SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5bd263f5543069f1c88e513e5f4e60b564a7868ddda0e8012b47e5e6c4150ee1' 
  AND token = '0kTvVyU0DSEiApaQRbBtYOSForshHMW2CIL4aEsv98o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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