SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1cd1948d6656b8ad7fe7e5918ec0846b45bee1c3c0da16a961ef2b5be402875b' 
  AND token = 'Nkp/KEU3q3q49uXFohiAjf0JNqVC2Nm9D4AiuKvTJmQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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