SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3bcc9546dc232d63a7551e1c8a8353f819dce1a111d6f581e61d915d91ab970' 
  AND token = 'yzKk6bb6i5dqeZ2L60caqFnXkFJov3TwFKr2Oj3pYaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}