SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '08813224f2fd62a3d03a9bb01a90b12a85799b94efe3c57f58972c73f0ec3c7f' 
  AND token = 'Kf6fjtoA/n38PoQEDIxanc/cT0oFgVouR/0xpRzPOow=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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