SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '993f2d6903bc2c9525ab283d7ac11d47bb5969e34c4d04cc7cfa3c67398ebf52' 
  AND token = 'QUAi7GySikvFbnVkazRcJHYUtMeIYl5uIDR9lTBs+XE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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