SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6bce66a40327206050b76d51d9b9d82818176945a2ec3ae8dc430ebe64c43613' 
  AND token = 'yQr/sv3giPbBMDPMcYWSnPUjVMNR9p/3+dxAofvhH7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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