SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cd3bd90c7abc5cdb17ce9538e3d36687444468f431cb0b9d662e9fef11816ca' 
  AND token = 'GUg1nF3517ORgw7EEFc3jNcAKDxZkk6sw5V9M+nF770=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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