SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3e7c56ef5f04b993c3f0822a6d228a112c19c861109a81479a9433f3f65e8b6c' 
  AND token = 'c0iEmlb75iPn+B65dcuXCwxtyPdlI3K11p4lsQMg2l0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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