SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '897f478d3a54f29f6bdf9df35556e79a4fa51578a0198beadb30cdc132a5e2d9' 
  AND token = 'WQcegL9QuNnmKZHnsBvQ+bGFz+awSc/otKnal0l+lJs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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