SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bed177ea45b8f5af26a4a02177048614537e14f7c50303010ea1ff871f5d41be' 
  AND token = 'kefNvQCXUKg2zUNkNCqqKfKy1uINMl684sQfW/Ene9U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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