SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1b9be5b0bbc2b9c27b5fc2894d32eb5012f85eb87c50191efcee659da3b5fc7' 
  AND token = 'bodmsDZO1oLDmuMLdfmAI68d9DXcQmLdGKLsvP5Jj98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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