Agauopsis legionium Pepato & Tiago, 2005, sp. nov.
Creators: name: Pepato, Almir R.
name: Tiago, Cláudio G.
Publisher: name: Zenodo
Year: 2005
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Halacaridae
Agauopsis
Agauopsis legionium

description: Agauopsis legionium sp. nov.
(Fig. 2–4)
Holotype: Female (MZUSP 16631) from intertidal rock shore at Martim de Sá Beach (23 38´S 45 24´W), September 13th 2001, coll. BIOTA /FAPESP.
Paratypes: Female (MZUSP 16632) from intertidal rock shore at Martim de Sá Beach (23 38´S 45 24´W), September 19th 2001, coll. BIOTA /FAPESP; three females (author's collection) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA /FAPESP; female (MZUSP 16633) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA /FAPESP; female (author's collection) on Pterocladiella capillacea (S.G.Gmel.) Santel. and Hommers, 1997 from intertidal rock shore at Cigarras Beach (23 44´S 45 4´W), November 24th 2000, coll. E. Nascimento; female (author's collection) on Hypnea musciformes (Wulfen) Lamouroux, 1813 from intertidal rock shore at Cigarras Beach (23 44´S 45 24´W), November 25th 2000, coll. E. Nascimento; three females (author's collection) from intertidal rock shore at Preta Beach (23 49'S 45 25´W), October 12th 2001, coll. A. R. Pepato; female (author’s collection) from intertidal rock shore at Toque Toque Grande Beach (23 50´S 45 31´W), April 10th 2001, coll. BIOTA /FAPESP; male (MZUSP 16634) from intertidal rock shore at Martim de Sá Beach (23 38´S 45 24´W), September 0 1st 2001, coll. BIOTA /FAPESP; four males (author’s collection) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA /FAPESP; two deutonymphs (author’s collection) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA /FAPESP; male within a quiescent deutonymph (author’s collection) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA /FAPESP; female within a quiescent deutonymph (author’s collection) from intertidal rock shore at Massaguassú Island (23 25´S 44 49´W), March 16th 2001, coll. BIOTA / FAPESP; four deutonymphs (author’s collection) from intertidal rock shore at Martim de Sá Beach (23 38´S 45 24´W), September 19th 2001, coll. BIOTA /FAPESP; two deutonymph (author’s collection) from intertidal rock shore at Figueira Beach (23 49’S, 45 24’W), January 22nd 2004, coll. C. Santos, C. G. Tiago and A. R. Pepato; deutonymph (MZUSP 16636) from intertidal rock shore at Toque Toque Grande Beach (23 50´S 45 31´W), December 12th 2001, coll. BIOTA /FAPESP; deutonymph (author's collection) from intertidal rock shore at Preta Beach (23 49'S 45 25´W), October 12th 2001, coll. A. R. Pepato; deutonymph (author's collection) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), April 0 8th 2001, coll. BIOTA /FAPESP; deutonymph (author's collection) from intertidal rock shore at Martim de Sá Beach (23 38´S 45 4´W), March 13th 2001, coll. BIOTA /FAPESP; protonymph (author’s collection) from intertidal rock shore at Massaguassú Island (23 25´S 44 49´W), March 16th 2001, coll. BIOTA /FAPESP; two prototonymphs (author's collection) from intertidal rock shore at Martim de Sá Beach (23 38´S 45 24´W), September 20th 2001, coll. BIOTA /FAPESP; two protonymphs (author’s collection) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA /FAPESP; protonymph (author’s collection) from intertidal rock shore at Figueira Beach (23 49’S, 45 24’W), January 22nd 2004, coll. C. Santos, C. G. Tiago and A. R. Pepato; protonymph (author’s collection) from intertidal rock shore at Toque Toque Grande Beach (23 50´S 45 31´W), April 10th 2001, coll. BIOTA /FAPESP; protonymph (author’s collection) from intertidal rock shore at Cambiri Point (23 37´S 45 24´W), March 15th 2001, coll. BIOTA /FAPESP; two larvae (MZUSP 16637, 16638) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA / FAPESP; two larvae (author’s collection) from intertidal rock shore at Baleia Beach (23 46´S 45 40´W), December 12th 2001, coll. BIOTA /FAPESP; larva (author’s collection) from intertidal rock shore at Figueira Beach (23 49’S, 45 24’W), January 22nd 2004, coll. C. Santos, C. G. Tiago and A. R. Pepato.
Description: Measurements obtained from the examined specimens are shown in Table I.
TABLE I. Measurements, in m, obtained from examined individuals of Agauopsis legionium sp. nov.
Female Male Deutonymph Protonymph Larva
Length Width Length Width Length Width Length Width Length Width
Idiosoma 445–540 295–415 393–413 265–305 345–387 237–279 242–323 171–227 186–237 143–166
Gnathosoma 170–205 75–103 153–157 68–76 120–140 61–73 91–104 46–55 79–80 43–47
AD 150–182 120–165 141–145 119–133 123–137 99–109 96–101 66–80 67–71 47–55 PD 168–210 150–198 176–187 153–165 111–141 110–121 87–97 84–93 86–88 70–77 OC 85–110 55–65 80–95 56–70 72–80 45–55 49–66 34–41 44–52 33 AE 175–200 295–365 149–166 251–280 144–154 227–244 106–119 153–186 99–101 133–140 GA 115–133 150–175 103–129 139–155 68–73 78–89 41–47 49–66 ­­­ ­­­
GO 80–96 46–63 51–60 32–40 ­­­ ­­­ ­­­ ­­­ ­­­ ­­­ Female: Females have all plates separated by membranous cuticle. Dorsal plates covered in most of their surface by shallow and wide polygonal fovea pierced by canaliculi along their edges; this ornamentation can be better seen under 400 times magnification (Fig. 1 B). Anterior dorsal plate bears an "H" shaped costae and PD has a divergent costae both made up of canaliculi arranged in panel on a slightly elevated stripe. Pair of ds­1 on AD at 0.28–0.39 of its overall length. Second to fourth pairs of dorsal setae on membranous cuticle. Pair of ds­5 on PD at 0.40–0.43 of its overall length.
Ventral plates pierced by canaliculi throughout. AE with three pairs of setae and a pair of slit­like epimeral pores. PE with three ventral and one dorsal seta. Posterior margin of AE and anterior margin of GA truncate. Distance between anterior edge of GA and GO measures 39–48 m, equaling 0.41–0.54 times length of GO. Genitoanal plate with three pairs of perigenital setae. Large eugenital setae with finger like projections could be seen through genital sclerite.
Gnathosoma 1.87–2.26 times longer than wide. Rostrum equaling 0.56–0.63 of overall length of gnathosoma. Tectum scaliform does not reach the end of P1. P2 3.7–4.0 times longer than high with a posterior dorsal seta. P3 with a medial pectinate spine. P4 with two basal setae and two apical spurs. Chelicerae reach the anterior extremity of rostrum.
Chaetotaxy of legs, with spines of leg I in Roman numerals: leg I, 1,2,9(IV),5(II),9(III),6(I); leg II, 1,2,6,5,7,3; leg III, 1,2,3,3,5,3; leg IV, 0,1,3,3,5,3. Tibia II bears three bipectinate setae. Tibiae III–IV with only two such setae. Spines on leg I with apical denticles and lateral rows of tiny pecten. Tarsus I with a pair of doublet eupathidia and a minute solenidium and a famulus on the posterior lateral edge. Tarsus II with medially spine­like and laterally slender parambulacral setae. Tarsi III–IV with only a blunt spine­like seta as parambulacral setae. Telofemora length/height ratio from telofemora II to IV: 1.87–1.95; 1.89–2.05; 1.94–2.06.
Lateral claws of tarsus I smooth, medial one bidentate. Lateral claws of tarsi II–IV with accessory tooth and pecten which is constituted of two rows of tines, one ventral and other medial with less than half amount of tines. Median claws of tarsi II–IV reduced to a median sclerite.
Male: Males are similar to females in most features. Anterior margin of GA truncate, separated from GO by a distance of 45–49 m which means 0.75–0.96 times GO´s length. Perigenital setae arranged in two rings around GO, 34–41 as a whole, inner rings with 11­ 14 setae, outer one with 23–28 setae. A pair of outlying setae lies at almost same level of the most anterior perigenital setae. Genital sclerites with five pairs of blunt subgenital setae. Spermatophorotype reaches anterior margin of GA and sometimes surpass it.
Juveniles: The juveniles show a conspicuous anterior projection on PD and dorsal plates less developed and rougher than the adult ones. Deutonymphs with the posterior epimeral plates with three ventral and one dorsal seta. Genital plate separated from other plates by membranous cuticle and bearing two pairs of setae and two pairs of genital acetabula underneath the plate, nearby a slit­like primordial genital opening. Among the twelve deutonymphs examined, four individuals with two pairs of blunt minute setae near the primordial GO have been found. Chaetotaxy: leg I, 1,2,7(III),5(II),9(III),6(I); leg II, 1,2,6,5,7,3; leg III, 1,2,3,3,5,3; leg IV, 0,1,3,3,5,3.
Protonymphs have their posterior epimeral plates with one ventral and one dorsal setae. Genital plate separated from other plates by membranous cuticle, with one pair of genital acetabula underneath the plate and no setae. Femur of leg IV undivided. Chaetotaxy: leg I, 1,2,5(II), 4 (II),5(II),6(I); leg II, 1,2,4,4,5,3; leg III, 1,2,2,3,5,3; leg IV, 0,2,3,5,3. Larva has its posterior epimeral plates with one ventral and none dorsal setae. Genital plate absent. Anterior epimeral plate with three pairs of ventral setae. Posterior epimeral plate with a single ventral seta. All femora undivided. Chaetotaxy: leg I, 1,4,4(II),5(II),6(I); leg II, 1,4,4,5,3; leg III, 1,3,3,5,3;
Etymology: Latin, Legione = a division of the Roman army, usually comprising 3,000 to 6,000 soldiers. The specific name is referring to the large amount of individuals which could be found at the same place on some of the beaches surveyed.
Remarks: A. legionium sp. nov. shares with nine species within the brevipalpus species group a set of features such as the presence of a blunt denticulate spur on third palpal segment; fourth palpal segment with two setae; tarsi II to IV with three dorsal and none ventral setae; tarsi III and IV with a spur­like lateral parambulacral seta; telofemur I with two ventral and two ventromedial spines; tibia I with one ventral and two ventromedial spines. Such species are: A. arabia Bartsch and Chatterjee, 2001, A. arborea Bartsch, 2003, A. atacamae Newell, 1984, A. borealis Newell, 1947, A. brevipalpus Trouessart, 1889, A. ibssi Bartsch, 1996, A. littoralis Bartsch and Iliffe, 1985, A. moorea Bartsch, 1992, A. ripa Otto, 1999, A. sordida Bartsch, 1992 (Bartsch, 2003a).
In A. legionium sp. nov., except by the claws of tarsus I, there are two rows of tines readily visible on lateral claws under 400 times magnification, instead the tines on claws of A. arabia, A. arborea and A. ibssi that are absent or only visible under oil immersion objectives. A. legionium sp. nov. has the spermatophorotype extending to and beyond the anterior edge of GA and a scaliform tectum instead a triangular tectum and a spermatophorotype that does not reach the anterior margin of GA, as found in A. brevipalpus. The tibia III­IV of A. legionium sp. nov. bear five setae, two bipectinate, instead three bipectinate setae on these tibiae, as it is found in A. littoralis, or four setae, as it is found in A. atacamae. Agauopsis atacamae also lacks a transversal bar in their areola on AD. Agauopsis littoralis has a length/width ratio on male's OC of 1.1 whereas A. legionium same ratio was found as 1.36–1.48.
A. legionium sp. nov. differs from A. ibssi by possessing a distinct raised area on PD. While A. sordida is characterized by its short rostrum which is 0.7 as long as the gnathosoma basis, A. legionium sp. nov. rostrum measures 1.18–1.36 times the gnathosoma basis. Males belonging to A. ripa have a rounded GA instead a truncate one. Outlying setae on GA are close to the external ring of perigenital setae in A. borealis whereas in the species described above they stand nearly midway between the crown of perigenital setae and the plate edge. A. moorea has gland pores on OC separated from its posterior cornea by twice its diameter while in A. legionium sp. nov. this distance measures almost the same than the cornea's diameter.
On its ecology, the species described here was found sometimes in large groups of individuals. Bartsch (1996) has reported the same on A. ibssi, a psammophilous species.
As cited earlier, among twelve deutonymphs examined, four have two pairs of minute setae on the edges of primordial genital opening. This feature could be observed on the genital plate of a deutonymph, which was containing a quiescent male whereas another deutonymph with a female quiescent was devoid of these setae. These evidences suggest the occurrence of sexual dimorphismus on the deutonymph of A. legionium.
description: Published as part of Pepato, Almir R. & Tiago, Cláudio G., 2005, Two new species of Agauopsis (Halacaridae, Acari) from Southeastern Brazil, pp. 1-12 in Zootaxa 994 on pages 5-11, DOI: 10.5281/zenodo.171392