SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '01b7781fc3d141471ae9136018f31aea62acee1f9125f5b22bb66a065e1c79d9' 
  AND token = 'n9TQkzRKjLhDsSS2WXbPeJJUg6FO/GT5NTKvN+hZgho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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