SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac62e2c73fa7aaef2f5ce8bf78ea8d2344adbf9ef2ef542c5ad32d30cb9964f6' 
  AND token = 'NvK5kc+kAcvBhxGvQpSP9Ua/Bf4QDmHCEfHMmH4fMW4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}