SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '846e01f5218f56cf5fb63a3ddb3be91467d4b946fce4527febee7597892006aa' 
  AND token = '8yhXzJ7cvwGCjHdhiO7+B4guqouCHfqQqQsYKOKZWgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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