SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06cd5bd9fe4d207807429767fe18d6d8237d75f6e1e4abadb3d78ae448575afa' 
  AND token = 'z0ZJM3h5a/zvLWXnps1MrSxvGRKuJKn/x7ephJLlgik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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