SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f425c8ac5886c2d26270192e22bc3a659037382b0a65dbfb14c92477ec51dd8d' 
  AND token = 'jqSuewydaMuFzj5jPPfZyCykHbc17Bre/Z3M9wHXbK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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