SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61e98c2dde1b3a2f319017382cd6283f9716f05fde57a0a26363d9eb41aae712' 
  AND token = 'GeYrFY52ih78Vn0HktccROpmTqq5V0lB5hHmBOn2ABQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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