SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62e9d835dde1cc1dbbc499c5fa7517bdaba97afa0fa9d83d32ed55c655d62223' 
  AND token = '7oYMkMho1fBksArhQV/EkcCHTp7hmGXRgo4phFUq1xw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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