SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7d0327c626761decc1f52eda130e23fa2cd152b9bd6c76d3da52070b42c2ca24' 
  AND token = 'TgIszLBO8RMGarB6srH5yo9f8eJsmnoMT14fytaxcHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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