SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '378651c61bb030e3ebce25135bb5a99fb03042ed1a74c25b88c91ea275de9a1e' 
  AND token = 'BLfM/6fo3KFtS/Y67Lwloa4wNsj/Faml4Z2aqXmWDk0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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