SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c14066326cbbe24a27cd8d7c28500cee94a85109a3d9e4a0c093217b4a286266' 
  AND token = 'ejZ4LSco5SdtGskgcx2NHLFKkrqYVvXeEteoTn5m8UI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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