SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb833c88a80dadccc0066995f1182f9e0afa906398ae2c49e48ac96da5116df9' 
  AND token = 'RmX8lQPKK1wwZQlS7TIL1SUawy5H/aYTbgxTjfW+pZI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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