SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dda3356b2a984f2cb7e39884931879db9f97d7da6ba0fb552712ecade0c99082' 
  AND token = '0caSepOiBhbsGDYYgZEVXwJ6JT5r1j6Ow9rKFvZVKiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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