SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fc6eeef8c9afe220a677ad9de318d513343f7b2e2758df861b8e24ec346630fe' 
  AND token = 'ryHIPPS9PfEpBParfcOCEzZ2ycSKyIo3/XKKx6rPLDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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