SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc92d15872582361c003a7ce34725fd4c61ef450989b62f33712d9921b660976' 
  AND token = '2UJCWAYy5PKzlNexdjzt7gilQkv8I1yXDHYBnASnmGQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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