SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c917629e9509bdfca4a2e83b21747b78934adf1d3a9d9eeee942198a8f79a90d' 
  AND token = 'ffADyhBBHjGhX+gmGuLWyYvlW/6hEd9EC3EuXnKvJXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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