SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf611d96b27be6e098fde036ffdf176bbe5a455c189b0d18c207a8f0a15d4653' 
  AND token = 'j71L3L54OUkjflnpG8Dh1C1iOVjIHf1uk2scydu5huI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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