SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd42696d6b44543673ce97221749251bedc45c00845c82e9aa66607c96eb69f5' 
  AND token = 'cYp5OZlZzevdUzdzmv0gJRXzWtiZESinaKT2oNJ7VDk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00084

JSON explain

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