SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c0bece91a74faf8f82a7881a6b105a224b9eaac9c1bcf18865b7d649993baadc' 
  AND token = 't0H9aU6yO3TZRvntZeRwRmCtrDivgFVFXUQpAoybHrU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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