SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef6fb7add54e2132ed8db2e9c6bd6664ede1f191cb333a65179660d5c3e35e91' 
  AND token = 'yoAcRYkrCs4ov+iSC2sJ3EOImvmMxojT29lXUxlU3fA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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