SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89dd9223b48c074a939d51d7406bbd4d7cf1d4dead7b3bf6263070cec447e6e6' 
  AND token = 'fVA9ktknx6qZf9LbH/LT8vtIRAJDKf8QMoUwZswYjwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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