SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '43c5a115fd4a574fe9a289a4eca619417f51c45e7bc1ca30ab203ab1393358cd' 
  AND token = 'XTApUIdAaSCW3owuctkDAbNBSs9revRcMZOslh/VNaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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