SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eec45e15aa9215db3c9da2f19bdb819d8ef2902fc19fbd5bb062a92aa60a4a83' 
  AND token = 'BCAXYJHTAqvtoeWQ1IaRGIbj2bHR2kx/MODLxCwFOYA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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