SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '10117cf65fffbc6deeb12faee5351b6df0fc88917598050f310789ba402b4d64' 
  AND token = '9OLzuhEdgY+9zxUbYUQ/YW385rY8/SAhvbgVJXvAQkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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