SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '74fb7d15d240a84c4ad696bbf88fe15532fd34cf697c31ed2c687c457835b6c8' 
  AND token = '1OmBhjDxqU55wKpFIvg7bnhujmEDR+17gjSvxqGVpd4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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