SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5b4bf817f276590eabcd3ccc112bf7e930d1df3cb8bf5e7176f133f5d572e801' 
  AND token = 'XYPxJjW6AmtxJXH6dBGgZ0HKZfTwsbAfU2mOLbJn6TQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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