SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9b88b126900beb62833f432d5342110c4b42e0abafe9bb255b9b3c922a6b6adb' 
  AND token = 'rD88BMB0hcnAvIoCXfUlq/VvvFQLYKZOJ/+AnqY4Acg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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