SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f11bcc38448929f8c8688ad63e37e6fccc7a0276c20f9eaa8948a7e4dbd5d012' 
  AND token = 't88XQHGxtfYhveLlMS79zPQOgqXKbckMlKWMPH5szZQ=' 
  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"
    }
  }
}