SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f82f47ba5fe094af352b4a9ad5964fe9856eb820799c59db7716309dd044d334' 
  AND token = '+G94NJuzXPPLFzT+PrGqoiuX6lUUmZC2CyZVIYSI80Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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