SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db6377e4e2e109af4ae335331c33eea8069c8297fd0113fe52c480b1e381826d' 
  AND token = '5vWZEQzD1GigrPVRH4O7JpDaxHkruVDBpjhiK/vVmOM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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