SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '176169f657c1681795b2516685e6671ddd72e939329ea5c2264708e2a4aa62d1' 
  AND token = 'ZtKE2OgtZR0QjNNkXVf3erWIxe9rnoZFVo4lXwigBy0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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