SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c7bdb30cad535f50a97ef729079948a83ca1b0a99151df06d5f0bdb47501f52' 
  AND token = 'BdxDqMrDYs4BXosJnxTC/HEyS8oRQhW5NjIxx+Zi6xg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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