SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f12c6576210958fd45750fcbd3213d38cf527725228a805c3f477a7ec71b29d6' 
  AND token = 'IWd0CEbQuGNNCgvY/OaDgzVhmemJsaOOSX9DUrxFRAE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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