SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e14ede2effb7ad0bc7e73e9b07e88b7fc4d21f7761640e329ab1b0d6bd170b98' 
  AND token = 'fINDJVu/azobaZCUtS9tArWbSVYUkPdrvksQbuFdbfU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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