SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '27e064dcc7d77b65bb957581e0e6832563a0df6bf1bb4b5856a7c12c821c489e' 
  AND token = 'J2RiEzQPFZUuvEcICOxSLmbIFCts+HuuzUq1aVSn5Q0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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