SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccb008d85dc573ac96d7f636f396db116a9fc6ec7754b6935b8610b12cd806a9' 
  AND token = 'itoH4lDXZzmQIj/B1mS89pkh7ia++xCvLVKAJB58UUc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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