SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b80ee1787f266fe6277ee8397737736c59e7f16b59418114f4ea6c5aa3205e2' 
  AND token = 'gCsGvRB9GCGCGY2/ObwpM95rnFuvCc3vWKTVnNqzUuE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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