SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2ad13b6332728af51bebbb67ada9a84940fd4452b53fa6576901c4f2f0bf246b' 
  AND token = 'UjCs+W79eTwwn6kGGRtrj/0PJsDQDeeiE5K/gIcBZMo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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