SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '27eb9cde53f560afab54f0d93dbb00b9b637b80a25d4941f55eeb86e3d833f41' 
  AND token = 'ITMpwkSVc6hz5QBiPPgc2oTW7OBKfh+XZxyEThOIbbQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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