SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '84073aed69c918720ec4e9152bff49b7c8340e3327215bc0c805aa76329dffd1' 
  AND token = 'WM/z42SKmKlDclvXPDOnenow4HI+k+KGfU83xY8qdm0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00247

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}