SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'e5c83a4d0f78b6db81c6a4df86d37a51213cc1a3666cb046d1fa632c83c95f0d' 
  AND token = 'OVusgX+OIPzCCeUFAtb0K93Yb2bfl25MTE2hU12TgAM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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