SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0b9690b3dd4cfb2085b478d4509f38e68d6aacf05a06801be9ef4cd431523b3a' 
  AND token = 'PWlmXns2aVWh3BgbWzcefzaWfynsX6QvBHJrRjcKGtY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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