SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9952ecacf5d788a0676cdcbff37e1c953a75043d3986542873a3265a975a7131' 
  AND token = 'd6TqlS2GZpa0gjLZJ6W6y48iiBF6OhWaFdUVmrMxK5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}