SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a5386095d83f1ef5b29a3104c49f0783e8a6a9c169ee62637d525c0dde0cd2c3' 
  AND token = '/xzda0GdRXdJ7ZTpkE8btmh5p1JGy70KqpHsheOCPL0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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