SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82ad19dc3f9a691311f44033204b2fedfc414406c6377205412d7448c8e7f0a4' 
  AND token = 'yDHNyXuuilVQZ4E3+75+WNQjs/lLDkia582xZ0/bvoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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