SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b007f84e3427633539f6b4dc60818cf20072ae2f4ac3a8077be2ccf86554abd8' 
  AND token = '7c3dLzziizCZvylhFIpxF4mO+GAaqqkreQvKv6ahMt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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