SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5ac9efc23be90390912070c2ccb194974a7e8ebdf090b54b2791a16e6890161b' 
  AND token = '7XOHLGv4q34PIJZlJqMBgiIfXOPul5hLT/r5kLFgUuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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