SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48a2eb9def0922f65f4870cf9852deacd2b1df827f95d9a4805e8b1df040a643' 
  AND token = 'GrKataVWK1jx3h/rlsjoRXFgRVwWUjhqMcJrMI5Luic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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