SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5419d5253636376affa26e57912f70dcd08a1df89787364b57b8ef73ab31e462' 
  AND token = 'jDJyCAB6SbzXeVJImXrz3ZsJplSf59KK3zvDntLD/LE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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