SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9cc30657f32e78b2b90c7334f8aaca590b86b134275836823077840e1d5d08d4' 
  AND token = 'VYTpCQIfjbI0qB8bzvtO1iiBA8HOde3YgYOdaD9v0FE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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