SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a59756acd1b7a4a0a25e83c784881eeb84dcbe45037fec7f3d4f6ed37c6049d' 
  AND token = 'V2jC7rluwDIWaNLsRMzJOZhNAX57iPPOBVAqTbVdqFA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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