SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c325e105e35b23f09f217dd62fd00fe9bb931d9996fa3faf41f919ee303799ac' 
  AND token = 'kGdyeopO7vBf/QXsEnaeeNDgOBYJf9iNlRinFVOczNM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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