SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f647fc2889b786ca93100d57e565add97bd9c8bb03048a1e0117a2766671656' 
  AND token = 'Yvi/EM8qghfuOoOaUjPBqYUdMBa9oTFP/DXmCgpwmiw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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