SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '03de22ee81c0d943c8b876d81c950a20faf06aa86a9567957893768f306ddef1' 
  AND token = 'HWE1eji4mffX+Gdag7ZWxk3vKgIdMhMTPxKpuuknyeQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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