SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d2e7fefae9775e4389677c6cabab033bd0562a7ad98f12c3c4ddd593386a5e0' 
  AND token = 'bi0xzRUxk3ypHfNWLK9ck8Gz21nA/yyAC0c7RL7cKNQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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