SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5044468fef8aef1c533823a88db9ebf3793f971bbc97c6bdcab1196a170d8be1' 
  AND token = 'IXrbaUCT2qpI0qvAzwEhNe62FmplsaN2hTpD9UNvnlY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}