SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5830f623852842f751b9c4fb2c837c04b6c3ec180a90a90bcd848cfcc314326d' 
  AND token = 'vIZv29yn0LRg+kZ64lxt0RKBJUzCPnKuLPLE+ThuE/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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