SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1787094e6e9680855243d4e7a8be258be2549dc03c3502916c60d5d875db596' 
  AND token = 'AoSz+VAWOeqFKVgccyUrW8LoYuM290E8OdLKSJEZS6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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