SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b26a68dd083df78c437764fb76584d8c81e1bd86a0637988052444ea5f2fb95' 
  AND token = 'bdja0BFwbxLaSm2KhXlfONbMQ/6PIhKUpK+KRZY3NGM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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