Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b7b2c577b2b6b2a629e3381c7ba6ac829768ea9c536f615c206024d479deff1f' 
  AND token = 'r4aciqs1ZoIzf4TA/fYWLYWrwDKaEWnSbqLxhmk0ovw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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