SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cb068cc15964846238ade5a856c8714111e893c6c7ea093e2013bded37948243' 
  AND token = '5dXgUGkVF5s+PUHcht8VlE0WT64zC3JTNkm47VYL2u4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}