SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '93b0d1373693af00a2c99678708e9c7b42ec8b366ded16133aa04824f2c905b6' 
  AND token = 'YmyDYpXKh5+hxkeOTrHczKCwrdlBDh854zzM8SbsIVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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