SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '19c623b7ef65979aeb479afe37e241d71eb09a314ac095c7d31c0782dd9488d6' 
  AND token = '0SrUpLcvmBwP7oZ9E0K5og33t1s8G3A1XgVM//MFI9E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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