SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e98de8da604b1b576f62414cb7b95f3236e49366895146c727708e8962263733' 
  AND token = 'GvMIvmTZAXYPRNw2DbZYdFnnETZd5wLzvWh1isHV1ak=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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