SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'befe301ac0c2144383581e62e62748777ac97f04646a4aa53779562e3ac9cbff' 
  AND token = '7y+w9CCVr2h0tZ9/tUJzC/0qNZGPQju3Y4JFIzJMEbM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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