Caecopactes chullachaqui Campos-Filho, Sfenthourakis and Bichuette, 2023

Campos-Filho, Ivanklin Soares, Sfenthourakis, Spyros, Gallão, Jonas Eduardo, Senna-Horta, Lilia & Bichuette, Maria Elina, 2023, The first troglobitic terrestrial isopod (Isopoda, Oniscidea) from Peru, Nauplius (e 2023003) 31, pp. 1-12 : 5-7

publication ID	https://doi.org/ 10.1590/2358-2936e2023003
publication LSID	lsid:zoobank.org:pub:1455465B-8F89-4A1E9328-6BE20F32F052AB
DOI	https://doi.org/10.5281/zenodo.10914240
persistent identifier	https://treatment.plazi.org/id/7F3C4745-1642-FFEF-FCA4-361B9CD90014
treatment provided by	Felipe
scientific name	Caecopactes chullachaqui Campos-Filho, Sfenthourakis and Bichuette
status	sp. nov.

Treatment

Caecopactes chullachaqui Campos-Filho, Sfenthourakis and Bichuette View in CoL sp. nov.

( Figs. 1 – 5 View Figure 1 View Figure 2 View Figure 3 View Figure 4 View Figure 5 )

http://zoobank.org/ urn:lsid:zoobank.org:act:C0F77BDF-BFE8-4764-A656-B9164D7505B2

Type material. Holotype: male adult ( MUSM-CRUS 0100000 ), Peru, San Martin, Rioja, Nueva Cajamarca, Cueva de Palestina, 5º52’33”S 77º20’51.31”W, 900 m a.s.l., 9 Sep 2016, leg. M.E. Bichuette, J.E. Gallão and L.S. Horta, specimens on decomposing organic material GoogleMaps . Paratypes: one male (parts in micro-preparations), three females (one in micro-preparations) ( MUSM-CRUS 0100001 ), same data as holotype GoogleMaps ; one male, two females ( LES 27969 About LES ), same data as holotype GoogleMaps .

Description. Maximum body length: male and female 9 mm.

Body pigments and eyes absent.

Body ( Fig. 3A View Figure 3 ) strongly convex; dorsum smooth bearing triangular scale-setae ( Fig. 3B View Figure 3 ). Pereonite 1 epimera laterally rounded, anterior corner not surpassing distal margin of cephalon; pereonites 2 and 3 epimera rounded, 4–7 subquadrangular; pleonites 3–5 epimera with continuous outline with that of pereonite 7 ( Fig. 3A, F View Figure 3 ); pereonite 1 epimera not grooved laterally, ventral lobe slightly surpassing outer lobe of schisma; pereonite 2 epimera without ventral lobe ( Fig. 3G–J View Figure 3 ).

Cephalon ( Fig. 3C–F View Figure 3 ) with lateral lobes welldeveloped and directed outwards; frontal shield fused with vertex; linea suprantennalis absent; lamina frontalis with 2 lateral rounded lobes (visible under light microscopy); lateral margins depressed to accommodate anterior corner of pereonite 1 epimera.

Pereonites 1–7 epimera ( Fig. 3G, I View Figure 3 ) bearing 1 line of noduli laterales per side at same distance from lateral and posterior margins.

Pleonites 3–5 epimera ( Fig. 3K View Figure 3 ) rectangular, epimera 5 surpassing distal margin of telson.

Telson ( Fig. 3K View Figure 3 ) triangular, lateral sides almost straight, distal margin broad, not covering uropods.

Antennula ( Fig. 3L View Figure 3 ) with distal article longest bearing 8 aesthetascs in 4 rows plus apical pair.

Antenna ( Fig.3M View Figure 3 ) not surpassing posterior margin of pereonite 1 when extended backwards; flagellum distal article about 3 times as long as proximal article bearing lateral aesthetascs.

Left mandible ( Fig. 4A View Figure 4 ) with 2+1 penicils, right mandible ( Fig. 4B View Figure 4 ) with 1+1 penicils.

Maxillula ( Fig. 4C View Figure 4 ) inner endite with distal margin rounded covered with thin setae;outer endite composed of 3+4 simple teeth.

Maxilla ( Fig. 4D View Figure 4 ) inner lobe rounded and covered with thick setae; outer lobe twice as wide as inner lobe and covered with thin setae.

Maxilliped ( Fig. 4E View Figure 4 ) basis rectangular; palp proximal article bearing 1 seta; endite rectangular, medial seta stout.

Pereopods 1–7 ( Fig.5A, B View Figure 5 ) gradually increasing in size, merus and carpus 1–7 bearing sparse setae and hyaline fringe of scales on sternal margin; carpus 1 with distal seta with double-serrate apex, antennal grooming brush longitudinal reaching about half of its length; dactylus with dactylar and ungual setae simple.

Uropod ( Figs 3K View Figure 3 , 4F, G View Figure 4 ) protopod triangular and elongated, endopod twice as long as exopod bearing several distal setae;exopod inserted on medial portion bearing several distal setae.

Male: Pereopod 7 ( Fig. 5B View Figure 5 ) ischium with sternal margin concave. Genital papilla ( Fig. 5C View Figure 5 ) with elongated triangular ventral shield and distal papilla bearing subapical orifices. Pleopod 1 ( Fig. 5D View Figure 5 ) exopod sub-trapezoidal, proximal margin straight, distal and lateral margins rounded; endopod 4 times as long as exopod, distal portion tapering, apex bent outwards bearing small setae on median portion. Pleopod 2 ( Fig. 5E View Figure 5 ) exopod triangular, outer margin concave bearing 3 small setae; endopod flagelliform longer than exopod. Pleopod 3 exopod ( Fig. 5F View Figure 5 ) triangular, outer portion rounded, outer margin concave bearing2 setae. Pleopod4 exopod ( Fig.5G View Figure 5 )rhomboid, proximal outer corner depressed, outer margin sinuous bearing 5 small setae. Pleopod 5 exopod ( Fig. 5H View Figure 5 ) triangular, proximal outer corner depressed, outer margin slightly convex bearing 4 setae, inner margin slightly grooved to fit distal portion of endopod 2.

Etymology. The new species is named after the Peruvian Amazonian myth ‘El Chullachaqui’. In Quechua native language, chulla = unlike, and chaqui (pre-Hispanic Peruvian) = foot. The Chullachaqui is a dwarf who inhabits the mountain forests of Amazon and can transform into any animal or person. It is also known as the guardian of the rainforests, taking care of the animals and plants from hunters.

Habitat. The specimens were collected in decomposing organic matter and guano in the aphotic zone.

Remarks. Caecopates chullachaqui sp. nov. differs from C. minimus in having a cephalon lamina frontalis with protruding lateral corners (vs. not protruding in C. minimus ), antennal peduncle with fourth and fifth articles not triangular shaped (vs. triangular shaped in C minimus ), maxillula outer endite with the outer set of teeth simple (vs. maxillula outer endite with outer set bearing two teeth apically cleft), male pleopod 1 endopod with distal portion bent outwards (vs. straight in C. minimus ), male pleopod 2 exopod elongated (vs. short in C. minimus ), and male pleopods 4 and 5 exopods with outer proximal portion depressed (vs. not depressed in C. minimus ).