SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96756e4c1dacba3cdc16fe5240e44ca6e2d8613af8faa638ec2c48f956c0e551' 
  AND token = 'o5igwSDc7jdDHW0mw/CzvRj64okY/ZDp3KJwo5SI338=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00082

JSON explain

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