Anomalohalacarus biformis Abe 1996
Creators: name: Shin, Jong Hak
name: Chang, Cheon Young
name: lee, Jimin
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Halacaridae
Anomalohalacarus
Anomalohalacarus biformis

description: Anomalohalacarus biformis Abé, 1996
Anomalohalacarus biformis Abé 1996 a: 8, figs. 1–4.
Materials
Type status: Other material. Occurrence: individualCount: 1; sex: female; lifeStage: adult; preparations: mounted in glycerine on H-S slide; occurrenceID: 11FB49B6-4A93-5B4A-AC25-CBF05899B385; Taxon: scientificName: Anomalohalacarus biformis; kingdom: Animalia; phylum: Arthropoda; class: Arachnida; order: Trombidiformes; family: Halacaridae; genus: Anomalohalacarus; specificEpithet: biformis; scientificNameAuthorship: Abé, 1996; Location: higherGeography: Northwest Pacific Ocean; continent: East Asia; country: Korea (the Republic of); countryCode: KR; stateProvince: Jeju-do; municipality: Seogwipo-city; locality: Jungmun-saekdal Beach, Saekdal-dong; verbatimDepth: 0.5–1 m; verbatimCoordinates: 33 ° 14 ' 42 " N 126 ° 24 ' 39 " E; Identification: identifiedBy: Shin, Chang & Lee; dateIdentified: 2024; Event: samplingProtocol: suction; eventDate: 22 / 06 / 2022; Record Level: institutionID: MABIK CR 00257798; institutionCode: Marine Biodiversity Institute of Korea; basisOfRecord: PreservedSpecimen
Type status: Other material. Occurrence: individualCount: 1; sex: female; lifeStage: adult; preparations: mounted in glycerine on H-S slide; occurrenceID: AF088E60-3754-5280-B937-8D2A8154A5FA; Taxon: scientificName: Anomalohalacarus biformis; kingdom: Animalia; phylum: Arthropoda; class: Arachnida; order: Trombidiformes; family: Halacaridae; genus: Anomalohalacarus; specificEpithet: biformis; scientificNameAuthorship: Abé, 1996; Location: higherGeography: Northwest Pacific Ocean; continent: East Asia; country: Korea (the Republic of); countryCode: KR; stateProvince: Jeju-do; municipality: Seogwipo-city; locality: Jungmun-saekdal Beach, Saekdal-dong; verbatimDepth: 0.5–1 m; verbatimCoordinates: 33 ° 14 ' 42 " N 126 ° 24 ' 39 " E; Identification: identifiedBy: Shin, Chang & Lee; dateIdentified: 2024; Event: samplingProtocol: suction; eventDate: 22 / 06 / 2022; Record Level: institutionID: MABIK CR 00257799; institutionCode: Marine Biodiversity Institute of Korea; basisOfRecord: PreservedSpecimen
Type status: Other material. Occurrence: individualCount: 1; sex: male; lifeStage: adult; preparations: mounted in glycerine on H-S slide; occurrenceID: 0D79C7CD-B876-5B77-A698-15C33C0F830C; Taxon: scientificName: Anomalohalacarus biformis; kingdom: Animalia; phylum: Arthropoda; class: Arachnida; order: Trombidiformes; family: Halacaridae; genus: Anomalohalacarus; specificEpithet: biformis; scientificNameAuthorship: Abé, 1996; Location: higherGeography: Northwest Pacific Ocean; continent: East Asia; country: Korea (the Republic of); countryCode: KR; stateProvince: Jeju-do; municipality: Seogwipo-city; locality: Jungmun-saekdal Beach, Saekdal-dong; verbatimDepth: 0.5–1 m; verbatimCoordinates: 33 ° 14 ' 42 " N 126 ° 24 ' 39 " E; Identification: identifiedBy: Shin, Chang & Lee; dateIdentified: 2024; Event: samplingProtocol: suction; eventDate: 22 / 06 / 2022; Record Level: institutionID: MABIK CR 00257800; institutionCode: Marine Biodiversity Institute of Korea; basisOfRecord: PreservedSpecimen
Type status: Other material. Occurrence: individualCount: 1; sex: male; lifeStage: adult; preparations: mounted in glycerine on H-S slide; occurrenceID: 2693CF12-5FB3-52F1-8AF8-582B7C2FCAAE; Taxon: scientificName: Anomalohalacarus biformis; kingdom: Animalia; phylum: Arthropoda; class: Arachnida; order: Trombidiformes; family: Halacaridae; genus: Anomalohalacarus; specificEpithet: biformis; scientificNameAuthorship: Abé, 1996; Location: higherGeography: Northwest Pacific Ocean; continent: East Asia; country: Korea (the Republic of); countryCode: KR; stateProvince: Jeju-do; municipality: Seogwipo-city; locality: Jungmun-saekdal Beach, Saekdal-dong; verbatimDepth: 0.5–1 m; verbatimCoordinates: 33 ° 14 ' 42 " N 126 ° 24 ' 39 " E; Identification: identifiedBy: Shin, Chang & Lee; dateIdentified: 2024; Event: samplingProtocol: suction; eventDate: 22 / 06 / 2022; Record Level: institutionID: MABIK CR 00257801; institutionCode: Marine Biodiversity Institute of Korea; basisOfRecord: PreservedSpecimen
Description
Female
Idiosoma (Fig. 5 A) elongate, 298 µm long (284–298 µm, mean = 291 µm, n = 2), 103 µm wide (98–103 µm, mean = 101 µm, n = 2), length-to-width ratio about 2.89 (2.89–2.90, mean = 2.90, n = 2). AD and PD clearly separated by membranous cuticle with transversely parallel wavy striae. OC absent. Membranous cuticle between AD and PD occupying 59 % of idiosoma; decorated with three pairs of ds (ds- 2 to ds- 4) and 1 pair of glp- 2 situated at anterior 42 % of idiosoma dorsolaterally.
AD (Fig. 5 A and C) 67 µm long (58–67 µm, mean = 63 µm, n = 2), about 0.22 times as long as idiosoma, 36 µm wide (32–36 µm, mean = 40 µm, n = 2), length-to-width ratio 1.86; rectangular in shape with truncated anterior margin and slightly convex posterior margin; ornamented with a longitudinally weakly split areolation in the middle to posterior third of AD, 1 pair of glp- 1 at anterior 21 % of AD laterally, followed by 1 pair of ds- 1.
PD (Fig. 5 A, D) undivided, 43 µm long (39–43 µm, mean = 41 µm, n = 2), about 0.14 times as long as idiosoma, 23 µm wide (21–23 µm, mean = 22 µm, n = 2), length-to-width ratio 1.87; smaller than AD, 0.64 times as long as AD, 0.64 times as wide as AD; convex anterior and lateral margins, and slightly blunt posterior margin; with 2 pairs of glp (glp- 3 and glp- 4) placed at anterior 12 % and 87 % of PD, respectively and 1 pair of ds- 6 at posterior glp- 4.
Five pairs of dorsal setae (Fig. 5 A): ds- 1 positioned at anterior 40 % of AD laterally; 3 pairs of ds (ds- 2 to ds- 4) more and less evenly spaced on membranous cuticle at 20 %, 38 %, and 63 % of idiosoma, respectively; ds- 3 shorter than ds- 2 and ds- 4; ds- 5 absent; ds- 6 shortest, situated at posterior edge of PD.
All ventral plates (Fig. 5 B) small and separated by membranous cuticle with striae, excluding between left and right plates of AE. AE (Fig. 5 B) 69 µm long (58–69 µm, mean = 64 µm, n = 2), about 0.23 times as long as idiosoma, 32 µm wide (26–32 µm, mean = 29 µm, n = 2), length-to-width ratio 2.16; divided into left and right plates by smooth membranous cuticle (Fig. 5 E), of which membranous cuticle with striae extending posterior ventral setae about 1 / 6 posterior part; distance between plates widest, 24 μm near insertion of leg I and narrowing gradually towards posterior part; each plate bearing 2 ventral, 1 lateral setae, and 1 epimeral pore; posterior ventral seta (41 µm long) shorter than others; epimeral pore inserted at border of epimera I and II, about anterior 66 % of AE.
PE (Fig. 5 B) 48 µm long (45–48 µm, mean = 47 µm, n = 2), about 0.16 times as long as idiosoma, 21 µm wide (20–21 µm, mean = 21 µm, n = 2), length-to-width ratio 2.29; situated at anterior 63–81 % of idiosoma; each plate bearing 1 dorsolateral, 2 ventral setae and 1 vestigial scar of seta; ventral setae located at anterolateral corner and at half of PE, respectively.
GP (Fig. 6 A) divided into 3 plates, consisting of 1 pair of anterior and 1 posterior genital plates; anterior genital plates sub-rectangular-shaped, located on either side of genital foramen, 18 µm long (12–18 µm, mean = 15 µm, n = 2), 11 µm wide (8–11 µm, mean = 10 µm, n = 2), length-to-width ratio of 1.64; posterior genital plate inverted triangular posterior to genital foramen, 7 µm long (n = 2), 22 µm wide (20–22 µm, mean = 21 µm, n = 2), length-to-width ratio of 0.32; 3 pairs of pgs, consisting of foremost one located on membranous cuticle anterior to genital foramen and the other 2 pairs on anterior genital plates. Genital foramen (Fig. 6 A) 17 µm long (15–17 µm, mean = 16 µm, n = 2), 3 µm wide (n = 2); slender, pointed at both anterior and posterior tips, widest at anterior 15 % of genital foramen; sgs absent; genital groove placed between posterior genital plate and anal foramen. Ovipositor (Fig. 5 B) tube-shaped, anterior end not reaching anterior edge of PE.
Gnathosoma (Fig. 5 A and B) 118 µm long (114–118 µm, mean = 116 µm, n = 2), about 0.36 times as long as idiosoma, 31 µm wide (29–31 µm, mean = 30 µm, n = 2), length-to-width ratio of 3.81; without ornamentation on surface. Rostrum (Fig. 5 B) 59 µm long, slightly longer than gnathosomal base, its anterior tip not extending beyond distal end of P- 2; 4 pairs of rostral setae, composing of 2 pairs of short proto- and deutorostral setae situated on distal end of rostrum and 2 pairs of long trito- and basirostral setae at anterior 29 % and 59 % of rostrum ventrally, respectively. Palp (Fig. 5 F) 4 - segmented, 11, 58, 9, and 15 µm long, respectively; P- 1 without setae and spines; P- 2 longest, with 1 short proximal and 1 plumose distal setae, dorsally; P- 3 shortest, with 1 dorsomedial spine; P- 4 conical, its terminal end bifurcated, with 3 proximal and 1 tiny distal setae. Chelicera (Fig. 5 A and G) 119 µm long, consisting of basal and movable distal segments; basal segment 107 µm long, with wide proximal part and slender distal part (38 %); movable segment 20 µm long, with about 25 fine denticles dorsally. Tectum (Fig. 5 A) tiny, weakly convex at middle of anterior edge.
All legs (Fig. 6 B – E) slender, leg I longest, 257 µm long, and legs II – IV 174 µm, 175 µm, and 186 µm long (0.67, 0.68, and 0.72 times as long as leg I), respectively. Chaetotaxy for legs I – IV as in Anomalohalacarus angustus sp. nov., except for tibiae 10-6 - 5 - 6 (5); arrangement of legs I – IV similar to the new species. All legs with a pair of lateral claws bearing 1 accessory process dorsally and with single median claw; lateral claws of tarsus I shortest.
Male
Idiosoma (Fig. 5 H), 294 µm long (294–311 µm, mean = 303 µm, n = 2), 102 µm wide (102–110 µm, mean = 106 µm, n = 2), length-to-width ratio about 2.83–2.88; almost similar to female, except for length ratio of AD / PD and genital region. AD (Fig. 5 H and I) 62 µm long (62–76 µm, mean = 69 µm, n = 2), about 0.21 times as long as idiosoma, 35 µm wide (35–42 µm, mean = 39 µm, n = 2), length-to-width ratio 1.77. PD (Fig. 5 H and J) 52 µm long (52–63 µm, mean = 58 µm, n = 2), about 0.18 times as long as idiosoma, 26 µm wide (26–32 µm, mean = 29 µm, n = 2), length-to-width ratio 2.00; undivided, rectangular with truncated anterior and posterior margins; smaller than AD, 0.84 times as long as AD and 0.74 times as wide as AD.
GA (Fig. 6 H) 50 µm long (50–57 µm, mean = 54 µm, n = 2), about 0.17 times as long as idiosoma, 38 µm wide (38–43 µm, mean = 41 µm, n = 2), length-to-width ratio 1.32; elliptical, with a depressed posterior region behind GO and gradually tapering towards posterior ends at both sides; with 7 pairs of filiform pgs, foremost pgs at level of anterior sgs. GO (Fig. 6 H) 20 µm long, (20–26 µm, mean = 23 µm, n = 2), about 0.40 times as long as GA, 12 µm wide (12–17 µm, mean = 15 µm, n = 2); with 2 pairs of sgs, each situated at anterior 26 % and 58 % of genital sclerites, respectively. Spermatocyte (Fig. 6 H) extending beyond anterior end of PE.
Distribution
Japan (Abé 1996 a), Korea (this study).
Co-occurrence
Anomalohalacarus biformis occurred at a beach on the southern coast of Jeju Island, South Korea. Specimens were obtained by filtering sand with medium-sized grains, along with Actacarus pacificus, Acarochelopodia sp., Acaromantis sp., Copidognathus sp., Maracarus sp., Rhombognathus sp., Simognathus sp., and Scaptognathus sp. In addition to halacarids, harpacticoid copepods, nematodes, polychaetes, and ostracods were also present in the sand sediments.
description: Published as part of Shin, Jong Hak, Chang, Cheon Young & lee, Jimin, 2024, Two psammobiont species of Anomalohalacarus (Acari, Halacaridae) from South Korea, pp. e 135719 in Biodiversity Data Journal 12 on page e135719, DOI: 10.3897/BDJ.12.e135719