SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96b8106bedaa4d519b0fa04e31f91e0c8af186efb811402c1ac6249c84064e15' 
  AND token = 'NK7DhAyiSQh5o/QE1dDianJt984qDcUUA0lsQFv4uBk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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