taxonID	type	description	language	source
FA5C8792FFAEFFF07285F2AFFB554DBA.taxon	type_taxon	Type species. Tenuipalpus erythreus Ewing, 1917: 52.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAEFFF07285F2AFFB554DBA.taxon	diagnosis	Diagnosis. As per genus, with setae f 2 present. Subgenus Pentamerismus includes 12 species.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAEFFF07285F130FC184C5F.taxon	type_taxon	Type species: Tenuipalpus erythreus Ewing, 1917: 152.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAEFFF07285F130FC184C5F.taxon	diagnosis	Diagnosis. After Beard et al. (2014): palpi five-segmented; anterior margin of prodorsum with anterior notch forming a pair of lobes anterior to setae v 2, or margin smoothly rounded; dorsal opisthosoma with 12 or 13 pairs of setae (i. e. f 2 present or absent); three pairs of pseudanal setae (ps 1 – 3).	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAFFFF17285F4F9FBBA4B98.taxon	type_taxon	Type species. Tenuipalpus taxi Haller, 1877: 85.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAFFFF17285F4F9FBBA4B98.taxon	diagnosis	Diagnosis. As per genus, with setae f 2 absent. Subgenus Oligomerismus includes 11 species.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAFFFF17285F4F9FBBA4B98.taxon	discussion	Remark: The species P. (O.) collinus is an exception, because it has two pairs of pseudanal setae in contrast to all other species of the genus having three pairs of setae. See the comments below.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAFFFF17285F594FEC14E64.taxon	discussion	The species Pentamerismus collinus Meyer & Van Dis, 1993 formally belongs to the subgenus Oligomerimus, since setae f 2 are absent. However, we exclude this species from the diagnostic key, because its placement in the genus Pentamerismus seems to be questionable. In contrast to all other species of the genus, it has only two pairs of pseudanal setae (ps), and setae f 2 occupy sublateral position. Meyer & Van Dis (1993) highlighted that P. collinus shares the presence of two pairs of pseudanal setae with the genus Phytoptipalpus; however, as these authors attached greater taxonomic significance to the number of dorsosublateral setae, they considered setae f 2 to be in a lateral position and referred this species to Pentamerismus. It is crucial to understand which morphological character are persistent enough to be used for clear generic diagnoses of tenuipalpids. Both of the aforementioned characters (position of dorsal opisthosomal setae and number of pseudanal setae) have been used in combination to differentiate various tenuipalpid genera. The taxonomic significance of the number of pseudanal setae could not be denied at the generic level in the family Tenuipalpidae, in particular, in the genera Tenuipalpus, Extenuipalpus, Ultratenuipalpus, etc. (Mesa et al. 2009; Beard et al. 2016). We suggest that the presence of two pairs of ps setae should be confirmed by a careful re-examination of the type specimens of P. collinus, and if this were the case, then it would be reasonable to place this species in the genus Phytoptipalpus.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAFFFF87285F0C8FEAF48C1.taxon	materials_examined	Material examined. Six females (KSMAAS 14 - Ten-Pen- 01 – 06) and three males (KSMAAS 14 - Ten-Pen- 07 – 09), ex Zygophyllum simplex Linnaeus (Zygophyllaceae), Saudi Arabia, Riyadh province, King Saud University, near College of Food and Agriculture Science, 24 ° 50 ’ 57 ’’ N, 46 ° 33 ’ 149 ’’ E, 30 April 2014, coll. M. Kamran.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAFFFF87285F0C8FEAF48C1.taxon	description	Complementary description of female (n = 6) Dorsum (Figure 1). Idiosoma oval in shape, length of body (excluding gnathosoma) 225 (212 – 237); (including gnathosoma) 275 (263 – 287) long; 127 (119 – 113) wide. Anterior margin of dorsal propodosoma rounded with no anterior notch; dorsal propodosomal setae (v 2, sc 1, sc 2) subspatulate serrate; length of seta v 2 half as long as distance between setae v 2 – v 2; dorsal propodosoma with weak longitudinal striation medially; posterior opisthosoma entirely with longitudinal striations; transverse striation in line of setae d 1; medial striation between the setae c 1 and d 1 dome shape pattern, slightly irregular dorsolaterally; opisthosoma with three pairs of dorsocentral setae (c 1, d 1, e 1), two pairs of dorsolateral setae (c 2, d 2), seven pairs of dorsolateral setae (c 3, d 3, e 2, e 3, f 3, h 1, h 2); first row of dorsal opisthosomal setae c 1, c 2, c 3 subspatulate; other central and lateral dorsal opisthosomal setae broadly spatulate, becoming broader toward posterior; setae f 2 absent. Lengths of dorsal setae as follows: v 2 14 – 17, sc 1 18 – 22, sc 2 19 – 24, c 1 18 – 22, c 2 15 – 19, c 3 14 – 17, d 1 16 – 22, d 2 15 – 19, d 3 14 – 17, e 1 13 – 18, e 2 13 – 16, e 3 14 – 19, f 3 10 – 14, h 2 10 – 14, h 1 10 – 15. Distances between dorsal setae: v 2 – v 2 33 – 39, v 2 – sc 1 25 – 30, sc 1 – sc 2 23 – 28, sc 1 – sc 1 63 – 72, sc 2 – sc 2 91 – 99, c 1 – c 1 41 – 47, c 1 – c 2 25 – 30, c 2 – c 3 11 – 15, c 2 – c 2 89 – 97, c 3 – c 3 118 – 129, c 1 – d 1 31 – 37, c 2 – d 2 33 – 43, c 3 – d 3 42 – 50, d 1 – d 1 35 – 40, d 1 – d 2 20 – 24, d 2 – d 3 13 – 15, d 2 – d 2 100 – 112, d 3 – d 3 105 – 114, d 1 – e 1 40 – 47, d 3 – e 3 18 – 22, e 1 – e 1 20 – 25, e 1 – e 2 35 – 42, e 2 – e 3 20 – 23, e 2 – e 2 105 – 113, e 3 – e 3 90 – 99, e 3 – f 3 20 – 25, f 3 – f 3 67 – 74, f 3 – h 2 19 – 24, h 1 – h 1 15 – 19, h 1 – h 2 15 – 20, h 2 – h 2 45 – 51, e 1 – h 1 42 – 49. Venter (Figure 2). Ventral propodosoma with transverse striation; longitudinal striations between setae 3 a and 4 a, transverse striations posterior to 4 a and anterior to setae ag, immediately posterior to coxae IV with transverse striae laterally; oblique to transverse striae anterolateral to genital shield. Length of setae: 1 a 90 – 112, 1 b 19 – 26, 1 c 15 – 20, 2 b 16 – 20, 2 c 20 – 26, 3 a 15 – 22, 3 b 13 – 17, 4 a 15 – 20, 4 b 14 – 19, ag 17 – 22, g 1 14 – 19, g 2 16 – 20, ps 3 7 – 10, ps 2 9 – 13, ps 1 11 – 14. Ventral setae 1 a whip-like, three to four times longer than 3 a. Genital and anal shields coarsely striated (Figure 2 A); aggenital setae (ag) serrated, equal in length to genital setae (g 1 – 2) also serrated; anal shields with three pairs of setae (ps 1 – 3), ps 1 – 2 narrowly lanceolate. Distances between ventral setae: 1 a – 1 a 20 – 27, 3 a – 3 a 36 – 40, 4 a – 4 a 26 – 33, 1 b – 1 c 11 – 15, 2 b – 2 c 20 – 22, 1 a – 3 a 51 – 59, 3 a – 4 a 30 – 38, 4 a – ag 56 – 63, ag – ag 13 – 15, g 1 – g 1 15 – 20, g 2 – g 2 35 – 41, g 1 – g 2 10 – 13, ag – g 1 22 – 27, ag – g 2 21 – 28, g 1 – ps 1 32 – 38, g 1 – ps 2 30 – 37, g 1 – ps 3 8 – 32, g 2 – ps 1 37 – 44, g 2 – ps 2 30 – 34, g 2 – ps 3 27 – 32. Spermatheca globular elongate (Figure 2 B). Gnathosoma (Figure 3). Subcapitulum with one pair of setae m (Figure 3 A) Rostrum reaching to the distal end of genu I; palp five segmented, palp tarsus with one solenidion and two eupathidia distally, where inner eupathidion is distinctly smaller; palp tibia with two setae, palp femur and genu without setae (Figure 3 B). Legs (Figure 4). Legs are short, less than one third the length of idiosoma; Length of leg I 78 – 85; leg II 66 – 71; leg III 70 – 75; leg IV 71 – 78. Setal formulae of leg segments as follows: coxae 2 - 2 - 1 - 1; trochanters 1 - 1 - 2 - 1; femora 4 - 4 - 2 - 1; genua 2 - 2 - 0 - 0; tibiae 4 - 4 - 3 - 3; tarsi 8 (1 ω) - 8 (1 ω) - 5 - 5. Dorsal setae on femur I – III, genu I-II and tibiae I narrowly lanceolate and distinctly serrated (Figure 4). Tarsus I and II each with one antiaxial solenidion (ω) 10 – 12 and 8 – 10 long, respectively (Figure 4). Tarsal claws uncinate and empodia pad-like. Description of male (n = 3) Dorsum (Figure 5). Idiosoma oval in shape, length of body (excluding gnathosoma) 144 – 149; (including gnathosoma) 197 – 200 long; width 83 – 88 wide. Anterior margin of dorsal propodosoma rounded with no anterior notch; dorsal propodosomal setae (v 2, sc 1, sc 2) subspatulate serrate; length of seta v 2 more than half the distance between setae v 2 – v 2; dorsal propodosoma with circular longitudinal striae becoming weak medially as in female; dorsal opisthosomal setae c 1 – 3 subspatulate; other dorsal opisthosomal setae broadly spatulate, becoming broader toward posterior; setae f 2 absent. Lengths of dorsal setae as follows: v 2 16 – 18, sc 1 15 – 18, sc 2 16 – 17, c 1 11 – 15, c 2 10 – 13, c 3 8 – 10, d 1 10 – 11, d 2 8 – 11, d 3 9 – 13, e 1 8 – 13, e 2 10 – 13, e 3 8 – 10, f 3 10 – 11, h 2 10 – 12, h 1 9 – 11. Distances between dorsal setae: v 2 – v 2 23 – 25, v 2 – sc 1 16 – 18, sc 1 – sc 2 16 – 18, sc 1 – sc 1 46 – 49, sc 2 – sc 2 52 – 55, c 1 – c 1 26 – 29, c 1 – c 2 16 – 21, c 2 – c 3 8 – 9, c 2 – c 2 53 – 54, c 3 – c 3 71 – 75, c 1 – d 1 18 – 22, c 2 – d 2 21 – 23, c 3 – d 3 27 – 32, d 1 – d 1 24 – 25, d 1 – d 2 11 – 12, d 2 – d 3 8 – 10, d 2 – d 2 47 – 49, d 3 – d 3 65 – 66, d 1 – e 1 16 – 19, d 3 – e 3 34 – 35, e 1 – e 1 16 – 21, e 1 – e 2 15 – 16, e 2 – e 3 15 – 16, e 2 – e 2 48 – 50, e 3 – e 3 44 – 49, e 3 – f 3 8 – 10, f 3 – f 3 32 – 36, f 3 – h 2 11 – 12, h 1 – h 1 5 – 7, h 1 – h 2 7 – 8, h 2 – h 2 23 – 25, e 1 – h 1 29 – 31. Venter (Figure 6). Ventral propodosoma and inter-coxal area between setae 1 a and 3 a with transverse striation; area between coxae III – IV with longitudinal striae, area posterior setae 4 a with transverse striae. Length of setae: 1 a 42 – 49, 1 b 28 – 29, 1 c 22 – 25, 2 b 19 – 20, 2 c 18 – 21, 3 a 15 – 18, 3 b 13 – 17, 4 a 15 – 17, 4 b 13 – 15, ag 13 – 17, g 1 10 – 11, g 2 9 – 10, ps 3 10 – 11, ps 2 10 – 12, ps 1 9 – 11. Ventral setae 1 a whip-like, three times longer than 3 a; aggenital setae (ag); genital setae serrated (g 1 – 2); anal shields with 3 pairs of serrated setae (ps 1 – 3). Distances between ventral setae: 1 a – 1 a 13 – 16, 3 a – 3 a 23 – 28, 4 a – 4 a 16 – 18, 1 b – 1 c 8 – 10, 2 b – 2 c 15 – 17, 1 a – 3 a 43 – 46, 3 a – 4 a 20 – 22, 4 a – ag 54 – 56, ag – ag 11 – 13, g 1 – g 1 6 – 7, g 2 – g 2 14 – 16, g 1 – g 2 4 – 5, ag – g 1 24 – 26, ag – g 2 28 – 33 (Figure 6 A). Aedeagus (Figure 6 C) long, pointed at tip. Gnathosoma (Figure 6 B). Rostrum reaching to the distal end of genu I; palp (Figure 6 B) 5 segmented, palp tarsus with one solenidion and two eupathidia distally; palp tibia with two setae, palp femur and genu without setae. Legs (Figure 7). Legs are short, less than half length of idiosoma; Length of legs measured from (trochanter to tarsus), leg I 66 – 67; leg II 61 – 62; leg III 59 – 60; leg IV 64 – 66. Setal formulae of leg segments as follows: coxae 2 - 2 - 1 - 1; trochanters 1 - 1 - 2 - 1; femora 4 - 4 - 2 - 1; genua 2 - 2 - 0 - 0; tibiae 4 - 4 - 3 - 3; tarsi 8 (1 ω) - 8 (1 ω) - 5 - 5. Tarsus I and II each with one antiaxial solenidion (ω ”) 8 (7 - 8), 7 (6 – 7) long. Tarsal claws uncinate and empodia pad-like.	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
FA5C8792FFAFFFF87285F0C8FEAF48C1.taxon	discussion	Remarks. The Saudi specimen of Pentamerismus (Oligomerismus) retusus morphologically resembles the original (Meyer 1979; South Africa) and supplementary descriptions (Meyer 1993; Namibia). The Saudi specimens were compared with the images of the holotype of P. (O.) retusus. The dorsomedial striae on propodosoma are longitudinal and weak in Saudi specimens (female and male), while in compared specimens, striae form a circular pattern (Meyer 1979, holotype) or surface is rugose (Meyer 1993). The pattern of striation between setal rows C and D in our specimens is mostly transverse with a small region of arched striae compared to irregular to transverse striaein the holotype (Meyer 1979). The propodosomal setae of Saudi specimen (female and male) are subspatulate serrate in shape compared to broadly spatulate (Meyer 1979) and broadly lanceolate to subspatulate (Meyer 1993). The length of dorsal propodosomal setae v 2 is half the distance v 2 – v 2 compared to one third in the holotype (Meyer 1979, 1993).	en	Mirza, Jawwad Hassan, Elgoni, Nasreldeen Ahmed, Kamran, Muhammad, Alatawi, Fahad Jaber (2025): Subgenera of the genus Pentamerismus McGregor (Acari: Tenuipalpidae) with the re-description of Pentamerismus retusus Meyer and a key to species of the world. Zootaxa 5601 (1): 143-156, DOI: 10.11646/zootaxa.5601.1.7, URL: https://doi.org/10.11646/zootaxa.5601.1.7
