SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '779f8218099c705e6599a0696e6482a5f47ad4b3075972f57978578c824c0bd8' 
  AND token = '0xKKdv/6O8qSyS6QMY+Sh3JD7dXuKLGaoRV1jyqKYL4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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