SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '596e11ff256b01d0411b4b45b679eb2d9cbf4c6a8ec77dc66aaa1d925902cc48' 
  AND token = '45J0uiouB0fzPzsSiXJM8mKoA0n2VLpPSUvb599IlNI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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