula was cervical 7, thoracic 13, and lumbar 7. Congenital vertebral anomalies were found in 32 raccoon dogs: transitional vertebrae (TV) in 31 and block vertebrae in 2. Two raccoon dogs had 2 types of vertebral anomalies: one had TV and block vertebra, and the other had 2 types of TV. Twenty-nine raccoon dogs had thoracolumbar TV (TTV) and 3 had lumbosacral TV. TTV was morphologically classified into 4 different types: unilateral extra-rib in 5 raccoon dogs, bilateral extra-ribs in 14, bilateral elongated transverse processes in 4, and an asymmetric mixed formation of extra-rib with elongated transverse process in 6.ConclusionsThis study showed that TTV is common in Korean raccoon dogs, and that the vertebral formula is relatively diverse. The bilateral extra-ribs type TTV is the most common variant, which is almost similar to normal rib to be confused the radiographic evaluation.

Two New Moray Eels of Genera Diaphenchelys and Gymnothorax (Anguilliformes: Muraenidae) from Taiwan and the Philippines.

Two new moray eels of the genera Diaphenchelys and Gymnothorax from Taiwan and the Philippines are described. Diaphenchelys laimospila sp. nov. is described based on two specimens that represent the third species and a new geographic record of the genus. It can be distinguished from the other two congeners by the number of cephalic sensory pores, vertebral formula, morphometric measurements, and the coloration pattern. Gymnothorax pseudokidako sp. nov. is a muraenid with a dark brown body covered by pale snowflake-like blotches. It differs from the most similar species Gymnothorax kidako (Temminck and Schlegel) by having a relatively short tail (50.5-53.0% vs. 52.9-56.4% of TL), more dentary teeth (17-26 vs. 16-20), fewer total vertebrae (134-139 vs. 137-143), and the absence of white margin on anal fin (vs. prominent white margin). These two new species were also confirmed by molecular analyses, the mitochondrial COI gene (593 bp) for D. laimospila, and the nuclear EGR3 gene (767 bp) for G. pseudokidako.

A new white-spotted moray eel, Gymnothorax aurocephalus sp. nov. (Muraenidae: Muraeninae) from Andaman Sea, India.

Gymnothorax aurocephalus sp. nov. is described herein based on 4 specimens. Three were collected from off Swaraj Dweep Island of Andaman and Nicobar Islands (AN Islands) from a depth of 125-130 m and one specimen off Interview Island, AN Islands at a depth of 90 m. This new species is distinguishable from its congeners by the following combination of characters: chocolate brown color overlain with small irregular white spots, golden skin shadings close to rictus; anus slightly before midbody; pointed and serrated jaw teeth; uniserial teeth in jaws and vomer; vertebral formula 7/61/148-149. The species is compared to all its congeners with white spots.

Vertebral pattern variation in the North Sea harbor porpoise (Phocoena phocoena) by computed tomography.

Vertebral series in the harbor porpoise (Phocoena phocoena) include cervical, thoracic, lumbar, and caudal. In contrast to studying skeletons from museums, in which small bones can be missed, evaluation of full body computed tomography (CT) scans provides an overview of the vertebral column, while maintaining interrelationship of all structures. The aim of this study was to document variations in vertebral patterning of the harbor porpoise via evaluation of CT images of intact stranded harbor porpoises. The harbor porpoises were divided into age classes, based on developmental stage of reproductive organs on postmortem examination and closure of proximal humeral physis on CT. Numbers of vertebrae per series, fusion state of the syncervical, type of first hemal arch, number of double articulating ribs, and floating ribs were recorded based on CT images. Included in the study were 48 harbor porpoises (27 males and 21 females), which were divided in two age classes (27 immatures and 21 adults). Total vertebral count varied from 63 to 68 with vertebral formula range C7T12‐14L12‐16Cd29‐33. Twenty‐five different vertebral formulas were found, of which C7T13L14Ca30 was the most common (n = 8, 17%). Thoracic vertebrae with six, seven, or eight double articulating ribs and zero, one, or two vertebrae with floating ribs were seen. Four different fusion states of the syncervical and four types of hemal arches were recognized. This study showed a great variation in vertebral patterning in the harbor porpoise, with homeotic and meristic variation in the thoracic, lumbar, and caudal vertebral series.

A review of the genus Strophidon (Anguilliformes: Muraenidae), with description of a new species.

Strophidon McClelland is a muraenid genus with characteristic appearance of a very elongated body, a large mouth cleft and anteriorly placed eyes. The nomenclature and taxonomic history of species within Strophidon are contentious and its members are easily misidentified. In the present study, species of the genus Strophidon are revised based on morphological and molecular data, and five species are considered valid, including S. dawydoffi Prokofiev, S. dorsalis (Seale), S. sathete (Hamilton), S. ui Tanaka and a new species, S. tetraporus. Strophidon tetraporus sp. nov. is described based on 15 specimens from Indonesia, the Philippines, Taiwan and Vietnam with the unique characteristic of the constant presence of the fourth infraorbital pore among species of Strophidon. The intraspecific variation of vertebral formula within S. dorsalis is discussed based on molecular data. Muraena macrurus Bleeker and Thyrsoidea longissima Kaup are synonyms of S. sathete that can be distinguished from the most similar congener S. ui by a longer tail, smaller eyes and more inner maxillary and inner dentary teeth. A key to identify species of Strophidon is provided. The distribution and maximum size of each species are also re-evaluated.

Osteology and radiology of the vertebral column in the white-eared opossum (Didelphis albiventris).

The white-eared opossum present a higher roadkill number in Brazil, and the vertebral column is often affected when some type of trauma occurs. Thus, this study describes the osteology and radiology of the vertebral column in white-eared opossum to serve as a basis for support in the veterinary clinical care, since the casuistry of care of this marsupial has increased every year. Radiographs of the cervical (C), thoracic (T), lumbar (L), sacral (S) and caudal (Cd) segments of the vertebral column were taken in thirty-five white-eared opossums (Didelphis albiventris). Furthermore, ten opossums without evident vertebral acquired or congenital abnormalities at the radiographic study were selected for anatomical study. Osteology was correlated with the radiographic images. The use of radiographs allowed the identification of congenital and acquired vertebral changes, as well as the identification of anatomical structures, their distribution and morphology and the number of vertebrae. The vertebral formula varied in the white-eared opossum. In 27 of 35 white-eared opossums (77.2%) with normal vertebral morphology, three vertebral formulas were observed: C7/T13/L6/S2 (62.9%), C7/T13/L5/S2 (5.7%) and C7/T13/L7/S2 (8.6%). Most of the specimens presented 27 caudal vertebrae. The anticlinal vertebra was identified as T10 in 77.2% and T11 in 22.8% of opossums. Cervical block vertebra was observed in two animals and sacrocaudal block vertebra in one animal. The haemal arches could be seen from Cd3-Cd4 in 80% and Cd2-Cd3 in 20% of opossums. The white-eared opossum showed a slender vertebral column with a relatively short thoracic region, a relatively long lumbar region and a highly flexible lumbosacral transition, suggesting that this animal is a fast-running and agile opossum. Therefore, these findings may serve as a basis for further research and support the veterinary clinical care, since the casuistry of care for this marsupial has increased every year.

Three new species of the barracudina genus Lestidium (Aulopiformes: Paralepididae) from the Indo-West Pacific.

Three new species of the genus Lestidium with complete lateral line are described from the Indo-west Pacific Ocean. Lestidium longilucifer sp. nov., from Western Australia and Taiwan, belongs to the Lestidium atlanticum species complex and can be separated from other congeners by having 41-43 prehaemal vertebrae, 85-88 total vertebrae and 126-146 total lateral-line scales; and body proportions. Lestidium australis sp. nov. from eastern Australia and Lestidium rofeni sp. nov. from Taiwan and the Philippines together with Lestidium prolixum form the L. prolixum species complex. These three species can be separated from each other by a combination of different fin positions, vertebral formula, number of lateral-line scales and pigmentation.