SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e7d9408fcb8acd8825eff7facbb79223936cc2ba48ab58a611c086dcbc9822d' 
  AND token = 'Pioq5Nr+n4Y66VxTrtSmqanJ8LBmmWWaN/Y9rZxCveo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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