SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96ae5133a7eeb4fd1e65af8ded34e1dff7573c919cf2642af835ea947b4966c9' 
  AND token = 'E/3jBxCBlipLMZdghNkHHa5NSuVVd0BByyJ+oyxNTrA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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