SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '310e78319fa31638d7070d04a3ad679fd186a40c95c5ee58b260f227ed34d7f4' 
  AND token = 'QIYNtDFGCfBCQdcy6fXDc5GNVsgQogh2HmZhPHnCDq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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