SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28fdcf2b922d88b3004bcb32271861efb2d527d926c5957a8fddb183dfb5b8f8' 
  AND token = 'ZGGlRTgX+puXq5sCeprDKq7LdXroAdCbFhiLDu2DU1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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