SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8ad2b8cab227a13b819836cb3a64ba04d7b34947dddde5b53a4c23c4e5d4e1e8' 
  AND token = 'jy0QVIN9v9ULX7SG3znARXAh+6L6j5hUMfJ90KaTZVA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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