SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4436418a7cbe2bb69cf31ed7f745446e0746b5fd9e44378cff54c228a510db61' 
  AND token = 'kpYBW9YXcvp0JcBZF6uvIMXSUsDg1Xm/2tcbor/Hed4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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