SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'efcd63a69d6b6e7a8d106fc0dc09edd9f96c2d574e17459b95ee752cd84bc536' 
  AND token = '84nUIfLRNo6f2Oqa34FyHqBGwjRBNRAtWHw2y/M/+yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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