SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89d81c6140ea89f12cd0313b7843e53e2e82cfefefccc387602eeb1d6be43fac' 
  AND token = 'afdkmxE+fRAlBSowymqqBjDq4NLmQbOJ3/OkK0Uul1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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