SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5d45193d20ab2ddaa3645298ca7262e0c37f623150fc1dc5c552c28420436822' 
  AND token = 'W7LfIg6+E/AW0NMRUXgfbkAnSV1rcaG0A3bKnnlzM9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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