SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3fa357367e7d1ac3afb229a43efacbdbbc52e8bbc246eb345761d5e5dfef63ed' 
  AND token = 'am+k+cAuWi134QLCUwuGtXe5kt/npGx0YyNmqlp19UY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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