SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48ec0c833955b293cce8e15661de86a76d8970f1be9f7400634d1bbd351c8a11' 
  AND token = 'IgjhA8cvZPkuRS7QFfatbqF8PjRAUHuco3JFLZAhM0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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