SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '086a345e60bf82684a729b244bebe39a0659671c3a88644a577b627902c64298' 
  AND token = 'IHvZDpOxavNPTVYVpeeme0KWtBZUXTHH10rnSNTKqos=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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