SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8290d2a71e943563c1556ca142d55554389e393c912a49a40000ad5eaeb3f46c' 
  AND token = 'dJ4h7DEDzPfKzPkYGkkly8UidLiJMU0N7GjtMjFwAtc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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