Marvel has come under heavy fire over a cover for its forthcoming Spider-Woman series by an artist known primarily for his erotic art. The cover shows the superhero in what is being described as a "blatantly sexualised" pose, and "a prime example of why people continue to think superhero comics are for horny men only".

Announced at Comic-Con in San Diego last month , as part of a "Women of Marvel" panel, the new series, by author Dennis Hopeless and artist Greg Land, is set to debut in November, starring Jessica Drew as Spider-Woman. A variant cover for the first comic in the series by the artist Milo Manara, reputed for his erotic illustrations, was revealed by the news site Comic Book Resources earlier this week. The cover shows Jessica – according to publicity for the series, "a woman with a mission" who "just won't abide … being a target" – on all fours, in a skin-tight red outfit.

It drew immediate and scathing criticism. "If you're wondering what the hell Jessica Drew, aka Spider-Woman is doing, I believe it's what's known in the animal kingdom as 'presenting'," wrote science fiction site io9. "She looks like she's wearing body-paint, and that's a big no-no for an industry still trying to remember that women exist and may perhaps read comics and also don't want to feel completely gross when they do so. As for the position she's in … Christ … Here's a simple rule: If it's inappropriate for a male character, it should also be inappropriate for a female character."

Laura Sneddon, a comics expert who blogs at comicbookgrrrl, told the Guardian that "women do love superhero comics, and we even love a bit of cheesecake here and there, but this cover and the lack of thinking behind it is a prime example of why people continue to think superhero comics are for horny men only".

"I think it's a really disappointing decision by Marvel editorial to choose this kind of artist for a variant cover on a female-lead comic. There's a time and a place for Milo Manara's style of work, but it's in erotic comics rather than superhero comics, or at least he could be asked to reduce the sexualised lens for this very different audience," said Sneddon.

Rich Johnston at comics site Bleeding Cool called it the "Cover That Will Launch A Thousand Headlines", adding: "Remember folks, this was the comic that was launched at the Women Of Marvel Panel at San Diego Comic Con. It's almost as if Marvel are doing this on purpose now."

Pop culture site the Mary Sue added that "anyone familiar with pornography knows this pose … ripped straight from the fantasy medium", pointing out its similarity to one Manara had already drawn in an Italian erotic comic.

"This is what we talk about when we ask comic publishers not to actively offend their paying (or potentially paying) customers," wrote the Mary Sue's Jill Pantozzi. "It's important to note, Manara is known for erotic art, and there's absolutely a place for that. But was he the best choice to promote this particular comic? I would say unequivocally no."

Marvel has yet to respond to requests for comment, but Hopeless, who is writing the new Spider-Woman series, told fans on Twitter that: "I can promise you we have no intention of blatantly sexualizing any of the characters in our story", and "I don't have any input at all on covers. You have my word that our story treats Jess with the utmost respect".

Marvel has recently moved to attract more female readers to its publications, earlier this summer announcing that the new comic series about its character Thor would recast the Norse god as a woman.

"The new Thor continues Marvel's proud tradition of strong female characters like Captain Marvel, Storm, Black Widow and more," the publisher said at the time. "And this new Thor isn't a temporary female substitute – she's now the one and only Thor, and she is worthy!"

Sneddon said that Marvel had been making "great strides this year in making their comics appeal more to women readers", pointing to titles including Ms Marvel and Storm, "all featuring women with a great reception from comic fans, including many new readers". Ms Marvel, she said, went through six printings just to keep up with the demand for the new character Kamala Khan.

"But while diversity on the page has improved, diversity behind the pens really hasn't," said Sneddon. "There still just aren't enough women breaking into the superhero comics industry, and covers like these help illustrate why – they put up a very big 'no women welcome' sign, which puts off not only women readers, but the many women creators working on a great variety of other comics."