SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '738708a696ca30e795b3f8511efecc0552ff15164e09d6a4c5bdc1a2c006cab2' 
  AND token = '/Isbbm38/FZKcwR5KoH9fLcH6r1SdsKI9j1mKZSi2Is=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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