SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd7fea79f71f6e50e0775e366da9fbefae011fee21f16ea80936342911dd205a6' 
  AND token = 'iGuxgsInbCHtW99eUYBDsw3NNeU5S95NbSHU8tcPgQE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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