SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd94342a12444ebcc8e447bfb2605f47bb54ff11357905839be78f5153fbc7691' 
  AND token = 'YaC1WiBmzhjpJOd9p8UnV/lC7lDS6Bdst2w+l6tRqeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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