SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '29131087991961df6a50dd920b5a1af8059fce346076c081bd241f167b4ef4c5' 
  AND token = 'YphVSjaM1goxc311tgqycJj1+EKZNUzol49OEIyToqw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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