SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '234dd8b54f6d519ce5cfdff975a6159311b343dfd3b7ab8e485f2b42e640e22d' 
  AND token = 'UZgHUDhiaUh1pUmAj4TYFj3rq3fOtm0T1ii3WJ+smks=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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