SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b7c1ec87ede6fc13c7155a63eded9cb4e7686ed2615d0411b9b457a17ac82d1e' 
  AND token = 'XIc0r973NaRwQhk8IuyNfzlbPYMW2H8QJCj2R6QyAWU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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