SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b389b9083d02d5228f4e1407044dee79d734949b168a0c63cfc580ee5870180' 
  AND token = 'rBgY4edgTUYFNJV44hrfsjQDuFA7QG8ZqkjYs4ew+f4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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