SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59cfcefccbfed7db364bb6925cab072e5b86ca15cf1d194a2321f4b1d40c79fd' 
  AND token = 'rAc92ZotlbPNkVal6XBuDxXFR5kyBMpc1neaX7+6EgE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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