SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9d43f9f78d96946420a49b3d682417ae7c23fb102c9f8a3f4b8a999801c10c95' 
  AND token = 'hFBC/7GIhtIAmHG/rlaJAwkfRzmdCVRBP+KUgFN9djo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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