SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7e622a609332cf89bc28564e32c9888ca02e3edaae48d63f757be082679972b' 
  AND token = 'ufO6vzimjPPk5ks/wqYkuurEtjDKfwff4uoFgJ8XlEk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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