Dipteropeltis Calman, 1912

Neethling, Lourelle Alicia Martins, Malta, José Celso De Oliveira & Avenant-Oldewage, Annemariè, 2014, Additional morphological information on Dipteropeltis hirundo Calman, 1912, and a description of Dipteropeltis campanaformis n. sp. (Crustacea: Branchiura) from two characiform benthopelagic fish hosts from two Northern rivers of the Brazilian Amazon, Zootaxa 3755 (2), pp. 179-193 : 183-185

publication ID	https://doi.org/ 10.11646/zootaxa.3755.2.4
publication LSID	lsid:zoobank.org:pub:44846DB8-02B4-4806-9B11-CAD57E716650
DOI	https://doi.org/10.5281/zenodo.6143743
persistent identifier	https://treatment.plazi.org/id/03DBB164-FFD0-8C53-0191-E2F008B0F326
treatment provided by	Plazi
scientific name	Dipteropeltis Calman, 1912
status

Treatment

Dipteropeltis Calman, 1912 View in CoL

( Figure 1 View FIGURE 1 , 2 View FIGURE 2 , and 3A)

Dipteropeltis hirundo Calman, 1912

Material examined. Paratypes. 6 egg-bearing ♀: 1 egg-bearing ♀ ( BMNH 1892.10.24.2) collected from Salminus brasiliensis (Cuvier, 1816) from Corumbá, Mato Grosso, Brazil during October 1892; 1 egg-bearing ♀ ( USNM 41866) collected from an unknown host caught in Buenos Aires, Argentina during October 1899; 1 egg-bearing ♀ ( INPA 429) collected from Acestrorhynchus falcirostris (Cuvier, 1819) from Rondônia, near Costa Marques, Brazil during November 1983; 2 egg-bearing ♀ ( INPA 430i, ii) collected from Salminus brasiliensis (Cuvier, 1816) from Minas Gerais, Brazil during September 1985; 1 egg-bearing ♀ ( MLP Cr 26049) collected from Luciopimelodus pati (Valenciennes, 1835) from Rosario, Argentina during October 1941 (see Table 1).

Description. In dorsal view ( Fig. 1 View FIGURE 1 A), D. hirundo has a wide, rounded head shield. A pair of separate interocular rods (ir) originates between the compound eyes (ce) and extend towards the nauplius eye (ne). The carapace lobes exceed the length of the abdomen and thus form the total length of the species (HC, Fig. 1 View FIGURE 1 A, 1B, Table 2) with a range of 6–25.5 mm (average of 14.4 mm), and the average split length (CSL) of the carapace (i.e. the depth of the sinus of the carapace) is at 84.67 % of the length of the carapace (CSL/HC, Table 2). The network of branching ducts of the midgut is visible in both light microscopy and scanning electron microscopy, and reaches the external margins of the carapace. The carapace lobes shield the abdomen from view dorsally.

In ventral view ( Fig. 1 View FIGURE 1 B, 3A), the head shield is round and folds in towards the appendages of the cephalon. These folds exceed the outer margins of the maxillules (mx). If the head shield were to be folded open, the folds would invariably form a square-shape. Respiratory areas were not visible in light microscopy but a large respiratory area was visible in scanning electron microscopy ( Fig. 2 View FIGURE 2 A).

The antennules and antennae were not observed as these structures were obscured by both the head shield and the maxillules; and furthermore did not survive the micro-dissection during the scanning electron microscopy study. However, Møller & Olesen (2010) provided micrographs and a schematic drawing in Figures 2 View FIGURE 2 B–D.

The maxillule (mx, Fig. 1 View FIGURE 1 B) rim is divided into three zones; zone 1 (interior margin) bears folds in an erratic pattern ( Fig. 2 View FIGURE 2 B); zone 2 (middle zone) is the widest zone and bears round sclerites with minute setules arranged within it ( Fig. 2 View FIGURE 2 C, D); zone 3 (exterior margin) bears a single border of setules. The maxillules have a diameter that ranges between 0.05–1.00 mm ( Figure 1 View FIGURE 1 B, Table 2), and occupy an average of 4.10 % of the total length of the specimens (SD/HC, Table 2).

The mouth (mo, Fig. 1 View FIGURE 1 B) is borne on a long and slender siphon-like cone. The labrum (labr, upper lip) has an inverted U-shape, and is joined laterally with the labium (labi, lower lip). The labium therefore does not exceed the limits of the labrum, and forms the posterior limit of the mouth (see Møller & Olesen 2010, Figure 3 View FIGURE 3 A–E). Neither the labial spines, nor the mandibles with their denticles or the preoral papilla and sting were discernible during the light microscopy study but these are shown in Møller & Olesen (2010) Figure 2 View FIGURE 2 E and 3.

The maxillae (ma, Fig. 1 View FIGURE 1 B, 1C) are uniramous, six segmented, with the last three segments at an angle to the basal three segments. The maxillae appear hooked and are adorned with scales and setules as is shown in Møller & Olesen’s (2010) Figure 5 View FIGURE 5 A.

The natatory lobe (nl, Fig. 1 View FIGURE 1 D) of the fourth pair of swimming legs is elongate and rounded, almost tongueshaped, with a small protrusion at the base of the lobe that in some specimens resembles a fold of exoskeleton.

The abdomen lobes (AL, Fig. 1 View FIGURE 1 B) range between 3.0– 8.5 mm in length (see Table 2) with blunt tips that lie in an inverted V. The abdomen length (AL) forms an average of 35.33 % of the total length (HC) of the species (AL/ HC, Table 2). The abdomen split length (ASL), that is the depth of the sinus of the abdomen, is an average of 81.0 % of the length of the abdomen (ASL/AL, Table 2). Two minute round furcal rami (fr, Fig. 1 View FIGURE 1 B) are situated on the abdomen in the angular split. The spermathecae (sp, Fig. 1 View FIGURE 1 B) are oval and the area is raised and adorned with scales.