SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef431d6315e60b7f3f4cc27c96e379f4f769627a0290472c2e877e519db83574' 
  AND token = 'sJ/BO3BvK/j+wB4z+eLLr5uCc/dPKmhVrH11VayLUl8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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