SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0a2772128b49c51a0296389da02c76cc35cf1e2a4d9383f2fbf86bbc4afcd96b' 
  AND token = 'fnKwmZIi49ImYiEDLc49TqNF5IfvdoYNr9ZjPd/JYZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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