SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8b717e83812480dcb7cf1beccb25784ab31fe2f65c07ede106702478655aaa95' 
  AND token = 'kN6ZMDq6Kiw8jDbDRnOnuNIztxlplYZPYAfX5gccf8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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