SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2e6ddd1fea07f34a6cff7e8e0fbab8ba18f9f11e6e27c8b232531d72d8096b6d' 
  AND token = '8X/5/z8yLzYAw+Ph/IhZ8P+DLN5HQZizvjPK+AWms4E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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