SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5dd89d1d77268d267644a5bfa3ef8e67fd720de5cc5f97970083a5a5c00278ee' 
  AND token = 'OflOBT+HkwwV7LBvJFjOoNgnpFqGVfzFUtbWARVcGww=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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