Herpyllobius pabloi Suárez-Morales and Salazar-Vallejo, 2025

Herpyllobius pabloi Suárez-Morales and Salazar-Vallejo View in CoL sp. n.

( Figures 10 View Figure 10 , 11 View Figure 11 )

Material examined

Adult ovigerous female holotype from Harmothoe sp. , Expedition MADEEP, NW Kavieng, RV Alis, Sta . CP4255 ( 02°27 ʹ 55.1988” S, 150°43 ʹ 33.5928” E) ( MNHN-IU 2023-503 ), 333–420 m, in wood, 24 April 2014, L GoogleMaps . Corbari and S GoogleMaps . Samadi, leg.

Type locality

Kavieng, RV Alis, Sta. CP 4255 ( 02°27 ʹ 55.1988” S, 150° 43 ʹ 33.5928” E) ( MNHN 2015–1870), depth = 333– 420 m.

Etymology

The species is named after Dr Pablo López-González (Universidad de Sevilla, Spain) for his relevant contributions to the taxonomic knowledge of herpyllobiid copepods.

Diagnosis

Herpyllobius with female ectosoma roughly oviform, ectosoma expanding towards genital area. Ectosoma whitish except for darker, lightly brownish genital area. Genital area with pair of prominent swellings with attached egg sacs. Genital swellings separated by flat intergenital surface; intergenital surface with four minute sclerotised dots and low, volcano-like medial protuberance. Ectosomal integument translucent, lightly wrinkled. Ectosoma and endosoma connected by short stalk originating on underside of ectosoma. Endosoma with proximal mass expanding into two unequally long, cord-like processes, longest process about 0.7 times as long as ectosoma. Egg sacs thick, slightly curved, about 2.5 times as long as wide, multiseriate, with 6–8 rows of eggs.

Description of holotype adult female

Ectosoma ovoid, 1.2 mm at maximal posterior height, 710 μm high at anteriormost section; ectosoma 1.65 mm long. Ectosomal integument whitish, with thin, translucent, lightly wrinkled integument ( Figures 10 View Figure 10 (B), 11(F)). Genital area brownish, with pair of heavily sclerotised, ring-shaped genital swellings (diameter = 180 µm, height = 120 µm each) ( Figures 10 View Figure 10 (A), 11(F), gs); intergenital area flat, with 4 sclerotised integumental dots ( Figure 10 View Figure 10 (A), arrowheads) and adjacent volcano-like medial protuberance between genital swellings ( Figure 10 View Figure 10 (D), arrowhead). Genital swellings with attached egg sacs ( Figure 11 View Figure 11 (F), es).

Holotype carrying 2 egg sacs, one detached during handling. Egg sacs thick, cylindrical, weakly curved, 1.6 mm long, 0.82 mm wide ( Figure 11 View Figure 11 (F), es); eggs 65–85 μm in diameter. Intersomital stalk short, thick, ca. 130 μm in diameter, originating close to mid-body underside ( Figure 10 View Figure 10 (B), stk). Endosoma of holotype 1.3 mm long, with 2 sections, proximal half umbrella-like, with jagged edges. Distal half with 2 unequally long, cord-like lobes ( Figure 10 View Figure 10 (C), arrowheads).

Remarks

This new species infecting Harmothoe sp. is assigned to Herpyllobius Sars, 1870 because of its possession of the distinctive characters mentioned by López-González et al. (2006) and Boxshall et al. (2019), including having an ovoid ectosoma, with a pair of sclerotised, prominent genital openings, with 4 sclerotised dots in the intergenital surface, stalk originating close to midline on the underside of ectosoma, and endosoma with digitiform lobes, attached adult males with unsegmented body.

The specimen found on Harmothoe sp. from New Guinea closely resembles the widespread H. polynoes (KrØyer, 1863) , because of its possession of the following important characters of this species (see Lützen 1964a): (1) ovoid ectosoma, (2) prominent sclerotised genital swellings, (3) 4 minute sclerotised dots between the genital swellings, (4) thick, ovoid, multiseriate egg sacs, (5) medial volcano-like protuberance adjacent to the sclerotised dots, (6) attachment to the dorsal part of the host prostomium, (7) preference of Harmothoe species as hosts. However, our specimen diverges from H. polynoes in some important respects: (1) the absence of minute cuticular formations close to the genital swellings, on the underside of the ectosoma, is a character particular to this species (Lützen, 1964, fig. 5); and (2) the shape, size, and structure of the endosoma, which is invariably flattened, tongue-shaped and about 3 times as long as the endosoma in H. polynoes , as described and depicted by Lützen (1964), but it is elongate, not flattened in the new species H. pabloi . In addition, Lützen (1964a) noticed that H. polynoes usually occurs on species of Harmothoe and in most cases with only one copepod individual, as recorded for H. pabloi in our material from New Guinea. Herpyllobius polynoes is largely restricted to Arctic and subarctic latitudes (Lützen, 1964), thus diverging from H. pabloi sp. n., a closely related species found in subtropical waters of the Southern Hemisphere.