SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6b6f8781cfbdc5f8b040360b70654a6f1421b2e5efc976f3dbdac02e511276e6' 
  AND token = '6XUbnTTdV7blSijjiRfxGhtlKu+Fdg5/mzi6GHBqEpw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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