SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e0416253ad912e72326b3e7a31c8feb3f383a37f0fdb27fa75db46921e0e1af6' 
  AND token = 'DjXTqAYh3PvmivqouuqT+ysZwz7yB7QibOBklLwImJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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