SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cde4563d3a84f8bf16a623cff53bf7e85741aab3d043ed237eb3666d36dade36' 
  AND token = 'IXI6IaLQVdSkz8d0A8k+uieXPSSnVSzCXFCOrBEOxb8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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