SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fba21b6124c9e23c607daf558cbb54324528f72e4cd347f51eb341a9d2587163' 
  AND token = '6XPBqtVvmobi818vKNNVbAoHMQ3k+RajXAwG7zmMDCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00053

JSON explain

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