SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce09f8992d56938153bc339f27b0c9097dfa1f18b1ed40bd2f65044e015ba6d6' 
  AND token = 'pdSFjOd3hVk4+9vLwcvhyiPf1zFDqthhVKzMYyG0t/E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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