Aspidoras rochai Ihering, 1907

Tencatt, Luiz Fernando Caserta, Britto, Marcelo R., Isbrücker, Isaäc Jan Hendrik & Pavanelli, Carla Simone, 2022, Taxonomy of the armored catfish genus Aspidoras (Siluriformes: Callichthyidae) revisited, with the description of a new species, Neotropical Ichthyology (e 220040) 20 (3), pp. 1-159 : 137-141

Aspidoras rochai Ihering, 1907

( Figs. 72–73 )

Aspidoras rochai Ihering, 1907:30–35 (original description; type locality: Fortaleza, Ceará State, Brazil). — Eigenmann, 1910:402 (listed). —Miranda Ribeiro, 1911:155 (description, after Ihering, 1907). —Miranda Ribeiro, 1918:720 (listed, apparently the syntypes; Fortaleza). —Fowler, 1954:46 (references, in part). — Britski, 1969:206 (brief description; designation of the lectotype). —Menezes, 1994:220 (correction of the type locality to Guaramiranga, Ceará, Brazil). —Nijssen, Isbrücker, 1976:110–111 (identification key; redescription). — Britto, 2000:1054 (listed as comparative material; partim). — Lima, Britto, 2001:1015 (listed as comparative material; partim). —Reis, 2003:292 (listed). —Ferraris, 2007:10 (listed). —Wosiacki et al., 2014:311, 315 (morphological comparison; listed as comparative material). —Oliveira et al., 2017:e160118[3], e160118[7] (morphological comparison; listed as comparative material). —Tencatt, Bichuette, 2017:8–9, 21 (morphological comparison; listed as comparative material).

Diagnosis. Aspidoras rochai can be distinguished from all of its congeners by having preadipose azygous plates with variable sizes, alternating between smaller and larger plates (vs. preadipose azygous plates generally with similar sizes; anteriormost plates smaller than remaining plates in some specimens), and by the presence of a light and somewhat irregular stripe on middle portion of the dorsolateral body plates, which runs parallel to flank midline, from the region just anterior to dorsal fin to the caudal peduncle, being united with the stripe of the other side of the body in the predorsal region (vs. absence of such stripe). Additionally, it can be distinguished from A. aldebaran , A. belenos , A. depinnai , A. poecilus , A. psammatides , A. raimundi , and A. velites by having relatively wide frontal bone, with width equal to or slightly larger than half of entire length (vs. narrow, with width slightly smaller than half of entire length in A. aldebaran , A. belenos , A. depinnai , A. poecilus , A. raimundi , and A. velites ; extremely narrow, with width conspicuously smaller than half of entire length in A. psammatides ).

Conservation status. Aspidoras rochai is currently known only from its type locality,

the Guaramiranga region in Ceará State, which remains vague even after the correction proposed herein (see Remarks below). Considering that the only available material of this species remains restricted to the two type specimens even after this comprehensive review, and that there is no information on distribution, population trends, or threats ,

it is not possible to adequately assess the risk of extinction of the population. According to the International Union for Conservation of Nature (IUCN) categories and criteria

(IUCN Standards and Petitions Subcommittee, 2019), Aspidoras rochai can be classified as Data Deficient (DD).

Remarks. According to Ihering (1907:34), Aspidoras rochai , the type species of the genus, was described based on two specimens from Fortaleza, the capital of Ceará State,

Brazil. However, Menezes (1994:220) mentioned that Francisco Dias da Rocha, the collector of both type specimens, informed that, in fact, these specimens were captured in Guaramiranga, also in Ceará State, and not in Fortaleza. The region of Guaramiranga is drained by tributaries to the rio Aracoiaba , itself a tributary to the rio Choró , which quite possibly is the drainage from where these specimens were captured, though no water body was mentioned by Menezes (1994). Therefore , based on Menezes’s (1994)

statement, the type locality of Aspidoras rochai is herein corrected to Guaramiranga,

Ceará State, Brazil. Although it was possible to analyse both type specimens of A .

rochai, no additional specimens matching them were found. Since the core of the

Corydoradinae taxonomy relies on osteology plus color pattern, it was not possible to gather significative additional information from the two old and damaged type specimens when compared to the first review by Nijssen, Isbrücker (1976). Therefore,

no redescription of A. rochai is provided herein. In the same way, all putative diagnostic features gathered here are derived from the analysis of the external morphology of the two type specimens. A proper evaluation of A. rochai awaits the future analysis of new material, especially CS specimens.

In spite of the limited information obtained from both type specimens, it was possible to differ A. rochai from its congeners by its apparently unique pattern of preadipose azygous plates and relatively wide frontal bone (see Diagnosis). Aspidoras rochai shares a relatively wide frontal with A. albater , A. azaghal , A. fuscoguttatus , A. mephisto , and A. lakoi . Aspidoras rochai differs from A. albater , A. azaghal , A. mephisto , and A. lakoi by having anterior portion of infraorbital 1 with at least well-developed laminar expansion, surpassing middle of nasal capsule (vs. expansion ranging from strongly reduced, at same level as posterior margin of nasal capsule, to moderately developed, reaching middle of nasal capsule in A. albater ; moderately developed, reaching middle of nasal capsule in A. azaghal ; ranging from strongly reduced, not reaching or at same level as posterior margin of nasal capsule, to moderately-developed expansion, reaching middle of nasal capsule in A. mephisto ; ranging from poorly developed, slightly surpassing posterior margin of nasal capsule, to moderately developed, reaching middle of nasal capsule in A. lakoi ). Considering that Aspidoras species often present the anteroventral portion of infraorbital 1 covered by a thick layer of skin and the difficulty in clearly delimiting the nasal capsule in non-CS specimens, the analysis of CS specimens may eventually reveal that A. rochai presents anterior laminar expansion of infraorbital 1 extremely well developed.

Although A. fuscoguttatus is the most similar congener to A. rochai , considering only the few external osteological information observed herein, it was possible to separate the two species based on the pattern of preadipose azygous plates and also by the unusual color pattern of A. rochai (see Ihering, 1907:32), which is characterized by the presence of a light and somewhat irregular stripe on middle portion of the dorsolateral body plates, running parallel to the “lateral line” (presumably the flank midline) from the region just anterior to dorsal fin to the caudal peduncle, being united with the stripe of the other side of the body in the predorsal region. In the original bilingual publication, the Portuguese version of the A. rochai description (Ihering, 1907:33) curiously presents small differences from the English version, such as the presence of a light blotch on the region in which the stripes from both sides of the body are fused. Additionally, the author also indirectly refers to the presence of what seems to be a “lower stripe” in the Portuguese version, comparing its intensity of pigmentation in relation to the stripe slightly above midline of flank. Ihering (1907) made no further reference to this “lower stripe”. Anyway, the aforementioned pattern is not present in A. fuscoguttatus .

Material examined. Same as listed by Nijssen, Isbrücker (1976:110).

Figures

FIGURE 72 | Aspidoras rochai, lectotype, MZUSP 2195, 38.7 mm SL, Guaramiranga, Ceará State, Brazil. Dorsal (top), lateral (middle) and ventral (bottom) views. Photo in lateral view by Eduardo Baena.

FIGURE 73 | Aspidoras rochai, paralectotype, MZUSP 5300, 35.5 mm SL, Guaramiranga, Ceará State, Brazil. Dorsal (top), lateral (middle) and ventral (bottom) views.