SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2a7920c4e068c7aa3ba7cdcdd7c94c68578c20f4d939431d0a4c77dffa3c27c1' 
  AND token = 'duyc8tloGbXskwHMDMjqHTmIvoxOeO6YIo7oGo4jIPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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