SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '628986e5e7368e821e8b0c355170c9c46423107414ac6f39f3f56233f8901530' 
  AND token = 'lKbyRVZDQRkXVpDHHrYhBplUnQtR3ZdrMXvmaHE+rSk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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