SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '42442a25414a194bb6a0cb0dcc80bdf88a2a5fd6e7c3d8993634d9c8f1eb3e86' 
  AND token = 'alCClbIFfSuu9opeRPRKmInfbohaJvqAj8jY5abrfrI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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