The family Opilioacaridae (Parasitiformes: Opilioacarida) in Mexico, description of two new species and notes on biology and geographical distribution Author Vázquez, Ma. Magdalena Author Klompen, Hans text Zootaxa 2015 3957 5 535 552 journal article 10.11646/zootaxa.3957.5.3 ee824d67-1777-4c76-a6e2-b84ae31cd893 1175-5326 245496 0F55F39A-4BB0-47F0-85C9-F458CAEE81C6 Neocarus texanus Chamberlin & Mulaik 1942 ( Fig. 1 C, 3C, 6C, 7C) Material examined: 4 females and 1 male . Description focusing on additions to, and differences with, the re-descriptions of N. texanus from Texas by Van der Hammen (1966) and Vázquez & Klompen (2002) . States from those studies listed in square brackets. Gnathosoma. Movable digit chelicera ( Fig. 1 C) with 1 large and 2 very small ventral denticles [just 1 large]. Palp trochanter with 3–6 ribbed, tapering setae (= r - type ); femur with 6–9 papilliform (= p - type ) and 12–15 r - type ; genu with 6 p - type and 26 r - type setae; tibia with 26 r - type and 35 lightly serrate and pointed setae. Palp tarsus ( Fig. 3 C) with 5 foliate ( d ), 7–8 [8] v , 10–14 [14, 21] ch , and 9–10 [6, 8] sm setae, plus 3 solenidia. Tarsal lyrifissures i π and i α present. Subcapitulum with 4 [5] circumbuccal ( cb ) and 8–10 [6–7] median and subcapitular ( vm , lvm , ldm , vp , lvp ) setae. Females have more setae (9–10) than males (8). Idiosoma. Prodorsal shield in adults with 86 (M)–95 (F) [108–125] stout, ribbed setae, and 1 pair of lyrifissures. Anal plates each with 7–8 (9–10) stout, ribbed setae. Sternal verrucae in adults ( Fig. 6 C, 7C) each with 1–3 [2–4] ribbed, tapering, and 1 long, composite ( st1 ) seta. Remaining sternal region with 5–7 [4–6] pairs of stout, ribbed, blunt-tipped setae and, centrally, 2 pairs of ribbed, tapering setae ( st2 , st3 ). Pregenital capsules each with 1 long, tapering seta and 3–4 [3–4M 5–6F] stout, ribbed setae. Pregenital and genital areas in male with, respectively, 6 [4–5] stout, ribbed, blunt-tipped and 8 [8–9] ribbed, pointy-tipped setae [fine]. Pregenital area in female with 2 [2] short, stout, ribbed setae, genital area nude. Ovipositor without terminal setiform sensilla or spine-like internal structures, but with 3 pairs of channels. Males with one pair of unusually large glands and one much smaller pair. Legs. Legs moderately long. Length legs I–IV in adults ( 1 male , 1 female ), respectively, 3194–3383, 1607– 1644 , 1663–1739 , and 2495–2589 µm. Ratio of legs I to idiosoma in adults 1.7–2.2 [2.1], legs IV to idiosoma 1.3– 1.7 [1.8]. Tarsus I without distinct acrotarsus. Sensillum with “crown-like” tip in main sensillar field. Coronidia limited to the basal 2/3 of basitarsi II–IV. Distal solenidion ω d on basitarsi II–IV indistinct or absent [observed on legs III by Van der Hammen (1966) ]; basal solenidion ω p distinct. Deposition of specimens . One female ( CNAC 007219) and one male ( CNAC 007220) at CNAC ; other specimens at OSAL , UQROO . Material examined . Due to their size, individual specimens may be represented by multiple slides (as indicated). Mexico , Guerrero, Cumbre de Llano Largo, Mpio. Puerto Marquez, near coast close to Acapulco, 371m , 18.8251N 99.8333W ; 19-Jun-2007 ; coll. Montaño, H.; ex litter under shrubs in tropical deciduous forest; coll. event no. CNAC 005974: F, CNAC 007219 (4 slides); F, OSAL 0 105705 (3 slides); F, OSAL 0 105709 (3 slides); F, OSAL 0 105712 (3 slides); M, CNAC 0 0 7220 (3 slides). Taxonomic remarks. These specimens differ from N. texanus by the slightly smaller number of prodorsal shield (86–95 vs. 108–125 in N. texanus ), and anal valve (7–8 vs. 9–10 in N. texanus ) setae, and the common presence of a distinct distal solenidion ω d on basitarsi II–IV and absence of a distinct basal solenidion ω p (respectively indistinct and distinct in N. texanus ). These differences are either small quantitative differences, or concern structures that are often very difficult to observe (leg solenidia). Given the relatively small sample size of available specimens from both Texas and Acapulco these differences are considered insufficient for specific status.