SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4fdb1f057d2278b5870f71e71eb697bbebb4d1974823aed0683a2bb975952d96' 
  AND token = 'fmz0RozN8DDGLT/6MBrAzC+Fy4VvxFSZFshKj1yde0U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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