SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aeb106b827452fbf84f256bff3699099d4c06f951ef4d12f1a8c0954524fd041' 
  AND token = 'gJJOBbkObttD1KtsSGS2xL6rmOh1XwGFMh6ZweA6mUU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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