SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a18cd0276e9da8db4c198d52f8509c2f8012c2add5d35ff2d9ec803340406fa' 
  AND token = 'wfgpF0oNmvAwWhypvJUAN+v1fiORRSGd1E8z2PiB/g4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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