SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '48127c2f2ca65cb71bbf582144a1bfa2502f7a1e844c95e49209a9b846961cde' 
  AND token = 'hmB3TNfRufaLLtotGHyWWNOeds0hxw0SzrIQ54mMRo8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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