[Crustacea • 2024] Sipadantonius roihani • A New Genus and Species of Pseudocyclopidae Giesbrecht, 1893 (Copepoda: Calanoida) from the marine cave “Turtle Tomb” of Sipadan Island, Sabah, Malaysia

Sipadantonius roihani  

Boonyanusith, Wongkamhaeng & Azman, 2024

  

DOI: doi.org/10.3897/zookeys.1219.133132 

facebook.com/AzmanBAR

Abstract

A new genus and species of the family Pseudocyclopidae, Sipadantonius roihani gen. et sp. nov., was described based on specimens collected using a light trap in the marine cave of Sipadan Island, Sabah, Malaysia. The new genus is most related to Pinkertonius, primarily based on the similarity observed in the armament of ancestral segment IV of the male antennules, the armament of the female P5 Exp-3, the segmentation of the male P5, the armament of the maxillular basal exite, and the relative length of the ancestral segment XXVII of the antennules. Nevertheless, it distinguishes itself from Pinkertonius and all other genera of the family by the absence of the lateral seta of the basis of all swimming legs, the presence of an inner seta on the coxa of the female P5, the reduction of furcal setae I and III, as well as the specific armament of the ancestral segment XX of the antennules and the maxillular coxal endite. The female of Sipadantonius roihani gen. et sp. nov. has aesthetascs on the ancestral segments IV and XX of the antennules, as well as six setae on the maxillular coxal endite, exhibiting the most plesiomorphic characteristics of the family Pseudocyclopidae. The latter characteristic has not been recorded in the order Calanoida. It was hypothesised that the new species was a particle feeder living in the pelagic zone of the marine cave. The existence of the new species supported the assumption that the regional distribution of the family Pseudocyclopidae exhibited the Tethyan track, which might have been the subsequent result of the colonisation of the habitats prior to the closure of the Tethys Sea.

Key words: Crustacea, Southeast Asia, systematics, taxonomy, Zooplankton

Sipadantonius roihani gen. et sp. nov. female:
A habitus, dorsal view B habitus, lateral view C urosome, ventral view D urosome, lateral view E genital double-somite, ventral view F furcal rami, dorsal view G furcal rami, lateral view. Arrowheads indicate integumental pores.

Scale bars: 200 μm (A, B); 100 μm (C, D); 50 μm (E−G).

Sipadantonius roihani gen. et sp. nov. photographs of lateral surface of basis of swimming legs, female (A−E) and male (F):
A posterior hyaline process on basis of P1 (indicated by arrow) B P1 C P3 D P4 E, F P5. Arrowheads indicate cuticular windows on lateral margin of basis. Scale bars: 10 μm.

Order Calanoida Sars, 1903

Superfamily Pseudocyclopoidea Giesbrecht, 1893

Family Pseudocyclopidae Giesbrecht, 1893

Genus Sipadantonius gen. nov.

Etymology: Named after the type locality, Sipadan Island, Sabah, Malaysia, in combination with the -tonius stem from the existing generic name Pinkertonius Bradford-Grieve, Boxshall & Blanco-Bercial, 2014, alluding to the similarity of the genus Pinkertonius. The gender is masculine.

 Sipadantonius roihani sp. nov.

Etymology: The specific epithet was conferred in honour of Mr Roihan Han, a Malaysian deep dive record holder (at a depth of 164 m), who also led the Turtle Tomb exploration activity. Consequently, the name is a noun in the genitive singular.

Chaichat Boonyanusith, Koraon Wongkamhaeng and Abdul-Rahim Azman. 2024. Sipadantonius roihani gen. et sp. nov., A New Genus and Species of Pseudocyclopidae Giesbrecht, 1893 (Copepoda, Calanoida) from the marine cave “Turtle Tomb” of Sipadan Island, Sabah, Malaysia. ZooKeys. 1219: 303-329. DOI: doi.org/10.3897/zookeys.1219.133132

 facebook.com/AzmanBAR/posts/10160711935500986

[Crustacea • 2024] Avatar nishidai & Kokeshioides surugaensis • Two New Genera and Species of the Parasitic Copepod Family Chondracanthidae Milne Edwards, 1840 (Copepoda: Cyclopoida) from Deep-Sea Fishes Off Suruga Bay, Japan

 Avatar nishidai

Aneesh, Ohtsuka, Kondo & Helna, 2024

 DOI: 10.1007/s11686-024-00820-3

Abstract

Purpose: 

The present paper describes two new genera and species of the parasitic copepod family Chondracanthidae Milne Edwards, 1840 based on specimens collected from two species of deep-sea fishes at a depth of 212 m off Suruga Bay, Japan. Avatar nishidai gen. et sp. nov. is described from the host fish Chaunax abei Le Danois, 1978 (Chaunacidae). Kokeshioides surugaensis gen. et sp. nov. is described from the host fish Setarches longimanus (Alcock, 1894) (Setarchidae).

Methods: 

Fresh specimens of chondracanthids were collected from the buccal cavity of two species of deep-sea fishes (fish hosts were frozen), Chaunax abei Le Danois, 1978 (Lophiiformes: Chaunacidae) and Setarches longimanus (Alcock, 1894) (Perciformes: Setarchidae), caught at a depth of 212 m in Suruga Bay, Japan (34° 37′48.87″ N, 138° 43′2.958″ E). Both the species are described and illustrated based on ovigerous females.

Results: 

The genus Avatar gen. nov. can readily be distinguished from all other chondracanthid genera by the following combination of features: cephalothorax slightly wider than long with anterior pair of large and posterior pair of small lateral lobes, and two pairs of ventro-lateral processes; the very posteriormost part of the first pedigerous somite contributes to the neck; cylindrical trunk with two pairs of blunt proximal fusiform processes; antennule with small knob terminally; antenna bearing distal endopodal segment; labrum protruding ventrally; two pairs of biramous legs each with 2-segmented rami. Kokeshioides gen. nov. has the following combinations of features that distinguish it from other chondracanthid genera: body flattened, without lateral processes; cephalothorax much wider than long, with paired anterolateral and posterolateral lobes, folded ventrally; the very posteriormost part of the first pedigerous somite contributes to the neck; mandible elongate; legs unique, heavily sclerotized, represented by two pairs of acutely pointed processes.

Conclusion: 

With the addition of two new genera presently reported, the family Chondracanthidae currently includes 52 valid genera. Among the described genera Avatar gen. nov. seems to be very primitive, while Kokeshioides gen. nov. is highly advanced. The deduced evolutionary history of chondracanthid genera is also discussed.

Keywords: Avatar, Chondracanthids, Copepoda, Fish parasite, Kokeshioides 

Taxonomy

Order Cyclopoida Burmeister, 1834

Family Chondracanthidae Milne Edwards, 1840

Genus Avatar gen. nov.

Etymology: The generic name is derived from a world-famous epic science fiction film, James Cameron’s “Avatar”, in which the dragon-like aerial predator “Mountain Banshee” with two pairs of wings reminds us of the present new taxon with two pairs of lateral processes on the trunk. Gender feminine.

  Avatar nishidai gen. et sp. nov.

Etymology: The specific name of the new species, ‘nishidai’, is dedicated to Mr. Yusuke Nishida (Hiroshima University) who found this enigmatic chondracanthid in the Suruga Bay, Japan. It is a noun in the genitive case.

Genus Kokeshioides gen. nov.

Etymology: The generic name is derived from a Japanese traditional wooden toy called “Kokeshi” and the Latin suffix -oides meaning “like”. Gender masculine.

  Kokeshioides surugaensis gen. et sp. nov.

Etymology: The specific name is derived from the type locality, Suruga Bay, Japan. It is in the nominative singular, gender masculine.

Conclusions: 

New material collected from two different species of deep-sea fishes of Suruga Bay, Japan were found to be different from all other known chondracanthid genera, and based on the clear morphological features we described two new monotypic genera. Accordingly, we described Avatar nishidai gen. et sp. nov. from Chaunax abei Le Danois, 1978 (Chaunacidae) and Kokeshioides surugaensis gen. et sp. nov. from Setarches longimanus (Alcock, 1894) (Setarchidae). By the description of two new genera in the presently reported study, the family Chondracanthidae currently includes 52 valid genera. Among the described genera Avatar gen. nov. seems to be very primitive, while Kokeshioides gen. nov. is highly advanced. The deduced evolutionary history of chondracanthid genera is also discussed in the present paper.

Panakkool Thamban Aneesh, Susumu Ohtsuka, Yusuke Kondo & Ameri Kottarathil Helna. 2024. Two New Genera and Species of the Parasitic Copepod Family Chondracanthidae Milne Edwards, 1840 (Copepoda: Cyclopoida) from Deep-Sea Fishes Off Suruga Bay, Japan. Acta Parasitologica. DOI: 10.1007/s11686-024-00820-3

[Crustacea • 2021] Tigriopus namsaiensis & T. wannapaensis • Two New Species of Tigriopus Norman, 1869 (Copepoda: Harpacticidae) from Chonburi Province, Thailand

Tigriopus namsaiensis & T. wannapaensis 

Chullasorn, Kangtia, Song & Khim, 2021

 DOI: 10.11646/zootaxa.5051.1.6

  facebook.com/157493158257614

 Researchgate.net/publication/355276559

 

Abstract

Two new species of the family Harpacticidae Dana, 1846, Tigriopus namsaiensis sp. nov. and T. wannapaensis sp. nov. were found in algal washings at Namsai and Wannapa beaches in Chonburi Province, Thailand. There are currently 14 known species in the genus, two of which, T. thailandensis Chullasorn, Ivanenko, Dahms, Kangtia & Yang, 2012 and T. sirindhornae Chullasorn, Dahms & Klangsin, 2013 were also discovered in Thailand. The genus Tigriopus Norman, 1869 has a worldwide distribution with nine species recorded from the Pacific Ocean (seven in the North Pacific and two in the South Pacific), four species from the Atlantic and adjacent seas, two species from the South Indian Ocean, and one species from Antarctica.

                Sexual dimorphism is expressed in the antennule, antenna, P2, P5, P6, and segmentation of the urosome. Tigriopus namsaiensis sp. nov. and T. wannapaensis sp. nov. are closely related to T. thailandensis and T. sirindhornae in sharing the following characters: fewer sensilla on the prosome; antennary exopod with one seta on exp-2; P4 exp-3 with two inner setae; female P5 baseoendopod with five setae; male P2 enp-2 with a seta fused to the segment; and male P5 exopod with five setae.

                Tigriopus namsaiensis sp. nov. closely resembles T. thailandensis, but the new species is characterized by four setae on the maxillulary coxa (three setae in T. thailandensis), the outermost seta on the female P6 is plumose (instead of the middle one), the lateral seta on the apical segment of the antennary exopod is discrete at the base (instead of fused to the segment), and the outermost seta of the male P5 exopod is plumose (instead of spinulose).

                Tigriopus wannapaensis sp. nov. is very closely related to T. sirindhornae, but the new species differs from the latter by the following characteristics: 2-segmented mandibular exopod (3-segmented in T. sirindhornae); five setae on the maxillulary coxa (instead of three); all setae on female P6 are plumose (instead of two plumose and one pinnate); the lateral seta on the apical segment of the antennary exopod is fused to the segment (instead of discrete at the base); and the outermost seta on the male P5 exopod is plumose (instead of spinulose).

                A dichotomous identification key to the 16 valid species of Tigriopus is provided.

Key words: Harpacticoida, identification key, morphology, Namsai Beach, taxonomy, Ulva clathrata, Wannapa Beach, Crustacea

 

Supawadee Chullasorn, Pawana Kangtia, Sung Joon Song and Jong Seong Khim. 2021. Two new species of Tigriopus Norman, 1869 from Chonburi Province, Thailand (Crustacea: Copepoda: Harpacticidae). Zootaxa. 5051(1); 41-67. DOI: 10.11646/zootaxa.5051.1.6

  facebook.com/157493158257614/posts/931063750900547

  Researchgate.net/publication/355276559_Two_new_species_of_Tigriopus_from_Chonburi_Province_Thailand

ได้ค้นพบฮาร์แพคทิคอยด์โคพีพอด 2 ชนิดใหม่ของโลก ได้แก่ Tigriopus namsaiensis จากบริเวณชายหาดน้ำใส จังหวัดชลบุรี และ Tigriopus wannapaensis จากชายหาดวอนนภา จังหวัดชลบุรี สัตว์กลุ่มนี้มีความสำคัญต่อระบบนิเวศทางทะเล เป็นตัวชี้วัดคุณภาพของน้ำและเป็นอาหารของสัตว์น้ำวัยอ่อนที่มีคุณค่าทางเศรษฐกิจ

[Crustacea • 2022] Metacyclops sakaeratensis & M. brancelji • Two New Species of Metacyclops Kiefer, 1927 (Copepoda, Cyclopoida) from Thailand and An Up-to-date Key to the Species Recorded in Asia

Metacyclops sakaeratensis

Athibai, Wongkamhaeng & Boonyanusith, 2022

DOI:  10.5852/ejt.2021.787.1621 

facebook.com/KoraonWongkamhaeng 

ABSTRACT

Metacyclops sakaeratensis sp. nov. and M. brancelji sp. nov. are described as being present in the mountainous areas of Northeastern and Southern Thailand, respectively. Two new species resemble M. woni in both sexes, but they are easily distinguished from their Cambodian relative by having: 1) transverse suture on the dorsal surface of the genital double-somite, 2) serrated hyaline frill on the posterior margin of third pedigerous somite, 3) different length / width ratio of caudal ramus, and 4) a row of spinule on caudal surface of intercoxal sclerite of the third swimming legs. The significant differences between M. sakaeratensis sp. nov. and M. brancelji sp. nov. are present in both sexes, including the body size, integumental ornamentation of the body surface, length / width ratio of caudal ramus, armature of the fifth swimming leg, and the male sixth swimming leg. In addition, an up-to-date key to the female of all fifteen species of Metacyclops recorded in Asia is provided.

Keywords: cave-dwelling copepod, karst, Sakaerat Environmental Research Station, Satun Province, Southeast Asia

 

Geographical location and details of the sampling sites.
A. Map of Thailand and a location of Nakhon Ratchasima, Satun and Songkhla Provinces.
B–C. Location (indicated by a black circle with no. 1) and sampling point of headwater stream in Nakhon Ratchasima Province.
D. Locations of caves in Satun and Songkhla Provinces (indicated by black circles with nos 2, 3, 4). E–F. Sampling points in Phupha Phet Cave. G–H. Sampling points in Rakhang Thong Cave and Khao Nui Cave, respectively.

Phylum Arthropoda von Siebold, 1848

Subphylum Crustacea Brünnich, 1772

Class Maxillopoda Dahl, 1956

Subclass Copepoda Milne-Edwards, 1840

Superorder Podoplea Giesbrecht, 1882

Order Cyclopoida Burmeister, 1834

Family Cyclopidae Rafinesque, 1815

Subfamily Cyclopinae Kiefer, 1927

Genus Metacyclops Kiefer, 1927

Metacyclops sakaeratensis sp. nov.

Diagnosis: 

Female. Body size moderate (0.73–0.75 mm; n = 3), with shallow integumental pits. Posterior margin of second pedigerous somite undulated; those of third and fifth pedigerous somites with serrated hyaline frill. Genital double-somite dorsally with two sensilla and transverse suture, representing the remnant of ancestral articulation of the sixth thoracic somite and the first abdominal somite. Anal operculum developed, reaching insertion of caudal ramus; free margin smooth and straight. Caudal rami ca 2.1–2.3 × as long as wide, with few spinules at anterior third length on lateral surface and at base of seta II, combined with a row of strong spinules latero-ventrally at base of seta III. Seta VI slightly shorter than seta III. Setal and spine formulae of exp-2 of P1–P4 5.5.5.5 and 3.4.4.3, respectively. P4 exp-2 with single apical spine; spine slightly shorter than segment. Inner spine on free segment of P5 as long as segment; outer seta on P5 ca 4.5 × as long as inner spine.

Male. Body slenderer and smaller than female (0.62–0.67 mm; n = 3). Caudal rami ca 2.2–2.4 × as long as wide. P6 with two elements; outer (dorsal) seta about twice as long as inner (ventral) spine.

Etymology: The species name is a noun. The specific epithet was raised after the ʻSakaeratʼ Subdistrict, where the new species was encountered

 Metacyclops brancelji sp. nov.

Diagnosis: 

Female. Body size moderate (0.89–0.96 mm; n = 6), without integumental pits. Posterior margin of second pedigerous somite undulated, those of third and fifth pedigerous somite with serrated hyaline frill. Genital double-somite dorsally with two sensilla and transverse suture, representing the remnant of ancestral articulation of the sixth thoracic somite and the first abdominal somite. Anal operculum developed, reaching insertion of caudal ramus; free margin smooth and concave. Caudal rami ca 2.6–2.9 × as long as wide, ornamented with 3–4 spinules at anterior third length on lateral surface and few spinules at base of seta II, combined with a row of strong spinules latero-ventrally at base of seta III. Seta VI slightly shorter than seta III. Setal and spine formulae of exp-2 of P1–P4 5.5.5.5 and 3.4.4.3, respectively. P4 exp-2 with single apical spine; spine slightly shorter than segment. Inner spine of free segment of P5 longer than segment, ca 1.5 × as long as segment; outer seta on P5 ca 2.5 × as long as inner spine.

Male. Body length 0.71–0.76 mm (n = 3). Caudal rami ca 2.5–2.8 × as long as wide. P6 with two elements; inner (ventral) spine robust, slightly shorter than outer seta.

Etymology: The name is a masculine noun in genitive singular, raised after Professor Dr Anton Brancelj (National Institute of Biology, Ljubljana, Slovenia) in honor of his great contribution to the diversity of subterranean Copepoda in Thailand.

Sujeephon Athibai, Koraon Wongkamhaeng and Chaichat Boonyanusith. 2022. Two New Species of Metacyclops Kiefer, 1927 (Copepoda, Cyclopoida) from Thailand and An Up-to-date Key to the Species Recorded in Asia. European Journal of Taxonomy. 787(1); 146-181. DOI:  10.5852/ejt.2021.787.1621

 facebook.com/KoraonWongkamhaeng/posts/3073417142986343

facebook.com/1893991337322344/posts/4907945665926881

[Crustacea • 2017] Revision of Family Megacalanidae (Copepoda: Calanoida)

Elenacalanus princeps (Brady, 1883).

photo: David Shale, UK.

DOI: 10.11646/zootaxa.4229.1.1

Abstract

The Megacalanidae were revised based on new and archived material. Taxonomic confusion that has existed in the family is discussed and a method is suggested for stabilising names. A detailed examination of the morphology of this family, using the light microscope, has added further useful characters that distinguish genera and species. The added, hitherto undescribed species include character states incompatible with aspects of previous generic definitions (e.g. presence or absence of setae on the maxillule coxal endite). Nevertheless, the cladistic and molecular analyses confirmed that there are at least four monophyletic clades mostly with high bootstrap support. These clades represent already defined genera, one of which [Elenacalanus nom. nov. (nomen novum)] replaces the preoccupied name Heterocalanus Wolfenden, 1906. Four previously described species have been re-assigned to Elenacalanus in new combinations: E. princeps (Brady, 1883), E. eltaninae (Björnberg, 1968), E. sverdrupi (Johnson, 1958) and E. inflatus (Björnberg, 1968). Eleven new species are described: three Megacalanus, one Bradycalanus, six Bathycalanus, and one Elenacalanus nom. nov. Bradycalanus pseudotypicus enormis Björnberg, 1968 has been raised to species status based on genetic data although it can be only be distinguished morphologically from Br. typicus by its large size. All four genera are differentially diagnosed and keys are provided to the genera and species. We confirm that all male right antennules are geniculate in the Megacalanidae. Thirteen males are known. Of these males, eight are newly described (Megacalanus frosti n. sp., M. ericae n. sp., M. ohmani n. sp., Bathycalanus bradyi (Wolfenden, 1905a), Ba. dentatus n. sp., Ba. milleri n. sp., Ba. unicornis Björnberg, 1968, and Elenacalanus tageae n. sp.). We cannot be absolutely certain that the correct males have been assigned to the appropriate female so our decisions await testing with new data. The cladistic analysis provides the first morphology-based phylogeny. This scheme served as a working hypothesis which was tested and corroborated using the newly gathered molecular data. Vertical and horizontal distributions are summarised.

Keywords: Crustacea, Megacalanus, Bradycalanus, Bathycalanus, Elenacalanus nom. nov., key, morphology, genes, phylogeny, Atlantic, Indian, Pacific, bathypelagic, abyssopelagic, Megacalanus frosti n. sp., M. ericae n.sp., M. ohmani n. sp., Bradycalanus abyssicolus n. sp., Bathycalanus dentatus n. sp., Ba. milleri n. sp., Ba. tumidus n. sp., Ba. adornatus n. sp., Ba. pustulosus n. sp., Ba. bucklinae n. sp., Elenacalanus tageae n. sp.

Janet M. Bradford-Grieve, Leocadio Blanco-Bercial and Geoffrey A. Boxshall. 2017. Revision of Family Megacalanidae (Copepoda: Calanoida). 

Zootaxa. 4229(1); 1–183. DOI: 10.11646/zootaxa.4229.1.1