SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '13dca2b5d918f568663577e5251e5e2e728761e8b30e9a4ab71024e32791ea75' 
  AND token = '0tSsf0BG5QMKMw18xPivfXD72OtKTQDch2I6gcg+uMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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