SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2cccc0f5490750efba9cadb1f19d4858c0ef440ed56ce38af9b0c22cb56af620' 
  AND token = 'Twi98Kjv0v1Y6rWykrBRB5fHJHMIviHdywBAWh9BLug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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