SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8cd6e0203c65887a87f912a6eb6c9f7086d3917218b1c48d28c211a251172ddb' 
  AND token = 'GvGBxNVBojsg1UyUuk/1dB81y2j/BLYclXAyJ9lO9yo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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