SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5926cf4fd9ca0593dd3ece676ce8d9ed04db2f6ea99bc46024adb55280462458' 
  AND token = 'XG0qyz4d+elbalkGGrN7LlbChRmCiAhvjpgaW5iw5k0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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